Replace compatibility mode texture formats (#1518)

Co-authored-by: Alexdoru <[email protected]>

.gitignore

@@ -36,3 +36,4 @@ addon.local.gradle
 addon.local.gradle.kts
 addon.late.local.gradle
 addon.late.local.gradle.kts
+local/

README.MD

@@ -12,6 +12,14 @@
    * Complementary + Euphoria Patches is the primary compatibility target
    * Sildurs, Seus, and any other shaders might work
 
+## Core Profile
+Targets GL 3.3+ core profile
+* FFP emulation via generated GLSL shaders
+* Display list emulation
+* Software matrix stacks and state management through GLSM
+* GL_QUADS → GL_TRIANGLES conversion
+* Automatic transformation of mod shaders that use compat-only GLSL builtins (`gl_ModelViewMatrix`, `texture2D`, etc.)
+
 
 # Required Dependencies
 * [UniMixins](https://github.com/LegacyModdingMC/UniMixins/releases) >= 0.1.23
@@ -56,9 +64,9 @@
   * The [Iris](https://github.com/IrisShaders/Iris) Team: coderbot, IMS212, Justsnoopy30, FoundationGames
   * Asek3 for the Iris Forge port [Oculus](https://github.com/Asek3/Oculus/tree/839ce8eca8cf0c4f6b7a1322b906e5c99125ca69)
   * Backported code under the LGPL
-* Sodium
+* Sodium / Celeritas
   * JellySquid & the CaffeineMC team, for making Sodium in the first place
-  * Embeddedt for [Embeddium](https://github.com/embeddedt/embeddium/tree/dc59ca357c25beefd6288f0d1d40b4cd8e670ab8) under the [LGPL 3.0](https://github.com/embeddedt/embeddium/blob/16.x/forge/LICENSE)
+  * Embeddedt for Celeritas used under the LGPL 3.0
 * Reese's Sodium Options
   * FlashyReese for [Reese's Sodium Options](https://github.com/FlashyReese/reeses-sodium-options/tree/aa4ea67047cf53e54976e93c6bb1ab5ba16b142b) under the [MIT license](https://github.com/FlashyReese/reeses-sodium-options/blob/aa4ea67047cf53e54976e93c6bb1ab5ba16b142b/LICENSE.txt)
 * Neodymium
@@ -85,3 +93,8 @@
   * FalsePattern for [FalseTweaks](https://github.com/falsepattern/falsetweaks) - Item Rendering Optimizations taken from FalseTweaks under the LGPL 3.0 license
 * Beddium
   * Venn and Falsepattern for [Beddium](https://github.com/vfx-dev/Beddium) - MinimapRenderer, SafeChunkTracker, and some debug commands adapted under the LGPL 3.0 License
+* [Mesa](https://gitlab.freedesktop.org/mesa/mesa) — Code ported and/or inspired from Mesa - under the MIT licensed
+  * Display list ID allocator ported from [util_idalloc](https://gitlab.freedesktop.org/mesa/mesa/-/blob/main/src/util/u_idalloc.c) (Copyright 2017 Valve Corporation)
+  * FFP vertex shader generation inspired by ffvertex_prog.c (Copyright 2007 VMware, Inc.)
+  * FFP fragment shader generation inspired by ff_fragment_shader.c (Copyright 2007, 2009 VMware, Inc. / 2010-2011 Intel Corporation)
+  * Fog parameter optimization inspired by st_nir_lower_fog.c (Copyright 2023 Google LLC) and prog_statevars.c (Copyright 1999-2007 Brian Paul)

build.gradle.kts

@@ -1,3 +1,5 @@
+import xyz.wagyourtail.jvmdg.gradle.task.files.DowngradeFiles
+
 plugins {
     id("com.gtnewhorizons.gtnhconvention")
 }
@@ -5,6 +7,7 @@ plugins {
 minecraft {
     extraRunJvmArguments.add("-Dangelica.enableTestBlocks=true")
     extraRunJvmArguments.add("-Dangelica.dumpClass=true")
+//    extraRunJvmArguments.add("-Dorg.lwjgl.util.Debug=true")
 //    extraRunJvmArguments.addAll("-Dlegacy.debugClassLoadingSave=true")
 //    extraRunJvmArguments.addAll("-Drfb.dumpLoadedClasses=true", "-Drfb.dumpLoadedClassesPerTransformer=true")
     //extraRunJvmArguments.add("-Dangelica.redirectorLogspam=true")
@@ -45,6 +48,18 @@ tasks.register<Copy>("copyDependencies") {
 
 val embedOnly: Configuration by configurations
 
+// Downgrade embedOnly jars for the tests
+val downgradeEmbedOnlyForTest by tasks.registering(DowngradeFiles::class) {
+    inputCollection = embedOnly
+}
+
+tasks.test {
+    dependsOn(downgradeEmbedOnlyForTest)
+    classpath = classpath
+        .minus(embedOnly)
+        .plus(files(downgradeEmbedOnlyForTest.map { it.outputCollection }))
+}
+
 tasks.shadowJar {
     from(embedOnly.map(::zipTree))
     relocate("com.mitchej123", "com.mitchej123")

dependencies.gradle

@@ -53,6 +53,7 @@ configurations {
     embedOnly.canBeResolved = true
     compileClasspath.extendsFrom(embedOnly)
     testCompileClasspath.extendsFrom(embedOnly)
+    testRuntimeClasspath.extendsFrom(embedOnly)
 }
 
 
@@ -71,17 +72,18 @@ dependencies {
 
     // Iris Shaders
     compileOnly('org.jetbrains:annotations:26.0.2')
-    api("com.github.GTNewHorizons:GTNHLib:0.9.0:dev")
+    api("com.github.GTNewHorizons:GTNHLib:0.9.36:dev")
+
     shadowImplementation("org.anarres:jcpp:1.4.14") // Apache 2.0
-    shadowImplementation("org.taumc:glsl-transformation-lib:0.2.0-25.g3a943bb") {
+    shadowImplementation("org.taumc:glsl-transformation-lib:0.2.0-26.g5ee7d96-GTNH") {
         exclude module: "antlr4" // we only want to shadow the runtime module
     }
     shadowImplementation("org.antlr:antlr4-runtime:4.13.2")
     compileOnly "org.apache.ant:ant:1.8.2"
 
     // Celeritas (transitive=false: deps provided by GTNHLib/runtime)
-    embedOnly("org.embeddedt.celeritas:celeritas-common:2.5.1-GTNH") { transitive = false }
-    embedOnly("org.embeddedt.celeritas:celeritas-lwjgl2-service:2.5.1-GTNH") { transitive = false }
+    embedOnly("org.embeddedt.celeritas:celeritas-common:2.5.3-GTNH") { transitive = false }
+    embedOnly("org.embeddedt.celeritas:celeritas-lwjgl2-service:2.5.3-GTNH") { transitive = false }
 
     // Because who doesn't want NEI
     devOnlyNonPublishable('com.github.GTNewHorizons:NotEnoughItems:2.8.35-GTNH:dev')
@@ -107,24 +109,23 @@ dependencies {
 
     compileOnly("curse.maven:minefactory-reloaded-66672:2277486")
 
-    compileOnly("com.github.GTNewHorizons:NotEnoughIds:2.1.10:dev") // Mixin Version
-    compileOnly("com.github.GTNewHorizons:NotEnoughIds-Legacy:1.4.7:dev") // ASM Version
+    compileOnly("com.github.GTNewHorizons:NotEnoughIds:2.1.10:dev")
 
-    compileOnly(rfg.deobf("curse.maven:ntm-space-1121235:6974420"))
+    compileOnly(rfg.deobf("maven.modrinth:ntmspace:X5593_H261"))
 
     compileOnly(rfg.deobf("curse.maven:campfirebackport-387444:4611675"))
     compileOnly(rfg.deobf("curse.maven:xaeros-minimap-263420:5060684"))
     compileOnly(rfg.deobf("curse.maven:security-craft-64760:2818228"))
+    compileOnly(rfg.deobf("curse.maven:et-futurum-requiem-441392:5873837"))
 
-//    runtimeOnlyNonPublishable("com.github.GTNewHorizons:CoreTweaks:0.3.3.6-GTNH")
-    // For testing alternative splash screens, can be sourced from https://github.com/MalTeeez/ModernSplash/releases
-    //runtimeOnly(rfg.deobf(files("dependencies/modernsplash-1.7.10-1.2.2-dev.jar")))
+    // For testing alternative splash screens — https://github.com/MalTeeez/ModernSplash/releases
+    // devOnlyNonPublishable("com.github.MalTeeez:modernsplash:1.7.10-1.2.4:dev")
 
     // Hodgepodge
     transformedMod("net.industrial-craft:industrialcraft-2:2.2.828-experimental:dev")
 
     // Better Crashes
-    compileOnly("com.github.GTNewHorizons:BetterCrashes:1.4.0-GTNH:dev")
+    compileOnly("com.github.GTNewHorizons:BetterCrashes:1.4.1-GTNH:dev")
 
     afterEvaluate {
         dependencies {

gradle/gradle-daemon-jvm.properties

@@ -1,12 +1,12 @@
 #This file is generated by updateDaemonJvm
 toolchainUrl.FREE_BSD.AARCH64=https\://api.foojay.io/disco/v3.0/ids/c5ee947fbfb70bc347d8d531e3a578c4/redirect
-toolchainUrl.FREE_BSD.X86_64=https\://api.foojay.io/disco/v3.0/ids/5ee463876563a46fff651cce1bc53a4c/redirect
+toolchainUrl.FREE_BSD.X86_64=https\://api.foojay.io/disco/v3.0/ids/cd495626d2ee49a75447e3fdc6afb287/redirect
 toolchainUrl.LINUX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/c5ee947fbfb70bc347d8d531e3a578c4/redirect
-toolchainUrl.LINUX.X86_64=https\://api.foojay.io/disco/v3.0/ids/5ee463876563a46fff651cce1bc53a4c/redirect
+toolchainUrl.LINUX.X86_64=https\://api.foojay.io/disco/v3.0/ids/cd495626d2ee49a75447e3fdc6afb287/redirect
 toolchainUrl.MAC_OS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/e1118b4c7c2858d28154d086dbff010e/redirect
 toolchainUrl.MAC_OS.X86_64=https\://api.foojay.io/disco/v3.0/ids/59a9771cad43219260d9aac9a8ec4d6a/redirect
 toolchainUrl.UNIX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/c5ee947fbfb70bc347d8d531e3a578c4/redirect
-toolchainUrl.UNIX.X86_64=https\://api.foojay.io/disco/v3.0/ids/5ee463876563a46fff651cce1bc53a4c/redirect
-toolchainUrl.WINDOWS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/832229f0f6f0be60ed817c5a5e5848eb/redirect
-toolchainUrl.WINDOWS.X86_64=https\://api.foojay.io/disco/v3.0/ids/b96cb7670c095245220e7d01d5927b58/redirect
+toolchainUrl.UNIX.X86_64=https\://api.foojay.io/disco/v3.0/ids/cd495626d2ee49a75447e3fdc6afb287/redirect
+toolchainUrl.WINDOWS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/a4c09dd2e2d7079373d30e524bbc2829/redirect
+toolchainUrl.WINDOWS.X86_64=https\://api.foojay.io/disco/v3.0/ids/8e1d9ee5d0f13e442218f6884a306da1/redirect
 toolchainVersion=25

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

gradlew

@@ -57,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/b631911858264c0b6e4d6603d677ff5218766cee/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.

repositories.gradle

@@ -22,5 +22,18 @@ repositories {
             includeGroup 'org.taumc'
         }
     }
+    ivy {
+        name = 'modernsplash-github'
+        url = 'https://github.com/MalTeeez/ModernSplash/releases/download/'
+        patternLayout {
+            artifact '[revision]/[module]-[revision](-[classifier]).[ext]'
+        }
+        content {
+            includeModule 'com.github.MalTeeez', 'modernsplash'
+        }
+        metadataSources {
+            artifact()
+        }
+    }
     mavenLocal()
 }

settings.gradle.kts

@@ -16,5 +16,5 @@ pluginManagement {
 }
 
 plugins {
-    id("com.gtnewhorizons.gtnhsettingsconvention") version("2.0.13")
+    id("com.gtnewhorizons.gtnhsettingsconvention") version("2.0.23")
 }

src/main/java/com/gtnewhorizons/angelica/AngelicaMod.java

@@ -1,19 +1,21 @@
 package com.gtnewhorizons.angelica;
 
-import static com.gtnewhorizons.angelica.AngelicaMod.MOD_ID;
-
 import com.gtnewhorizons.angelica.common.BlockError;
 import com.gtnewhorizons.angelica.compat.ModStatus;
+import com.gtnewhorizons.angelica.config.ConfigMigrator;
 import com.gtnewhorizons.angelica.proxy.CommonProxy;
 import com.gtnewhorizons.angelica.utils.AnimationMode;
 import com.gtnewhorizons.angelica.utils.ManagedEnum;
 import cpw.mods.fml.common.Mod;
 import cpw.mods.fml.common.SidedProxy;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import cpw.mods.fml.common.event.FMLInitializationEvent;
 import cpw.mods.fml.common.event.FMLPostInitializationEvent;
 import cpw.mods.fml.common.event.FMLPreInitializationEvent;
+import me.jellysquid.mods.sodium.client.gui.SodiumGameOptions;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import static com.gtnewhorizons.angelica.AngelicaMod.MOD_ID;
 
 @Mod(
         modid = MOD_ID,
@@ -33,6 +35,15 @@ public class AngelicaMod {
     public static final String MOD_ID = "angelica";
     public static final Logger LOGGER = LogManager.getLogger("Angelica");
 
+    private static SodiumGameOptions CONFIG;
+
+    public static SodiumGameOptions options() {
+        if (CONFIG == null) {
+            CONFIG = SodiumGameOptions.load(ConfigMigrator.handleConfigMigration("angelica-options.json"));
+        }
+        return CONFIG;
+    }
+
     @SidedProxy(clientSide = "com.gtnewhorizons.angelica.proxy.ClientProxy", serverSide = "com.gtnewhorizons.angelica.proxy.CommonProxy")
     public static CommonProxy proxy;
 

src/main/java/com/gtnewhorizons/angelica/client/font/BatchingFontRenderer.java

@@ -1,30 +1,35 @@
 package com.gtnewhorizons.angelica.client.font;
 
 import com.google.common.collect.ImmutableSet;
+import com.gtnewhorizon.gtnhlib.bytebuf.MemoryStack;
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.IndexBuffer;
 import com.gtnewhorizon.gtnhlib.util.font.GlyphReplacements;
 import com.gtnewhorizons.angelica.config.FontConfig;
 import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.streaming.StreamingUploader;
 import com.gtnewhorizons.angelica.mixins.interfaces.FontRendererAccessor;
-import cpw.mods.fml.client.SplashProgress;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+import lombok.Setter;
 import net.coderbot.iris.gl.program.Program;
 import net.coderbot.iris.gl.program.ProgramBuilder;
 import net.minecraft.client.gui.FontRenderer;
 import net.minecraft.util.MathHelper;
 import net.minecraft.util.ResourceLocation;
-import org.apache.commons.io.IOUtils;
+import org.embeddedt.embeddium.impl.render.shader.ShaderLoader;
+import org.joml.Matrix4f;
 import org.lwjgl.opengl.GL11;
-import org.lwjgl.opengl.GL13;
+import org.lwjgl.opengl.GL15;
 import org.lwjgl.opengl.GL20;
+import org.lwjgl.opengl.GL30;
+
 
-import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
-import java.nio.IntBuffer;
-import java.nio.charset.StandardCharsets;
+
 import java.util.Comparator;
 import java.util.Objects;
 
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryStack.stackPush;
 import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.*;
 
 /**
@@ -37,50 +42,43 @@ public class BatchingFontRenderer {
     /** The underlying FontRenderer object that's being accelerated */
     protected FontRenderer underlying;
     /** Array of width of all the characters in default.png */
-    protected int[] charWidth = new int[256];
-    /** Array of the start/end column (in upper/lower nibble) for every glyph in the /font directory. */
-    protected byte[] glyphWidth;
+    protected int[] charWidth;
     /**
      * Array of RGB triplets defining the 16 standard chat colors followed by 16 darker version of the same colors for
      * drop shadows.
      */
-    private int[] colorCode;
+    private final int[] colorCode;
     /** Location of the primary font atlas to bind. */
     protected final ResourceLocation locationFontTexture;
 
     private final int AAMode;
     private final int AAStrength;
-    private final int texBoundAttrLocation;
+    private final int mvpMatrixLocation;
     private final int fontShaderId;
 
     final boolean isSGA;
     final boolean isSplash;
 
+    /** For use with modded books. Affects calculations and forces some defaults. */
+    @Setter
+    boolean bookMode = false;
+
     private static class FontAAShader {
 
         private static Program fontShader = null;
         public static Program getProgram() {
             if (fontShader == null) {
-                String vsh, fsh;
-                try {
-                    fsh = new String(IOUtils.toByteArray(Objects.requireNonNull(FontAAShader.class.getResourceAsStream("/assets/angelica/shaders/fontFilter.fsh"))), StandardCharsets.UTF_8);
-                    vsh = new String(IOUtils.toByteArray(Objects.requireNonNull(FontAAShader.class.getResourceAsStream("/assets/angelica/shaders/fontFilter.vsh"))), StandardCharsets.UTF_8);
-                } catch (IOException e) {
-                    throw new RuntimeException(e);
-                }
-
-                ProgramBuilder builder = ProgramBuilder.begin("fontFilter", vsh, null, fsh, ImmutableSet.of(0));
-                fontShader = builder.build();
+                final String vsh = ShaderLoader.getShaderSource("angelica:fontFilter.vsh");
+                final String fsh = ShaderLoader.getShaderSource("angelica:fontFilter.fsh");
+                fontShader = ProgramBuilder.begin("fontFilter", vsh, null, fsh, ImmutableSet.of(0)).build();
             }
             return fontShader;
         }
     }
 
-    public BatchingFontRenderer(FontRenderer underlying, int[] charWidth, byte[] glyphWidth,
-                                int[] colorCode, ResourceLocation locationFontTexture) {
+    public BatchingFontRenderer(FontRenderer underlying, int[] charWidth, int[] colorCode, ResourceLocation locationFontTexture) {
         this.underlying = underlying;
         this.charWidth = charWidth;
-        this.glyphWidth = glyphWidth;
         this.colorCode = colorCode;
         this.locationFontTexture = locationFontTexture;
 
@@ -93,96 +91,138 @@ public class BatchingFontRenderer {
 
         FontProviderMC.get(this.isSGA).charWidth = this.charWidth;
         FontProviderMC.get(this.isSGA).locationFontTexture = this.locationFontTexture;
-        FontProviderUnicode.get().glyphWidth = this.glyphWidth;
 
         //noinspection deprecation
         fontShaderId = FontAAShader.getProgram().getProgramId();
         AAMode = GL20.glGetUniformLocation(fontShaderId, "aaMode");
         AAStrength = GL20.glGetUniformLocation(fontShaderId, "strength");
-        texBoundAttrLocation = GL20.glGetAttribLocation(fontShaderId, "texBounds");
+        mvpMatrixLocation = GL20.glGetUniformLocation(fontShaderId, "u_MVPMatrix");
+        if (ebo == null) {
+            ebo = new IndexBuffer();
+            vbo = GL15.glGenBuffers();
+            allocateBuffers();
+        }
     }
 
     // === Batched rendering
 
-    private int batchDepth = 0;
-
-    private int vtxWriterIndex = 0;
-    private int idxWriterIndex = 0;
-    private static final int INITIAL_BATCH_SIZE = 256;
+    private static final int INITIAL_BATCH_SIZE = 2048;
     private static final ResourceLocation DUMMY_RESOURCE_LOCATION = new ResourceLocation("angelica$dummy",
         "this is invalid!");
-    private FloatBuffer batchVtxPositions = memAllocFloat(INITIAL_BATCH_SIZE * 2);
-    private ByteBuffer batchVtxColors = memAlloc(INITIAL_BATCH_SIZE * 4);
-    private FloatBuffer batchVtxTexCoords = memAllocFloat(INITIAL_BATCH_SIZE * 2);
-    private IntBuffer batchIndices = memAllocInt(INITIAL_BATCH_SIZE / 2 * 3);
-    private FloatBuffer batchVtxTexBounds = memAllocFloat(INITIAL_BATCH_SIZE * 4);
+
+    // Layout in data:
+    // [v, v, t, t, c, c, c, c, tb, tb, tb, tb]
+    // v, t and tb are floats, c is bytes; 36 bytes total
+    private static final int VERTEX_SIZE = 36;
+    private static int rawCapacity = INITIAL_BATCH_SIZE * VERTEX_SIZE;
+    private static ByteBuffer vertexData = memAlloc(rawCapacity);
+    private static long vertexDataAddress = memAddress0(vertexData);
+    private static int vboCapacity;
+
+
+    // OpenGL objects (static, can be used between multiple BatchingFontRenderer)
+    private static int fontVAO = 0;
+    private static int vbo;
+    private static IndexBuffer ebo;
+
+    private int batchDepth = 0;
+
+    private int vertexDataPos = 0;
+    private int idxWriterIndex = 0;
+
     private final ObjectArrayList<FontDrawCmd> batchCommands = ObjectArrayList.wrap(new FontDrawCmd[64], 0);
     private final ObjectArrayList<FontDrawCmd> batchCommandPool = ObjectArrayList.wrap(new FontDrawCmd[64], 0);
 
     private int blendSrcRGB = GL11.GL_SRC_ALPHA;
     private int blendDstRGB = GL11.GL_ONE_MINUS_SRC_ALPHA;
 
-    /**  */
-    private void pushVtx(float x, float y, int rgba, float u, float v, float uMin, float uMax, float vMin, float vMax) {
-        final int oldCap = batchVtxPositions.capacity() / 2;
-        if (vtxWriterIndex >= oldCap) {
-            final int newCap = oldCap * 2;
-            batchVtxPositions = memRealloc(batchVtxPositions, newCap * 2);
-            batchVtxColors = memRealloc(batchVtxColors, newCap * 4);
-            batchVtxTexCoords = memRealloc(batchVtxTexCoords, newCap * 2);
-            batchVtxTexBounds = memRealloc(batchVtxTexBounds, newCap * 4);
-            final int oldIdxCap = batchIndices.capacity();
-            final int newIdxCap = oldIdxCap * 2;
-            batchIndices = memRealloc(batchIndices, newIdxCap);
+
+    private void allocateBuffers() {
+        populateEBO(rawCapacity / VERTEX_SIZE);
+    }
+
+    private void populateEBO(int capacity) {
+        final int quadCount = capacity * 6;
+        final ByteBuffer data = memAlloc(quadCount * 6 * 2);
+        long ptr = memAddress0(data);
+        for (int i = 0; i < quadCount; i++) {
+            int base = (i * 4);
+
+            // triangle 1
+            memPutShort(ptr, (short) base);
+            memPutShort(ptr + 2, (short) (base + 1));
+            memPutShort(ptr + 4, (short) (base + 2));
+
+            // triangle 2
+            memPutShort(ptr + 6, (short) (base + 2));
+            memPutShort(ptr + 8, (short) (base + 1));
+            memPutShort(ptr + 10, (short) (base + 3));
+            ptr += 12;
         }
-        final int idx = vtxWriterIndex;
-        final int idx2 = idx * 2;
-        final int idx4 = idx * 4;
-        batchVtxPositions.put(idx2, x);
-        batchVtxPositions.put(idx2 + 1, y);
+
+        ebo.upload(data);
+
+        memFree(data);
+
+    }
+
+    private void ensureCapacity() {
+        if (vertexDataPos + (4 * VERTEX_SIZE) > rawCapacity) {
+            rawCapacity *= 2;
+            vertexData = memRealloc(vertexData, rawCapacity);
+            vertexDataAddress = memAddress0(vertexData);
+
+            allocateBuffers();
+        }
+    }
+
+    private void pushVtx(float x, float y, int rgba, float u, float v, float uMin, float uMax, float vMin, float vMax) {
+        final long ptr = vertexDataAddress + vertexDataPos;
+
+        // v, v
+        memPutFloat(ptr, x);
+        memPutFloat(ptr + 4, y);
+
+        // t, t
+        memPutFloat(ptr + 8, u);
+        memPutFloat(ptr + 12, v);
+
+        // c, c, c, c
         // 0xAARRGGBB
-        batchVtxColors.put(idx4, (byte) ((rgba >> 16) & 0xFF));
-        batchVtxColors.put(idx4 + 1, (byte) ((rgba >> 8) & 0xFF));
-        batchVtxColors.put(idx4 + 2, (byte) (rgba & 0xFF));
-        batchVtxColors.put(idx4 + 3, (byte) ((rgba >> 24) & 0xFF));
-        batchVtxTexCoords.put(idx2, u);
-        batchVtxTexCoords.put(idx2 + 1, v);
-        batchVtxTexBounds.put(idx4, uMin);
-        batchVtxTexBounds.put(idx4 + 1, uMax);
-        batchVtxTexBounds.put(idx4 + 2, vMin);
-        batchVtxTexBounds.put(idx4 + 3, vMax);
-        vtxWriterIndex++;
+        memPutByte(ptr + 16, (byte) ((rgba >> 16) & 0xFF));
+        memPutByte(ptr + 17, (byte) ((rgba >> 8) & 0xFF));
+        memPutByte(ptr + 18, (byte) (rgba & 0xFF));
+        memPutByte(ptr + 19, (byte) ((rgba >> 24) & 0xFF));
+
+        // tb, tb, tb, tb
+        memPutFloat(ptr + 20, uMin);
+        memPutFloat(ptr + 24, uMax);
+        memPutFloat(ptr + 28, vMin);
+        memPutFloat(ptr + 32, vMax);
+
+        vertexDataPos += VERTEX_SIZE;
     }
 
     private void pushUntexRect(float x, float y, float w, float h, int rgba) {
-        final int vtxId = vtxWriterIndex;
+        ensureCapacity();
         pushVtx(x, y, rgba, 0, 0, 0, 0, 0, 0);
         pushVtx(x, y + h, rgba, 0, 0, 0, 0, 0, 0);
         pushVtx(x + w, y, rgba, 0, 0, 0, 0, 0, 0);
         pushVtx(x + w, y + h, rgba, 0, 0, 0, 0, 0, 0);
-        pushQuadIdx(vtxId);
+        pushQuadIdx();
     }
 
     private void pushTexRect(float x, float y, float w, float h, float itOff, int rgba, float uStart, float vStart, float uSz, float vSz) {
-        final int vtxId = vtxWriterIndex;
+        ensureCapacity();
         pushVtx(x + itOff, y, rgba, uStart, vStart, uStart, uStart + uSz, vStart, vStart + vSz);
         pushVtx(x - itOff, y + h, rgba, uStart, vStart + vSz, uStart, uStart + uSz, vStart, vStart + vSz);
         pushVtx(x + itOff + w, y, rgba, uStart + uSz, vStart, uStart, uStart + uSz, vStart, vStart + vSz);
         pushVtx(x - itOff + w, y + h, rgba, uStart + uSz, vStart + vSz, uStart, uStart + uSz, vStart, vStart + vSz);
-        pushQuadIdx(vtxId);
+        pushQuadIdx();
     }
 
-    private int pushQuadIdx(int startV) {
-        final int idx = idxWriterIndex;
-        batchIndices.put(idx, startV);
-        batchIndices.put(idx + 1, startV + 1);
-        batchIndices.put(idx + 2, startV + 2);
-        //
-        batchIndices.put(idx + 3, startV + 2);
-        batchIndices.put(idx + 4, startV + 1);
-        batchIndices.put(idx + 5, startV + 3);
+    private void pushQuadIdx() {
         idxWriterIndex += 6;
-        return idx;
     }
 
     private void pushDrawCmd(int startIdx, int idxCount, ResourceLocation texture, boolean isUnicode) {
@@ -257,9 +297,6 @@ public class BatchingFontRenderer {
      * allow for easier optimizing of blocks of font rendering code.
      */
     public void beginBatch() {
-        if (batchDepth == Integer.MAX_VALUE) {
-            throw new StackOverflowError("More than Integer.MAX_VALUE nested font rendering batch operations");
-        }
         batchDepth++;
     }
 
@@ -275,10 +312,21 @@ public class BatchingFontRenderer {
         }
     }
 
-    int lastActiveProgram;
-    int fontAAModeLast = -1;
-    int fontAAStrengthLast = -1;
+    private static final Matrix4f scratchMvp = new Matrix4f();
+    private int fontAAModeLast = -1;
+    private int fontAAStrengthLast = -1;
+
     private void flushBatch() {
+        if (vertexDataPos == 0) {
+            clearBatch();
+            return;
+        }
+
+        // Upload first (to reduce stalls)
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbo);
+        vertexData.limit(vertexDataPos);
+        vboCapacity = StreamingUploader.upload(vertexData, vboCapacity);
+
         final int prevProgram = GLStateManager.glGetInteger(GL20.GL_CURRENT_PROGRAM);
 
         // Sort&Draw
@@ -295,33 +343,48 @@ public class BatchingFontRenderer {
         GLStateManager.tryBlendFuncSeparate(blendSrcRGB, blendDstRGB, GL11.GL_ONE, GL11.GL_ZERO);
         GLStateManager.glShadeModel(GL11.GL_FLAT);
 
-        final boolean canUseAA = FontConfig.fontAAMode != 0 && prevProgram == 0;
-        if (canUseAA) {
-            GL20.glVertexAttribPointer(texBoundAttrLocation, 4, false, 0, batchVtxTexBounds);
-            GL20.glEnableVertexAttribArray(texBoundAttrLocation);
-            lastActiveProgram = prevProgram;
-            GLStateManager.glUseProgram(fontShaderId);
-            if (FontConfig.fontAAMode != fontAAModeLast) {
-                fontAAModeLast = FontConfig.fontAAMode;
-                GL20.glUniform1i(AAMode, FontConfig.fontAAMode);
-            }
-            if (FontConfig.fontAAStrength != fontAAStrengthLast) {
-                fontAAStrengthLast = FontConfig.fontAAStrength;
-                GL20.glUniform1f(AAStrength, FontConfig.fontAAStrength / 120.f);
-            }
+        GLStateManager.glUseProgram(fontShaderId);
+        if (FontConfig.fontAAMode != fontAAModeLast) {
+            fontAAModeLast = FontConfig.fontAAMode;
+            GL20.glUniform1i(AAMode, FontConfig.fontAAMode);
+        }
+        if (FontConfig.fontAAStrength != fontAAStrengthLast) {
+            fontAAStrengthLast = FontConfig.fontAAStrength;
+            GL20.glUniform1f(AAStrength, FontConfig.fontAAStrength / 120.f);
+        }
+        try (MemoryStack stack = stackPush()) {
+            final FloatBuffer mvpBuf = stack.mallocFloat(16);
+            GLStateManager.getProjectionMatrix().mul(GLStateManager.getModelViewMatrix(), scratchMvp);
+            scratchMvp.get(mvpBuf);
+            GL20.glUniformMatrix4(mvpMatrixLocation, false, mvpBuf);
         }
 
-        GL13.glClientActiveTexture(GL13.GL_TEXTURE0);
-        GL11.glTexCoordPointer(2, 0, batchVtxTexCoords);
-        GL11.glEnableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
-        GL11.glColorPointer(4, GL11.GL_UNSIGNED_BYTE, 0, batchVtxColors);
-        GL11.glEnableClientState(GL11.GL_COLOR_ARRAY);
-        GL11.glVertexPointer(2, 0, batchVtxPositions);
-        GL11.glEnableClientState(GL11.GL_VERTEX_ARRAY);
-        GLStateManager.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
+        if (fontVAO == 0) {
+            fontVAO = GL30.glGenVertexArrays();
 
-        GL11.glDisableClientState(GL11.GL_NORMAL_ARRAY);
-        GL11.glNormal3f(0.0f, 0.0f, 1.0f);
+            GLStateManager.glBindVertexArray(fontVAO);
+            GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbo);
+
+            ebo.bind();
+
+            // position
+            GL20.glVertexAttribPointer(0, 2, GL11.GL_FLOAT, false, VERTEX_SIZE, 0);
+            GL20.glEnableVertexAttribArray(0);
+
+            // texcoords
+            GL20.glVertexAttribPointer(1, 2, GL11.GL_FLOAT, false, VERTEX_SIZE, 8);
+            GL20.glEnableVertexAttribArray(1);
+
+            // color
+            GL20.glVertexAttribPointer(2, 4, GL11.GL_UNSIGNED_BYTE, true, VERTEX_SIZE, 16);
+            GL20.glEnableVertexAttribArray(2);
+
+            // tex bounds
+            GL20.glVertexAttribPointer(3, 4, GL11.GL_FLOAT, false, VERTEX_SIZE, 20);
+            GL20.glEnableVertexAttribArray(3);
+        }
+
+        GLStateManager.glBindVertexArray(fontVAO);
 
         // Use plain for loop to avoid allocations
         final FontDrawCmd[] cmdsData = batchCommands.elements();
@@ -340,19 +403,14 @@ public class BatchingFontRenderer {
                 }
                 lastTexture = cmd.texture;
             }
-            batchIndices.limit(cmd.startVtx + cmd.idxCount);
-            batchIndices.position(cmd.startVtx);
-
-            GL11.glDrawElements(GL11.GL_TRIANGLES, batchIndices);
-        }
-        if (canUseAA) {
-            GLStateManager.glUseProgram(lastActiveProgram);
-            GL20.glDisableVertexAttribArray(texBoundAttrLocation);
+            GL11.glDrawElements(GL11.GL_TRIANGLES, cmd.idxCount, GL11.GL_UNSIGNED_SHORT, (long) cmd.startVtx * 2L);
         }
 
-        GL11.glDisableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
-        GL11.glDisableClientState(GL11.GL_COLOR_ARRAY);
-        GL11.glDisableClientState(GL11.GL_VERTEX_ARRAY);
+
+        GLStateManager.glUseProgram(prevProgram);
+
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
+        GLStateManager.glBindVertexArray(0);
 
         if (isTextureEnabledBefore) {
         	GLStateManager.glEnable(GL11.GL_TEXTURE_2D);
@@ -361,13 +419,15 @@ public class BatchingFontRenderer {
         	GLStateManager.glBindTexture(GL11.GL_TEXTURE_2D, boundTextureBefore);
         }
 
+        clearBatch();
+    }
+
+    private void clearBatch() {
         // Clear for the next batch
         batchCommandPool.addAll(batchCommands);
         batchCommands.clear();
-        vtxWriterIndex = 0;
+        vertexDataPos = 0;
         idxWriterIndex = 0;
-        batchIndices.limit(batchIndices.capacity());
-        batchIndices.position(0);
     }
 
     // === Actual text mesh generation
@@ -377,7 +437,7 @@ public class BatchingFontRenderer {
     }
 
     public boolean forceDefaults() {
-        return this.isSGA || this.isSplash;
+        return this.bookMode || this.isSGA || this.isSplash;
     }
 
     public float getGlyphScaleX() {
@@ -433,6 +493,7 @@ public class BatchingFontRenderer {
             boolean curUnderline = false;
 
             float glyphScaleY = getGlyphScaleY();
+            float glyphScaleX = getGlyphScaleX();
             float heightNorth = anchorY + (underlying.FONT_HEIGHT - 1.0f) * (0.5f - glyphScaleY / 2);
 
             final float underlineY = heightNorth + (underlying.FONT_HEIGHT - 1.0f) * glyphScaleY;
@@ -508,10 +569,16 @@ public class BatchingFontRenderer {
                     continue;
                 }
 
-                if (FontConfig.enableCustomFont) {
+                if (FontConfig.enableCustomFont && FontConfig.enableGlyphReplacements) {
                     String chrReplacement = GlyphReplacements.customGlyphs.get(String.valueOf(chr));
                     if (chrReplacement != null) {
-                        chr = chrReplacement.charAt(0);
+                        char replacement = chrReplacement.charAt(0);
+                        boolean isReplacementCharAvailable =
+                            FontProviderCustom.getPrimary().isGlyphAvailable(replacement)
+                                || FontProviderCustom.getFallback().isGlyphAvailable(replacement);
+                        if (isReplacementCharAvailable) {
+                            chr = replacement;
+                        }
                     }
                 }
 
@@ -526,14 +593,14 @@ public class BatchingFontRenderer {
 
                 // Check ASCII space, NBSP, NNBSP
                 if (chr == ' ' || chr == '\u00A0' || chr == '\u202F') {
-                    curX += 4 * this.getWhitespaceScale();
+                    curX += 4 * this.getWhitespaceScale() + (curBold ? 1 : 0);
                     continue;
                 }
 
                 final float uStart = fontProvider.getUStart(chr);
                 final float vStart = fontProvider.getVStart(chr);
-                final float xAdvance = fontProvider.getXAdvance(chr) * getGlyphScaleX();
-                final float glyphW = fontProvider.getGlyphW(chr) * getGlyphScaleX();
+                final float xAdvance = fontProvider.getXAdvance(chr) * glyphScaleX;
+                final float glyphW = fontProvider.getGlyphW(chr) * glyphScaleX;
                 final float uSz = fontProvider.getUSize(chr);
                 final float vSz = fontProvider.getVSize(chr);
                 final float itOff = curItalic ? 1.0F : 0.0F; // italic offset
@@ -576,7 +643,8 @@ public class BatchingFontRenderer {
                 final int vtxCount = 4 * charCount;
                 pushDrawCmd(idxId, vtxCount / 2 * 3, texture, chr > 255);
 
-                curX += (xAdvance + (curBold ? shadowOffset : 0.0f)) + getGlyphSpacing();
+                curX += (xAdvance + (curBold ? 1.0f : 0.0f)) + getGlyphSpacing();
+                if (bookMode) { curX = (int) curX; }
                 underlineEndX = curX;
                 strikethroughEndX = curX;
             }

src/main/java/com/gtnewhorizons/angelica/client/font/FontProviderCustom.java

@@ -1,6 +1,5 @@
 package com.gtnewhorizons.angelica.client.font;
 
-import com.gtnewhorizon.gtnhlib.config.ConfigurationManager;
 import com.gtnewhorizons.angelica.config.FontConfig;
 import lombok.Setter;
 import lombok.Value;
@@ -46,7 +45,7 @@ public final class FontProviderCustom implements FontProvider {
             default -> null;
         };
         if (Objects.equals(myFontName, "(none)")) {
-            font = null;
+            this.font = null;
             return;
         }
         int fontPos = -1;
@@ -58,10 +57,10 @@ public final class FontProviderCustom implements FontProvider {
         }
         if (fontPos == -1) {
             LOGGER.info("Could not find previously set font \"{}\". ", myFontName);
-            font = null;
+            this.font = null;
             return;
         }
-        font = availableFonts[fontPos].deriveFont(currentFontQuality);
+        this.font = availableFonts[fontPos].deriveFont(this.currentFontQuality);
     }
     private static class InstLoader {
         static final FontProviderCustom instance0 = new FontProviderCustom((byte)0);
@@ -71,8 +70,8 @@ public final class FontProviderCustom implements FontProvider {
     public static FontProviderCustom getFallback() { return InstLoader.instance1; }
 
     public void reloadFont(int fontID) {
-        currentFontQuality = FontConfig.customFontQuality;
-        font = FontStrategist.getAvailableFonts()[fontID].deriveFont(currentFontQuality);
+        this.currentFontQuality = FontConfig.customFontQuality;
+        this.font = FontStrategist.getAvailableFonts()[fontID].deriveFont(this.currentFontQuality);
 
         File[] files = new File(getFontDir()).listFiles();
         if (files != null) {
@@ -94,7 +93,7 @@ public final class FontProviderCustom implements FontProvider {
             }
         }
 
-        fontAtlases = new FontAtlas[ATLAS_COUNT];
+        this.fontAtlases = new FontAtlas[ATLAS_COUNT];
     }
 
     private String getFontDir() {
@@ -134,50 +133,44 @@ public final class FontProviderCustom implements FontProvider {
         }
 
         void construct(Font font) {
-            float separator = currentFontQuality / 3f;
+            int atlasChars = 0;
+            for (int i = 0; i < ATLAS_SIZE; i++) {
+                final char ch = (char) (i + ATLAS_SIZE * this.id);
+                if (font.canDisplay(ch)) { atlasChars++; }
+            }
+            if (atlasChars == 0) { return; }
 
             BufferedImage image = new BufferedImage(1, 1, BufferedImage.TYPE_INT_ARGB);
             Graphics2D g2d = image.createGraphics();
             g2d.setFont(font);
             FontMetrics fm = g2d.getFontMetrics();
             g2d.dispose();
-            int width = 0;
-            int actualChars = 0;
-            for (int i = 0; i < ATLAS_SIZE; i++) {
-                final char ch = (char)(i + ATLAS_SIZE * this.id);
-                if (font.canDisplay(ch)) {
-                    width += (int) (separator + fm.charWidth(ch));
-                    actualChars++;
-                }
-            }
-            if (actualChars == 0) {
-                return;
-            }
-            final int atlasTilesX = (int) Math.ceil(Math.sqrt(actualChars) * 1.5f);
-            final int atlasTilesY = (int) Math.ceil((double) actualChars / atlasTilesX);
-            LOGGER.info("constructing custom font atlas (ID {}) of nominal size {} chars, actual: {}, {} rows by {} columns",
-                this.id, ATLAS_SIZE, actualChars, atlasTilesX, atlasTilesY);
-            width = 0;
-            actualChars = 0;
+
+            final int atlasTilesX = (int) Math.ceil(Math.sqrt(atlasChars) * 1.5f);
+            final int atlasTilesY = (int) Math.ceil((double) atlasChars / atlasTilesX);
+            final float charSeparator = currentFontQuality / 3f;
+            int rowWidth = 0;
             int maxRowWidth = 0;
+            atlasChars = 0;
+
             for (int i = 0; i < ATLAS_SIZE; i++) {
-                if (actualChars % atlasTilesX == 0) {
-                    maxRowWidth = Math.max(maxRowWidth, width);
-                    width = 0;
+                if (atlasChars % atlasTilesX == 0) {
+                    maxRowWidth = Math.max(maxRowWidth, rowWidth);
+                    rowWidth = 0;
                 }
                 final char ch = (char)(i + ATLAS_SIZE * this.id);
                 if (font.canDisplay(ch)) {
-                    width += (int) (separator + fm.charWidth(ch));
-                    actualChars++;
+                    rowWidth += (int) (charSeparator + fm.charWidth(ch));
+                    atlasChars++;
                 }
             }
-            maxRowWidth = Math.max(maxRowWidth, width);
+            maxRowWidth = Math.max(maxRowWidth, rowWidth);
 
             final int lineHeight = fm.getHeight();
             final float desc = fm.getDescent();
 
-            final int imageWidth = (int) (maxRowWidth + separator);
-            final int imageHeight = (int) ((separator + lineHeight) * atlasTilesY + separator);
+            final int imageWidth = (int) (maxRowWidth + charSeparator);
+            final int imageHeight = (int) ((charSeparator + lineHeight) * atlasTilesY + charSeparator);
 
             image = new BufferedImage(imageWidth, imageHeight, BufferedImage.TYPE_INT_ARGB);
             g2d = image.createGraphics();
@@ -192,35 +185,34 @@ public final class FontProviderCustom implements FontProvider {
             fm = g2d.getFontMetrics();
 
             int tileX = 0, tileY = 0; // position in atlas tiles
-            int imgX = (int) separator; // position in pixels
+            int imgX = (int) charSeparator; // position in pixels
 
             for (int i = 0; i < ATLAS_SIZE; i++) {
-                final char ch = (char)(i + ATLAS_SIZE * this.id);
+                final char ch = (char) (i + ATLAS_SIZE * this.id);
                 if (!font.canDisplay(ch)) { continue; }
 
                 if (tileX >= atlasTilesX) {
                     tileX = 0;
-                    imgX = (int) separator;
+                    imgX = (int) charSeparator;
                     tileY++;
                 }
 
                 final int charWidth = fm.charWidth(ch);
                 final float charAspectRatio = (float) charWidth / lineHeight;
                 final float inset = currentFontQuality / 16;
-                g2d.drawString(Character.toString(ch), imgX, (lineHeight + separator) * (tileY + 1) - desc);
+                g2d.drawString(Character.toString(ch), imgX, (lineHeight + charSeparator) * (tileY + 1) - desc);
                 final float uStart = (float) (imgX - inset * charAspectRatio) / imageWidth;
-                final float vStart = ((lineHeight + separator) * (tileY + 1) - lineHeight - inset) / imageHeight;
+                final float vStart = ((lineHeight + charSeparator) * (tileY + 1) - lineHeight - inset) / imageHeight;
                 final float xAdvance = charAspectRatio * 8 * charWidth / (charWidth + 2 * inset * charAspectRatio);
                 final float glyphW = charAspectRatio * 8 + 1;
                 final float uSz = (float) (charWidth + 2 * inset * charAspectRatio) / imageWidth;
                 final float vSz = (float) (lineHeight + 2 * inset) / imageHeight;
-                glyphData[i] = new GlyphData(uStart, vStart, xAdvance, glyphW, uSz, vSz);
-                imgX += (int) (charWidth + separator);
+                this.glyphData[i] = new GlyphData(uStart, vStart, xAdvance, glyphW, uSz, vSz);
+                imgX += (int) (charWidth + charSeparator);
                 tileX++;
             }
             g2d.dispose();
             try {
-                LOGGER.info("writing custom font atlas texture ({}x{} px) to {}", imageWidth, imageHeight, getAtlasFullPath(this.id));
                 Files.createDirectories(Paths.get(getFontDir()));
                 ImageIO.write(image, "png", new File(getAtlasFullPath(this.id)));
             } catch (IOException e) {
@@ -232,18 +224,18 @@ public final class FontProviderCustom implements FontProvider {
 
     private FontAtlas getAtlas(char chr) {
         int id = chr / ATLAS_SIZE;
-        FontAtlas fa = fontAtlases[id];
+        FontAtlas fa = this.fontAtlases[id];
         if (fa == null) {
             fa = new FontAtlas(id);
-            fa.construct(font);
+            fa.construct(this.font);
+            this.fontAtlases[id] = fa;
         }
-        fontAtlases[id] = fa;
         return fa;
     }
 
     @Override
     public boolean isGlyphAvailable(char chr) {
-        if (font == null) { return false; }
+        if (this.font == null) { return false; }
         return (getAtlas(chr).glyphData[chr % ATLAS_SIZE] != null);
     }
 

src/main/java/com/gtnewhorizons/angelica/client/font/FontProviderMC.java

@@ -28,16 +28,14 @@ public final class FontProviderMC implements FontProvider {
     public int[] charWidth;
 
     static {
+        MCFONT_ASCII_MAP.defaultReturnValue((short) -1);
         for (short i = 0; i < MCFONT_CHARS.length(); i++) {
             MCFONT_ASCII_MAP.put(MCFONT_CHARS.charAt(i), i);
         }
     }
 
     public int lookupMcFontPosition(char ch) {
-        if (isGlyphAvailable(ch)) {
-            return MCFONT_ASCII_MAP.get(ch);
-        }
-        return -1;
+        return MCFONT_ASCII_MAP.get(ch);
     }
 
     @Override

src/main/java/com/gtnewhorizons/angelica/client/font/FontProviderUnicode.java

@@ -1,16 +1,31 @@
 package com.gtnewhorizons.angelica.client.font;
 
 import com.gtnewhorizons.angelica.config.FontConfig;
+import net.minecraft.client.Minecraft;
 import net.minecraft.util.ResourceLocation;
 
+import java.io.IOException;
+import java.io.InputStream;
+
 public final class FontProviderUnicode implements FontProvider {
 
-    private FontProviderUnicode() {}
+    private FontProviderUnicode() {
+        try {
+            InputStream inputstream = Minecraft.getMinecraft().getResourceManager()
+                .getResource(new ResourceLocation("font/glyph_sizes.bin")).getInputStream();
+            //noinspection ResultOfMethodCallIgnored
+            inputstream.read(this.glyphWidth);
+        }
+        catch (IOException ioexception) {
+            throw new RuntimeException(ioexception);
+        }
+    }
+
     private static class InstLoader { static final FontProviderUnicode instance = new FontProviderUnicode(); }
     public static FontProviderUnicode get() { return FontProviderUnicode.InstLoader.instance; }
 
     private static final ResourceLocation[] unicodePageLocations = new ResourceLocation[256];
-    public byte[] glyphWidth;
+    private final byte[] glyphWidth = new byte[65536];
 
     private ResourceLocation getUnicodePageLocation(int page) {
         final ResourceLocation lookup = unicodePageLocations[page];
@@ -82,7 +97,7 @@ public final class FontProviderUnicode implements FontProvider {
 
     @Override
     public float getShadowOffset() {
-        return FontConfig.fontShadowOffset;
+        return FontConfig.fontShadowOffset * FontConfig.fontShadowOffsetUC;
     }
 
     @Override

src/main/java/com/gtnewhorizons/angelica/client/font/FontStrategist.java

@@ -72,17 +72,19 @@ public class FontStrategist {
         DefaultResourcePack fontResourcePack = new DefaultResourcePack(packMap);
         List defaultResourcePacks = ((ResourceAccessor) Minecraft.getMinecraft()).angelica$getDefaultResourcePacks();
         defaultResourcePacks.add(fontResourcePack);
-        Minecraft.getMinecraft().refreshResources();
     }
 
     /**
-     Lets you get a FontProvider per char while respecting font priority and fallbacks, the unicode flag, whether or not
+     Lets you get a FontProvider per char while respecting font priority and fallbacks, the unicode flag, whether
      SGA is on, if we're in a splash screen, if a font can even display a character in the first place, etc.
      */
     public static FontProvider getFontProvider(BatchingFontRenderer me, char chr, boolean customFontEnabled, boolean forceUnicode) {
         if (me.isSGA && FontProviderMC.get(true).isGlyphAvailable(chr)) {
             return FontProviderMC.get(true);
         }
+        if (me.bookMode) {
+            return FontProviderUnicode.get();
+        }
         if (customFontEnabled && !me.isSplash) {
             FontProvider fp;
             fp = FontProviderCustom.getPrimary();

src/main/java/com/gtnewhorizons/angelica/client/gui/FontConfigScreen.java

@@ -38,7 +38,7 @@ public class FontConfigScreen extends GuiScreen {
     private ArrayList<Font> displayedFonts;
     private GuiTextField searchBox;
     private GuiTextField testArea;
-    private int sliderPages = 0;
+    private int lastSliderPageIndex = 0;
     private int displayedSliderPage = 0;
     private final int sliderWidth = 160;
     private final int sliderHeight = 20;
@@ -58,6 +58,7 @@ public class FontConfigScreen extends GuiScreen {
     SliderClone.Option optFontAAMode = new SliderClone.Option(0, 2, 1);
     SliderClone.Option optFontAAStrength = new SliderClone.Option(1, 24, 1);
     SliderClone.Option optCustomFontScale = new SliderClone.Option(0.1f, 3, 0.05f);
+    SliderClone.Option optShadowOffsetUC = new SliderClone.Option(0, 2, 0.05f);
 
     public FontConfigScreen(GuiScreen parent) {
         this.title = I18n.format("options.angelica.fontconfig.title");
@@ -226,6 +227,16 @@ public class FontConfigScreen extends GuiScreen {
             .formatString("x%3.2f")
             .build()
         );
+        sliders.add(new SliderClone.SliderCloneBuilder()
+            .width(sliderWidth)
+            .height(sliderHeight)
+            .option(optShadowOffsetUC)
+            .initialValue(FontConfig.fontShadowOffsetUC)
+            .setter(value -> FontConfig.fontShadowOffsetUC = value)
+            .langKey("options.angelica.fontconfig.shadow_offset_unicode")
+            .formatString("x%3.2f")
+            .build()
+        );
 
         final int halfWidth = this.width / 2;
         final int sliderSpacing = 4;
@@ -236,11 +247,11 @@ public class FontConfigScreen extends GuiScreen {
         final int y1 = this.height - 65;
         final int y2 = this.height - 65 + sliderHeight + sliderSpacing;
 
-        this.sliderPages = sliders.size() / 6;
-        this.displayedSliderPage = Math.min(this.displayedSliderPage, this.sliderPages);
+        this.lastSliderPageIndex = (sliders.size() - 1) / 6;
+        this.displayedSliderPage = Math.min(this.displayedSliderPage, this.lastSliderPageIndex);
 
         this.backButton.enabled = (this.displayedSliderPage != 0);
-        this.fwdButton.enabled = (this.displayedSliderPage != this.sliderPages);
+        this.fwdButton.enabled = (this.displayedSliderPage != this.lastSliderPageIndex);
 
         final int start = 6 * this.displayedSliderPage;
         final int end = Math.min(6 * (this.displayedSliderPage + 1), sliders.size());
@@ -304,7 +315,7 @@ public class FontConfigScreen extends GuiScreen {
     }
 
     private void switchPage(int offset) {
-        this.displayedSliderPage = MathHelper.clamp_int(this.displayedSliderPage + offset, 0, this.sliderPages);
+        this.displayedSliderPage = MathHelper.clamp_int(this.displayedSliderPage + offset, 0, this.lastSliderPageIndex);
         this.buttonList.removeIf(guiButton -> guiButton instanceof SliderClone);
         this.initSliders();
     }

src/main/java/com/gtnewhorizons/angelica/client/gui/SliderClone.java

@@ -1,12 +1,12 @@
 package com.gtnewhorizons.angelica.client.gui;
 
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import lombok.AllArgsConstructor;
 import lombok.Setter;
 import lombok.experimental.Accessors;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.GuiButton;
 import net.minecraft.client.resources.I18n;
-import org.lwjgl.opengl.GL11;
 
 import java.util.function.Consumer;
 import java.util.function.Function;
@@ -123,7 +123,7 @@ public class SliderClone extends GuiButton {
                 this.displayString = displayStringFormatter.apply(f);
             }
 
-            GL11.glColor4f(1.0F, 1.0F, 1.0F, 1.0F);
+            GLStateManager.glColor4f(1.0F, 1.0F, 1.0F, 1.0F);
             this.drawTexturedModalRect(this.xPosition + (int)(this.sliderPercentage * (float)(this.width - 8)), this.yPosition, 0, 66, 4, 20);
             this.drawTexturedModalRect(this.xPosition + (int)(this.sliderPercentage * (float)(this.width - 8)) + 4, this.yPosition, 196, 66, 4, 20);
         }

src/main/java/com/gtnewhorizons/angelica/compat/DriverCompatabilityCheck.java

@@ -0,0 +1,55 @@
+package com.gtnewhorizons.angelica.compat;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.lwjgl.opengl.ARBDebugOutput;
+import org.lwjgl.opengl.GL11;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+
+/**
+ * Checks for known problematic driver configurations and applies workarounds. Adapted from Embeddium/Sodium's LateDriverScanner.
+ *
+ * <p>The NVIDIA workaround can be disabled via: {@code -Dangelica.disableNvidiaWorkaround=true}
+ */
+public class DriverCompatabilityCheck {
+    private static final Logger LOGGER = LogManager.getLogger("Angelica");
+
+    private static final boolean DISABLE_NVIDIA_WORKAROUND = Boolean.getBoolean("angelica.disableNvidiaWorkaround");
+
+    /**
+     * Should be called after GL context is created and GLStateManager is initialized.
+     */
+    public static void checkDriverCompatibility() {
+        final String vendor = GL11.glGetString(GL11.GL_VENDOR);
+        final String renderer = GL11.glGetString(GL11.GL_RENDERER);
+        final String version = GL11.glGetString(GL11.GL_VERSION);
+
+        LOGGER.info("OpenGL Vendor: {}", vendor);
+        LOGGER.info("OpenGL Renderer: {}", renderer);
+        LOGGER.info("OpenGL Version: {}", version);
+
+        if (vendor != null && vendor.contains("NVIDIA")) {
+            if (DISABLE_NVIDIA_WORKAROUND) {
+                LOGGER.info("NVIDIA workaround disabled via -Dangelica.disableNvidiaWorkaround=true");
+            } else {
+                applyNvidiaWorkaround();
+            }
+        }
+    }
+
+    /**
+     * https://github.com/godotengine/godot/issues/33969#issuecomment-917846774
+     * Attempt to force the driver to disable its submission thread by enabling synchronous debug output.
+     * This usually suppresses bad behavior from NVIDIA's "Threaded Optimizations" feature.
+     */
+    private static void applyNvidiaWorkaround() {
+        if (!GLStateManager.capabilities.GL_ARB_debug_output) {
+            LOGGER.warn("Cannot apply NVIDIA workaround: ARB_debug_output not available");
+            return;
+        }
+
+        LOGGER.info("Enabling workaround for NVIDIA threaded optimizations");
+        GL11.glEnable(ARBDebugOutput.GL_DEBUG_OUTPUT_SYNCHRONOUS_ARB);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/compat/ExtendedBlockStorageExt.java

@@ -6,7 +6,6 @@ import com.gtnewhorizons.neid.mixins.interfaces.IExtendedBlockStorageMixin;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.NibbleArray;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
-import ru.fewizz.idextender.Hooks;
 
 public class ExtendedBlockStorageExt extends ExtendedBlockStorage {
     public boolean hasSky;
@@ -39,12 +38,6 @@ public class ExtendedBlockStorageExt extends ExtendedBlockStorage {
                     System.arraycopy(((IExtendedBlockStorageMixin)(Object)storage).getBlock16BMetaArray(), 0, block16BMetaArray, 0, block16BMetaArray.length);
                 }
             }
-            else if (ModStatus.isOldNEIDLoaded){
-                final short[] blockLSBArray = Hooks.get(this);
-                System.arraycopy(Hooks.get(storage), 0, blockLSBArray, 0, blockLSBArray.length);
-                // getBlockMSBArray is nuked in asm version
-                arrayLen = blockLSBArray.length;
-            }
             else {
                 final byte[] blockLSBArray = this.getBlockLSBArray();
                 System.arraycopy(storage.getBlockLSBArray(), 0, blockLSBArray, 0, blockLSBArray.length);

src/main/java/com/gtnewhorizons/angelica/compat/ModStatus.java

@@ -11,16 +11,8 @@ import org.apache.logging.log4j.Logger;
 public class ModStatus {
     public static final Logger LOGGER = LogManager.getLogger("ModCompat");
 
-    public static BackhandReflectionCompat backhandCompat;
-    /**
-     * Mixin Version
-     */
-    public static boolean isNEIDLoaded;
-    /**
-     * ASM Version
-     */
-    public static boolean isOldNEIDLoaded;
     public static boolean isBetterCrashesLoaded;
+    public static boolean isNEIDLoaded;
     public static boolean isNEIDMetadataExtended;
     public static boolean isLotrLoaded;
     public static boolean isChunkAPILoaded;
@@ -34,15 +26,13 @@ public class ModStatus {
     public static boolean isBaublesLoaded;
     public static boolean isFluidLoggedLoaded;
 
-    public static void preInit(){
-        isBackhandLoaded = Loader.isModLoaded("backhand");
-        if(isBackhandLoaded) {
+    public static void preInit() {
+        if (Loader.isModLoaded("backhand")) {
             isBackhandLoaded = BackhandReflectionCompat.isBackhandLoaded();
         }
 
         isBetterCrashesLoaded = Loader.isModLoaded("bettercrashes");
         isNEIDLoaded = Loader.isModLoaded("neid");
-        isOldNEIDLoaded = Loader.isModLoaded("notenoughIDs");
         isLotrLoaded = Loader.isModLoaded("lotr");
         isChunkAPILoaded = Loader.isModLoaded("chunkapi");
         isEIDBiomeLoaded = Loader.isModLoaded("endlessids_biome");

src/main/java/com/gtnewhorizons/angelica/compat/iris/ModdedBiomeDetector.java

@@ -1,5 +1,6 @@
 package com.gtnewhorizons.angelica.compat.iris;
 
+import com.gtnewhorizons.angelica.compat.ModStatus;
 import net.coderbot.iris.parsing.BiomeCategories;
 import net.minecraft.world.biome.BiomeGenBase;
 
@@ -8,7 +9,7 @@ import java.util.Map;
 
 /**
  * Detects and categorizes biomes from popular modded biome mods using cached class checks.
- * Currently supports: BiomesOPlenty (BOP), Realistic World Gen (RWG)
+ * Currently supports: BiomesOPlenty (BOP), Realistic World Gen (RWG), lotr (b36.15)
  */
 public class ModdedBiomeDetector {
     private static boolean initialized = false;
@@ -23,12 +24,15 @@ public class ModdedBiomeDetector {
     // LinkedHashMap maintains insertion order for deterministic behavior
     private static final Map<Class<?>, BiomeCategories> rwgClassMap = new LinkedHashMap<>();
 
+    private static Class<?> lotrBiomeClass = null;
+
     private static synchronized void initialize() {
         if (initialized) return;
         initialized = true;
 
         initializeBOP();
         initializeRWG();
+        initializeLOTR();
     }
 
     private static void initializeBOP() {
@@ -59,6 +63,16 @@ public class ModdedBiomeDetector {
         tryAddRWGClass("rwg.biomes.base.BaseBiomeSnowForest", BiomeCategories.TAIGA); // Snow forests are taiga
     }
 
+    private static void initializeLOTR() {
+        if (ModStatus.isLotrLoaded) {
+            try {
+                lotrBiomeClass = Class.forName("lotr.common.world.biome.LOTRBiome");
+            } catch (ClassNotFoundException ignored) {
+                // lotr not installed
+            }
+        }
+    }
+
     private static void tryAddRWGClass(String className, BiomeCategories category) {
         try {
             final Class<?> clazz = Class.forName(className);
@@ -91,12 +105,64 @@ public class ModdedBiomeDetector {
         // fall through to name/property-based detection
 
         // Realistic World Gen detection
-        for (Map.Entry<Class<?>, BiomeCategories> entry : rwgClassMap.entrySet()) {
-            if (entry.getKey().isInstance(biome)) {
-                return entry.getValue();
+        if (biome.getBiomeClass().getName().contains("rwg.biomes")) {
+            for (Map.Entry<Class<?>, BiomeCategories> entry : rwgClassMap.entrySet()) {
+                if (entry.getKey().isInstance(biome)) {
+                    return entry.getValue();
+                }
             }
         }
 
+        // lotr
+        if (lotrBiomeClass!= null && lotrBiomeClass.isInstance(biome)) {
+            return detectLOTRBiome(biome);
+        }
+
         return null;
     }
+
+    private static BiomeCategories detectLOTRBiome(BiomeGenBase biome) {
+        return switch (biome.biomeName) {
+            case "river", "farHaradJungleLake", "lake" -> BiomeCategories.RIVER;
+            case "rohan", "rivendell", "rhunIsland", "rhunLandHills", "rhunLandSteppe", "rhunLand", "andrast",
+                 "blackrootVale", "lamedon", "imlothMelui", "towerHills", "dorwinion", "dale", "shireMoors", "wold",
+                 "anduinVale", "rhun", "lebennin", "pertorogwaith", "breeland", "island", "pinnathGelin",
+                 "minhiriath", "pelennor", "adornland", "nanCurunir", "ithilienWasteland", "fangornClearing",
+                 "barrowDowns", "dorEnErnilHills", "dorEnErnil", "nurn", "wilderland", "eastBight", "lindon",
+                 "eregion", "enedwaith", "meneltarma", "anduinHills", "eriador", "angle", "loneLandsHills",
+                 "loneLands", "pelargir", "rohanUrukHighlands", "celebrant", "gondor", "shire", "nurnen", "farHarad" ->
+                BiomeCategories.PLAINS;
+            case "mistyMountains", "windMountains", "farHaradVolcano", "redMountains", "haradMountains",
+                 "angmarMountains", "blueMountains", "greyMountains", "whiteMountains", "mordorMountains" ->
+                BiomeCategories.MOUNTAIN;
+            case "shireWoodlands", "rhunIslandForest", "rhunRedForest", "pukel", "lossarnach", "gulfHaradForest",
+                 "nearHaradFertileForest", "dolGuldur", "rhunForest", "tauredainClearing", "umbarForest",
+                 "farHaradForest", "chetwood", "woodlandRealmHills", "mirkwoodNorth", "whiteDowns", "ithilienHills",
+                 "gondorWoodlands", "rohanWoodlands", "fangornWasteland", "mirkwoodMountains", "lindonWoodlands",
+                 "lothlorienEdge", "erynVorn", "oldForest", "fangorn", "dunland", "ithilien", "mirkwoodCorrupted",
+                 "woodlandRealm", "trollshaws", "lothlorien", "farHaradKanuka" -> BiomeCategories.FOREST;
+            case "mordor", "lastDesert", "harnedor", "easternDesolation", "morgulVale", "gorgoroth", "udun",
+                 "nearHaradRedDesert", "nearHaradSemiDesert", "lostladen",
+                 "nearHaradHills", "nearHarad", "nanUngol", "dagorlad", "brownLands" -> BiomeCategories.DESERT;
+            case "ironHills", "rivendellHills", "windMountainsFoothills", "lamedonHills", "redMountainsFoothills",
+                 "tolfalas", "dorwinionHills", "whiteMountainsFoothills", "blueMountainsFoothills",
+                 "greyMountainsFoothills", "mistyMountainsFoothills", "erebor", "angmar", "eriadorDowns",
+                 "ettenmoors", "emynMuil" -> BiomeCategories.EXTREME_HILLS;
+            case "deadMarshes", "shireMarshes", "farHaradMangrove", "farHaradSwamp", "swanfleet", "nindalf",
+                 "longMarshes", "entwashMouth", "nurnMarshes", "gladdenFields", "midgewater", "anduinMouth" ->
+                BiomeCategories.SWAMP;
+            case "harondor", "nearHaradOasis", "nearHaradRiverbank", "farHaradBushlandHills", "farHaradBushland",
+                 "gulfHarad", "nearHaradFertile", "umbarHills", "umbar", "farHaradAridHills", "farHaradArid" ->
+                BiomeCategories.SAVANNA;
+            case "ocean" -> BiomeCategories.OCEAN;
+            case "forodwaith", "forodwaithGlacier", "tundra", "forodwaithMountains" -> BiomeCategories.ICY;
+            case "lindonCoast", "beachWhite", "farHaradCoast", "forodwaithCoast", "beachGravel", "beach" ->
+                BiomeCategories.BEACH;
+            case "coldfells", "wilderlandNorth", "taiga" -> BiomeCategories.TAIGA;
+            case "farHaradJungle", "halfTrollForest", "farHaradJungleMountains",
+                 "farHaradCloudForest", "farHaradJungleEdge" -> BiomeCategories.JUNGLE;
+            case "utumno" -> BiomeCategories.NONE;
+            default -> null;
+        };
+    }
 }

src/main/java/com/gtnewhorizons/angelica/compat/mojang/Camera.java

@@ -19,6 +19,7 @@ public class Camera {
     public static final Camera INSTANCE = new Camera();
 
     private final Vector3d pos = new Vector3d();
+    private final Vector3d entityPos = new Vector3d();
     private final BlockPos blockPos = new BlockPos();
     private final Vector3f offset = new Vector3f();
     private final Matrix4f inverseModelView = new Matrix4f();
@@ -42,12 +43,14 @@ public class Camera {
         this.partialTicks = partialTicks;
         this.entity = entity;
 
-        // Entity position (interpolated, at feet level)
+        // Entity position (interpolated, at eye level)
         final double entityX = entity.lastTickPosX + (entity.posX - entity.lastTickPosX) * partialTicks;
         final double entityY = entity.lastTickPosY + (entity.posY - entity.lastTickPosY) * partialTicks;
         final double entityZ = entity.lastTickPosZ + (entity.posZ - entity.lastTickPosZ) * partialTicks;
         final double eyeHeight = entity.getEyeHeight();
 
+        entityPos.set(entityX, entityY + eyeHeight, entityZ);
+
         thirdPerson = Minecraft.getMinecraft().gameSettings.thirdPersonView > 0;
 
         final double camX, camY, camZ;

src/main/java/com/gtnewhorizons/angelica/compat/mojang/InteractionHand.java

@@ -2,6 +2,7 @@ package com.gtnewhorizons.angelica.compat.mojang;
 
 
 import com.gtnewhorizons.angelica.compat.ModStatus;
+import com.gtnewhorizons.angelica.compat.backhand.BackhandReflectionCompat;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemStack;
 
@@ -9,14 +10,10 @@ public enum InteractionHand {
     MAIN_HAND,
     OFF_HAND;
 
-    InteractionHand() {
-    }
-
-    public ItemStack getItemInHand(EntityPlayer player){
-        if (ModStatus.isBackhandLoaded && this == InteractionHand.OFF_HAND){ // off hand (requires backhand)
-            return ModStatus.backhandCompat.getOffhandItem(player);
-        }
-        else { // main hand
+    public ItemStack getItemInHand(EntityPlayer player) {
+        if (ModStatus.isBackhandLoaded && this == InteractionHand.OFF_HAND) { // off hand (requires backhand)
+            return BackhandReflectionCompat.getOffhandItem(player);
+        } else { // main hand
             return player.getHeldItem();
         }
     }

src/main/java/com/gtnewhorizons/angelica/compat/toremove/RenderPhase.java

@@ -1,7 +1,7 @@
 package com.gtnewhorizons.angelica.compat.toremove;
 
+import com.gtnewhorizons.angelica.AngelicaMod;
 import com.gtnewhorizons.angelica.glsm.GLStateManager;
-import me.jellysquid.mods.sodium.client.SodiumClientMod;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.texture.TextureManager;
 import net.minecraft.client.renderer.texture.TextureMap;
@@ -147,7 +147,7 @@ public abstract class RenderPhase {
         FOG = new Fog("fog", () -> {
             // Unclear what this should do
             // BackgroundRenderer.setFogBlack(), also levelFogColor()
-            SodiumClientMod.LOGGER.debug("Fog - Not setting level fog color");
+            AngelicaMod.LOGGER.debug("Fog - Not setting level fog color");
             GLStateManager.enableFog();
         }, GLStateManager::disableFog);
         BLACK_FOG = new Fog("black_fog", () -> {
@@ -156,7 +156,7 @@ public abstract class RenderPhase {
         }, () -> {
             // Unclear what this should do
             // BackgroundRenderer.setFogBlack(), also levelFogColor()
-            SodiumClientMod.LOGGER.debug("Fog - Not setting level fog color");
+            AngelicaMod.LOGGER.debug("Fog - Not setting level fog color");
             GLStateManager.disableFog();
         });
         MAIN_TARGET = new Target("main_target", () -> {
@@ -164,7 +164,7 @@ public abstract class RenderPhase {
         });
         OUTLINE_TARGET = new Target("outline_target", () -> {
             // TODO: Sodium
-            SodiumClientMod.LOGGER.debug("NOT enabling the entity outline framebuffer");
+            AngelicaMod.LOGGER.debug("NOT enabling the entity outline framebuffer");
             //MinecraftClient.getInstance().worldRenderer.getEntityOutlinesFramebuffer().beginWrite(false);
         }, () -> {
             Minecraft.getMinecraft().getFramebuffer().bindFramebuffer(false);
@@ -172,7 +172,7 @@ public abstract class RenderPhase {
         TRANSLUCENT_TARGET = new Target("translucent_target", () -> {
             if (Minecraft.isFancyGraphicsEnabled()) {
                 // TODO: Sodium
-                SodiumClientMod.LOGGER.debug("NOT enabling the translucent framebuffer");
+                AngelicaMod.LOGGER.debug("NOT enabling the translucent framebuffer");
                 // MinecraftClient.getInstance().worldRenderer.getTranslucentFramebuffer().beginWrite(false);
             }
 
@@ -345,7 +345,7 @@ public abstract class RenderPhase {
             super("lightmap", () -> {
                 if (lightmap) {
                     // TODO: Sodium - LightmapTextureManager
-                    SodiumClientMod.LOGGER.debug("Lightmap - enable (not implemented)");
+                    AngelicaMod.LOGGER.debug("Lightmap - enable (not implemented)");
 //                    throw new RuntimeException("Not Implemented Yet");
 //                    MinecraftClient.getInstance().gameRenderer.getLightmapTextureManager().enable();
 
@@ -354,7 +354,7 @@ public abstract class RenderPhase {
             }, () -> {
                 if (lightmap) {
                     // TODO: Sodium - LightmapTextureManager
-                    SodiumClientMod.LOGGER.debug("Lightmap - disable (not implemented)");
+                    AngelicaMod.LOGGER.debug("Lightmap - disable (not implemented)");
 //                    throw new RuntimeException("Not Implemented Yet");
 //                    MinecraftClient.getInstance().gameRenderer.getLightmapTextureManager().disable();
                 }

src/main/java/com/gtnewhorizons/angelica/config/AngelicaConfig.java

@@ -48,6 +48,11 @@ public class AngelicaConfig {
     @Config.RequiresMcRestart
     public static boolean enableMCPatcherForgeFeatures;
 
+    @Config.Comment("Replace main menu panorama with modern equivalent.")
+    @Config.DefaultBoolean(true)
+    @Config.RequiresMcRestart
+    public static boolean enablePanoramaBlurShader;
+
     @Config.Comment("Replace cloud renderer with a VBO version.")
     @Config.DefaultBoolean(true)
     @Config.RequiresMcRestart
@@ -88,12 +93,16 @@ public class AngelicaConfig {
     @Config.RequiresMcRestart
     public static boolean enableHudCachingEventTransformer;
 
+    @Config.Comment("Enable HUD Caching at runtime. Requires enableHudCaching to be on at startup. [Experimental]")
+    @Config.DefaultBoolean(false)
+    public static boolean hudCachingActive;
+
     @Config.Comment("The amount of frames to wait before updating the HUD elements. [Experimental]")
     @Config.DefaultInt(20)
     @Config.RangeInt(min = 1, max = 60)
     public static int hudCachingFPS = 20;
 
-    @Config.Comment("Batch drawScreen fonts [Experimental]")
+    @Config.Comment("Batch drawScreen fonts")
     @Config.DefaultBoolean(true)
     @Config.RequiresMcRestart
     public static boolean enableFontRenderer;
@@ -108,7 +117,7 @@ public class AngelicaConfig {
     @Config.RequiresMcRestart
     public static boolean optimizeWorldUpdateLight;
 
-    @Config.Comment("Speedup Animations. [From Hodgepodge]")
+    @Config.Comment("Optimize Texture Animations. [From Hodgepodge]")
     @Config.DefaultBoolean(true)
     @Config.RequiresMcRestart
     public static boolean speedupAnimations;
@@ -200,7 +209,7 @@ public class AngelicaConfig {
             "net.minecraft.block.BlockStairs"
     })
     public static String[] blockCrackFixBlacklist;
-    
+
     @Config.Comment({"Block classes that have render pass other than 0 but still need to be manipulated.",
                      "Add a block class here if you see flickering (z-fighting) with fixBlockCrack enabled"
     })
@@ -210,6 +219,8 @@ public class AngelicaConfig {
             "shukaro.artifice.block.world.BlockOre",
             "bartworks.system.material.BWMetaGeneratedOres",
             "gtPlusPlus.core.block.base.BlockBaseOre",
+            "org.pfaa.geologica.block.BrokenGeoBlock",
+            "org.pfaa.geologica.block.BrickGeoBlock",
     })
     public static String[] blockCrackFixRenderPassWhitelist__;
 
@@ -217,8 +228,31 @@ public class AngelicaConfig {
     @Config.DefaultBoolean(false)
     public static boolean enableHardcodedCustomUniforms;
 
+    @Config.Comment("Define IS_IRIS in shader macros.")
+    @Config.DefaultBoolean(true)
+    public static boolean defineIsIris;
+
     @Config.Comment("Renders chunks before neighbors are ready. Improves loading at render distance edges, useful for low render distance servers.")
     @Config.DefaultBoolean(false)
     public static boolean useVanillaChunkTracking;
 
+    @Config.Comment("Disables additional F3 information added by Angelica.")
+    @Config.DefaultBoolean(false)
+    public static boolean disableF3Additions;
+
+    @Config.Comment("Replaces various FFP uploads with statically allocated VBO's.")
+    @Config.DefaultBoolean(true)
+    public static boolean replaceFFPUploads;
+
+    @Config.Comment("Pinned OpenGL version an integer (e.g. 46, 41, 33). 0 = auto-detect. [33, 46]. (Disable with disableGLVersionPinning=true)")
+    @Config.DefaultInt(0)
+    @Config.RangeInt(min = 0, max = 46)
+    @Config.RequiresMcRestart
+    public static int pinnedGLVersion;
+
+    @Config.Comment("Disable automatic GL version pinning. When true, always probes from highest on every launch.")
+    @Config.DefaultBoolean(false)
+    @Config.RequiresMcRestart
+    public static boolean disableGLVersionPinning;
+
 }

src/main/java/com/gtnewhorizons/angelica/config/FontConfig.java

@@ -70,4 +70,16 @@ public class FontConfig {
     @Config.DefaultFloat(1.5F)
     @Config.RangeFloat(min = 0.1F, max = 3F)
     public static float customFontScale;
+
+    @Config.Comment("A shadow offset multiplier applied only to the Unicode font.")
+    @Config.DefaultFloat(0.5F)
+    @Config.RangeFloat(min = 0F, max = 2F)
+    public static float fontShadowOffsetUC;
+
+    @Config.Comment({"Mods can provide Angelica with a mapping of special characters to either get replaced with " +
+        "different characters or rendered using the default Unicode font. Setting this to false disables the " +
+        "replacement, which is useful in cases where custom fonts have direct support for these special characters. ",
+        "See for additional details: https://github.com/GTNewHorizons/Angelica/issues/1239#issuecomment-3729877936"})
+    @Config.DefaultBoolean(true)
+    public static boolean enableGlyphReplacements;
 }

src/main/java/com/gtnewhorizons/angelica/debug/ChunkDebugMinimap.java

@@ -29,6 +29,7 @@ import cpw.mods.fml.common.eventhandler.SubscribeEvent;
 import lombok.Getter;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.multiplayer.ChunkProviderClient;
+import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.world.chunk.EmptyChunk;
 import net.minecraftforge.client.event.RenderGameOverlayEvent;
 import net.minecraftforge.common.MinecraftForge;
@@ -97,17 +98,18 @@ public class ChunkDebugMinimap {
         GLStateManager.enableBlend();
         GLStateManager.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);
 
-        GLStateManager.glBegin(GL11.GL_QUADS);
+        final Tessellator tess = Tessellator.instance;
+        tess.startDrawingQuads();
 
         final ChunkProviderClient chunkProvider = (ChunkProviderClient) mc.theWorld.getChunkProvider();
 
         for (int x = playerChunkX - RANGE; x < playerChunkX + RANGE; x++) {
             for (int z = playerChunkZ - RANGE; z < playerChunkZ + RANGE; z++) {
-                drawChunk(x, z, playerChunkX, playerChunkZ, manager, chunkProvider);
+                drawChunk(tess, x, z, playerChunkX, playerChunkZ, manager, chunkProvider);
             }
         }
 
-        GL11.glEnd();
+        tess.draw();
 
         // Restore GL state
         GLStateManager.enableLighting();
@@ -117,7 +119,7 @@ public class ChunkDebugMinimap {
         GLStateManager.glPopAttrib();
     }
 
-    private void drawChunk(int chunkX, int chunkZ, int playerChunkX, int playerChunkZ, AngelicaRenderSectionManager manager, ChunkProviderClient chunkProvider) {
+    private void drawChunk(Tessellator tess, int chunkX, int chunkZ, int playerChunkX, int playerChunkZ, AngelicaRenderSectionManager manager, ChunkProviderClient chunkProvider) {
         boolean initialized = false;
         float r = 0, g = 0, b = 0;
 
@@ -143,16 +145,16 @@ public class ChunkDebugMinimap {
             }
         }
 
-        GL11.glColor4f(r, g, b, 0.8f);
+        tess.setColorRGBA_F(r, g, b, 0.8f);
 
         final int xStart = chunkX - playerChunkX;
         final int zStart = chunkZ - playerChunkZ;
         final int xEnd = xStart + 1;
         final int zEnd = zStart + 1;
 
-        GLStateManager.glVertex3d(xStart, zStart, 0);
-        GLStateManager.glVertex3d(xStart, zEnd, 0);
-        GLStateManager.glVertex3d(xEnd, zEnd, 0);
-        GLStateManager.glVertex3d(xEnd, zStart, 0);
+        tess.addVertex(xStart, zStart, 0);
+        tess.addVertex(xStart, zEnd, 0);
+        tess.addVertex(xEnd, zEnd, 0);
+        tess.addVertex(xEnd, zStart, 0);
     }
 }

src/main/java/com/gtnewhorizons/angelica/debug/F3Direction.java

@@ -1,5 +1,6 @@
 package com.gtnewhorizons.angelica.debug;
 
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.ScaledResolution;
 import net.minecraft.client.renderer.Tessellator;
@@ -10,31 +11,31 @@ import org.lwjgl.opengl.GL11;
 public class F3Direction {
     public static void renderWorldDirectionsEvent(Minecraft mc, RenderGameOverlayEvent.Pre event) {
         if (mc.gameSettings.showDebugInfo && mc.gameSettings.thirdPersonView == 0) {
-            ScaledResolution scaledresolution = new ScaledResolution(mc, mc.displayWidth, mc.displayHeight);
-            int width = scaledresolution.getScaledWidth();
-            int height = scaledresolution.getScaledHeight();
+            final ScaledResolution scaledresolution = new ScaledResolution(mc, mc.displayWidth, mc.displayHeight);
+            final int width = scaledresolution.getScaledWidth();
+            final int height = scaledresolution.getScaledHeight();
 
-            GL11.glPushMatrix();
+            GLStateManager.glPushMatrix();
 
-            GL11.glTranslatef((float) (width / 2), (float) (height / 2), -90);
+            GLStateManager.glTranslatef((float) (width / 2), (float) (height / 2), -90);
 
-            Entity entity = mc.renderViewEntity;
-            GL11.glRotatef(entity.prevRotationPitch + (entity.rotationPitch - entity.prevRotationPitch) * event.partialTicks, -1.0F, 0.0F, 0.0F);
-            GL11.glRotatef(entity.prevRotationYaw + (entity.rotationYaw - entity.prevRotationYaw) * event.partialTicks, 0.0F, 1.0F, 0.0F);
+            final Entity entity = mc.renderViewEntity;
+            GLStateManager.glRotatef(entity.prevRotationPitch + (entity.rotationPitch - entity.prevRotationPitch) * event.partialTicks, -1.0F, 0.0F, 0.0F);
+            GLStateManager.glRotatef(entity.prevRotationYaw + (entity.rotationYaw - entity.prevRotationYaw) * event.partialTicks, 0.0F, 1.0F, 0.0F);
 
-            GL11.glScalef(-1.0F, -1.0F, -1.0F);
+            GLStateManager.glScalef(-1.0F, -1.0F, -1.0F);
 
             renderWorldDirections();
 
-            GL11.glPopMatrix();
+            GLStateManager.glPopMatrix();
         }
     }
     public static void renderWorldDirections() {
-        GL11.glDisable(GL11.GL_TEXTURE_2D);
-        GL11.glDepthMask(false);
-        Tessellator tessellator = Tessellator.instance;
+        GLStateManager.disableTexture();
+        GLStateManager.glDepthMask(false);
+        final Tessellator tessellator = Tessellator.instance;
 
-        GL11.glLineWidth(2.0F);
+        GLStateManager.glLineWidth(2.0F);
         tessellator.startDrawing(GL11.GL_LINES);
 
         //X
@@ -54,8 +55,8 @@ public class F3Direction {
 
         tessellator.draw();
 
-        GL11.glLineWidth(1.0F);
-        GL11.glDepthMask(true);
-        GL11.glEnable(GL11.GL_TEXTURE_2D);
+        GLStateManager.glLineWidth(1.0F);
+        GLStateManager.glDepthMask(true);
+        GLStateManager.enableTexture();
     }
 }

src/main/java/com/gtnewhorizons/angelica/debug/F3Graph.java

@@ -1,44 +1,33 @@
 package com.gtnewhorizons.angelica.debug;
 
-import static org.lwjgl.opengl.GL11.GL_ALPHA_TEST;
-import static org.lwjgl.opengl.GL11.GL_BLEND;
-import static org.lwjgl.opengl.GL11.GL_CULL_FACE;
-import static org.lwjgl.opengl.GL11.GL_DEPTH_TEST;
-import static org.lwjgl.opengl.GL11.GL_FLOAT;
-import static org.lwjgl.opengl.GL11.GL_ONE_MINUS_SRC_ALPHA;
-import static org.lwjgl.opengl.GL11.GL_SRC_ALPHA;
-import static org.lwjgl.opengl.GL11.GL_TEXTURE_2D;
-import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
-import static org.lwjgl.opengl.GL11.GL_VERTEX_ARRAY;
-import static org.lwjgl.opengl.GL11.glBlendFunc;
-import static org.lwjgl.opengl.GL11.glColor4f;
-import static org.lwjgl.opengl.GL11.glDisable;
-import static org.lwjgl.opengl.GL11.glDisableClientState;
-import static org.lwjgl.opengl.GL11.glDrawArrays;
-import static org.lwjgl.opengl.GL11.glEnable;
-import static org.lwjgl.opengl.GL11.glEnableClientState;
-import static org.lwjgl.opengl.GL15.GL_ARRAY_BUFFER;
-import static org.lwjgl.opengl.GL15.GL_STATIC_DRAW;
-import static org.lwjgl.opengl.GL15.glBindBuffer;
-import static org.lwjgl.opengl.GL15.glBufferData;
-import static org.lwjgl.opengl.GL15.glGenBuffers;
-import static org.lwjgl.opengl.GL20.glDisableVertexAttribArray;
-import static org.lwjgl.opengl.GL20.glEnableVertexAttribArray;
-import static org.lwjgl.opengl.GL20.glUniform1;
-import static org.lwjgl.opengl.GL20.glUniform1f;
-import static org.lwjgl.opengl.GL20.glUniform1i;
-import static org.lwjgl.opengl.GL20.glVertexAttribPointer;
-import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryStack.*;
-
 import com.gtnewhorizon.gtnhlib.bytebuf.MemoryStack;
 import com.gtnewhorizon.gtnhlib.client.renderer.shader.ShaderProgram;
-import java.nio.FloatBuffer;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.FontRenderer;
 import net.minecraft.client.gui.ScaledResolution;
 import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.util.ResourceLocation;
 import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.GL30;
+
+import java.nio.FloatBuffer;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryStack.stackPush;
+import static com.gtnewhorizons.angelica.glsm.GLStateManager.glBindBuffer;
+import static org.lwjgl.opengl.GL11.GL_FLOAT;
+import static org.lwjgl.opengl.GL11.GL_ONE_MINUS_SRC_ALPHA;
+import static org.lwjgl.opengl.GL11.GL_SRC_ALPHA;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
+import static org.lwjgl.opengl.GL15.GL_ARRAY_BUFFER;
+import static org.lwjgl.opengl.GL15.GL_STATIC_DRAW;
+import static org.lwjgl.opengl.GL15.glBufferData;
+import static org.lwjgl.opengl.GL15.glGenBuffers;
+import static org.lwjgl.opengl.GL20.glEnableVertexAttribArray;
+import static org.lwjgl.opengl.GL20.glUniform1;
+import static org.lwjgl.opengl.GL20.glUniform1f;
+import static org.lwjgl.opengl.GL20.glUniform1i;
+import static org.lwjgl.opengl.GL20.glVertexAttribPointer;
 
 public abstract class F3Graph {
     private static final int NUM_SAMPLES = 240;
@@ -63,6 +52,7 @@ public abstract class F3Graph {
     private int uHeadIdx;
     private int uSamples;
     private int vertBuf;
+    private int vao;
     private final ResourceLocation texture;
     private final float pxPerNs;
     private final boolean left;
@@ -117,8 +107,8 @@ public abstract class F3Graph {
             "shaders/debug_graph.frag.glsl");
         shader.use();
 
-        // Register attributes
-        aPos = shader.getAttribLocation("pos");
+        // Attribute location is declared in shader via layout(location = 0)
+        aPos = 0;
 
         // Register uniforms
         uFBWidth = shader.getUniformLocation("fbWidth");
@@ -129,7 +119,9 @@ public abstract class F3Graph {
         final int uPxPerNs = shader.getUniformLocation("pxPerNs");
         final int uLeft = shader.getUniformLocation("left");
 
-        // Load vertex buffer
+        vao = GL30.glGenVertexArrays();
+        GLStateManager.glBindVertexArray(vao);
+
         vertBuf = glGenBuffers();
         glBindBuffer(GL_ARRAY_BUFFER, vertBuf);
         try (final MemoryStack stack = stackPush()) {
@@ -146,7 +138,13 @@ public abstract class F3Graph {
 
             glBufferData(GL_ARRAY_BUFFER, vertices, GL_STATIC_DRAW);
         }
+
+        // Configure vertex attribute in the VAO
+        glVertexAttribPointer(aPos, VERT_FLOATS, GL_FLOAT, false, VERT_FLOATS * 4, 0);
+        glEnableVertexAttribArray(aPos);
+
         glBindBuffer(GL_ARRAY_BUFFER, 0);
+        GLStateManager.glBindVertexArray(0);
 
         final Minecraft mc = Minecraft.getMinecraft();
         final ScaledResolution sr = new ScaledResolution(mc, mc.displayWidth, mc.displayHeight);
@@ -186,21 +184,21 @@ public abstract class F3Graph {
 
         // Setup GL state
         final Tessellator tess = Tessellator.instance;
-        glDisable(GL_DEPTH_TEST);
-        glEnable(GL_ALPHA_TEST);
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+        GLStateManager.disableDepthTest();
+        GLStateManager.enableAlphaTest();
+        GLStateManager.enableBlend();
+        GLStateManager.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
         // Draw background
-        glDisable(GL_TEXTURE_2D);
-        glColor4f(0x50 / 255.0F, 0x50 / 255.0F, 0x50 / 255.0F, 0x90 / 255.0F);
+        GLStateManager.disableTexture();
+        GLStateManager.glColor4f(0x50 / 255.0F, 0x50 / 255.0F, 0x50 / 255.0F, 0x90 / 255.0F);
         tess.startDrawingQuads();
         for (int i = 0; i < 4; ++i) {
             tess.addVertex(getVertX(sr, i), getVertY(sr, i), 0);
         }
         tess.draw();
-        glColor4f(1.0F, 1.0F, 1.0F, 1.0F);
-        glEnable(GL_TEXTURE_2D);
+        GLStateManager.glColor4f(1.0F, 1.0F, 1.0F, 1.0F);
+        GLStateManager.enableTexture();
 
 
         // Draw samples
@@ -213,21 +211,16 @@ public abstract class F3Graph {
         glUniform1i(uHeadIdx, samplesHead);
         glUniform1(uSamples, sampleBuf);
 
-        glBindBuffer(GL_ARRAY_BUFFER, vertBuf);
-        glEnableVertexAttribArray(aPos);
-        glVertexAttribPointer(aPos, VERT_FLOATS, GL_FLOAT, false, VERT_FLOATS * 4, 0);
-        glEnableClientState(GL_VERTEX_ARRAY);
+        GLStateManager.glBindVertexArray(vao);
 
         // Left side graphs are inverted, so temporarily disable culling
-        if (!left) glDisable(GL_CULL_FACE);
+        if (!left) GLStateManager.disableCull();
 
-        glDrawArrays(GL_TRIANGLE_STRIP, 0, VERT_COUNT);
+        GLStateManager.glDrawArrays(GL_TRIANGLE_STRIP, 0, VERT_COUNT);
 
-        if (!left) glEnable(GL_CULL_FACE);
+        if (!left) GLStateManager.enableCull();
 
-        glDisableClientState(GL_VERTEX_ARRAY);
-        glDisableVertexAttribArray(aPos);
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        GLStateManager.glBindVertexArray(0);
 
         ShaderProgram.clear();
 
@@ -242,9 +235,9 @@ public abstract class F3Graph {
         tess.draw();
 
         // Reset GL state
-        glEnable(GL_DEPTH_TEST);
-        glDisable(GL_ALPHA_TEST);
-        glDisable(GL_BLEND);
+        GLStateManager.enableDepthTest();
+        GLStateManager.disableAlphaTest();
+        GLStateManager.disableBlend();
 
         // Draw text
         // Ensure running counters are reset on first sample

src/main/java/com/gtnewhorizons/angelica/dynamiclights/DynamicLights.java

@@ -6,6 +6,7 @@ import com.gtnewhorizon.gtnhlib.blockpos.IBlockPos;
 import com.gtnewhorizon.gtnhlib.util.CoordinatePacker;
 import com.gtnewhorizons.angelica.api.IDynamicLightProducer;
 import com.gtnewhorizons.angelica.compat.ModStatus;
+import com.gtnewhorizons.angelica.compat.backhand.BackhandReflectionCompat;
 import com.gtnewhorizons.angelica.compat.battlegear2.Battlegear2Compat;
 import com.gtnewhorizons.angelica.config.AngelicaConfig;
 import com.gtnewhorizons.angelica.dynamiclights.config.EntityLightConfig;
@@ -52,6 +53,7 @@ public class DynamicLights {
     private static final double MAX_RADIUS_SQUARED = MAX_RADIUS * MAX_RADIUS;
     private final Set<IDynamicLightSource> dynamicLightSources = new ObjectOpenHashSet<>();
     private final ReentrantReadWriteLock lightSourcesLock = new ReentrantReadWriteLock();
+    private volatile int lightSourceCount = 0;
     private final ChunkRebuildManager chunkRebuildManager = new ChunkRebuildManager();
     private long lastUpdate = System.currentTimeMillis();
     private int lastUpdateCount = 0;
@@ -70,6 +72,10 @@ public class DynamicLights {
             (ShaderForce || !IrisApi.getInstance().isShaderPackInUse());
     }
 
+    public boolean hasLightSources() {
+        return lightSourceCount > 0;
+    }
+
     public static IDynamicLightWorldRenderer getActiveRenderer() {
         return activeRenderer;
     }
@@ -142,7 +148,9 @@ public class DynamicLights {
 
     public void addLightSource(IDynamicLightSource lightSource) {
         this.lightSourcesLock.writeLock().lock();
-        this.dynamicLightSources.add(lightSource);
+        if (this.dynamicLightSources.add(lightSource)) {
+            this.lightSourceCount = this.dynamicLightSources.size();
+        }
         this.lightSourcesLock.writeLock().unlock();
     }
 
@@ -160,6 +168,7 @@ public class DynamicLights {
             it = dynamicLightSources.next();
             if (it.equals(lightSource)) {
                 dynamicLightSources.remove();
+                this.lightSourceCount = this.dynamicLightSources.size();
                 if (activeRenderer != null)
                     lightSource.angelica$scheduleTrackedChunksRebuild(activeRenderer);
                 break;
@@ -183,6 +192,7 @@ public class DynamicLights {
             it = dynamicLightSources.next();
             if (filter.test(it)) {
                 dynamicLightSources.remove();
+                this.lightSourceCount = this.dynamicLightSources.size();
                 if (activeRenderer != null) {
                     if (it.angelica$getLuminance() > 0)
                         it.angelica$resetDynamicLight();
@@ -212,6 +222,7 @@ public class DynamicLights {
                 it.angelica$scheduleTrackedChunksRebuild(activeRenderer);
             }
         }
+        this.lightSourceCount = 0;
 
         this.lightSourcesLock.writeLock().unlock();
     }
@@ -542,7 +553,7 @@ public class DynamicLights {
                     }
                 }
                 else if (ModStatus.isBackhandLoaded){
-                    ItemStack offhand = ModStatus.backhandCompat.getOffhandItem(player);
+                    ItemStack offhand = BackhandReflectionCompat.getOffhandItem(player);
                     if (offhand != null) {
                         luminance = Math.max(luminance, getLuminanceFromItemStack(offhand));
                     }

src/main/java/com/gtnewhorizons/angelica/glsm/AngelicaGLStateManagerService.java

@@ -1,5 +1,6 @@
 package com.gtnewhorizons.angelica.glsm;
 
+import com.gtnewhorizon.gtnhlib.client.opengl.UniversalVAO;
 import com.mitchej123.glsm.GLStateManagerService;
 import org.lwjgl.BufferUtils;
 import org.lwjgl.opengl.GL11;
@@ -149,17 +150,17 @@ public class AngelicaGLStateManagerService implements GLStateManagerService {
 
     @Override
     public int glGenVertexArrays() {
-        return GL30.glGenVertexArrays();
+        return UniversalVAO.genVertexArrays();
     }
 
     @Override
     public void glBindVertexArray(int array) {
-        GL30.glBindVertexArray(array);
+        GLStateManager.glBindVertexArray(array);
     }
 
     @Override
     public void glDeleteVertexArrays(int array) {
-        GL30.glDeleteVertexArrays(array);
+        GLStateManager.glDeleteVertexArrays(array);
     }
 
     // ===================== BUFFER OPERATIONS =====================
@@ -171,12 +172,12 @@ public class AngelicaGLStateManagerService implements GLStateManagerService {
 
     @Override
     public void glBindBuffer(int target, int buffer) {
-        GL15.glBindBuffer(target, buffer);
+        GLStateManager.glBindBuffer(target, buffer);
     }
 
     @Override
     public void glDeleteBuffers(int buffer) {
-        GL15.glDeleteBuffers(buffer);
+        GLStateManager.glDeleteBuffers(buffer);
     }
 
     // ===================== TEXTURE OPERATIONS =====================
@@ -188,7 +189,7 @@ public class AngelicaGLStateManagerService implements GLStateManagerService {
 
     @Override
     public void glGenTextures(int[] textures) {
-        IntBuffer buffer = getIntArrayBuffer(textures.length);
+        final IntBuffer buffer = getIntArrayBuffer(textures.length);
         GL11.glGenTextures(buffer);
         buffer.get(textures);
     }
@@ -200,7 +201,7 @@ public class AngelicaGLStateManagerService implements GLStateManagerService {
 
     @Override
     public void glDeleteTextures(int[] textures) {
-        IntBuffer buffer = getIntArrayBuffer(textures.length);
+        final IntBuffer buffer = getIntArrayBuffer(textures.length);
         buffer.put(textures);
         buffer.flip();
         GLStateManager.glDeleteTextures(buffer);
@@ -352,7 +353,7 @@ public class AngelicaGLStateManagerService implements GLStateManagerService {
 
     @Override
     public void setBoundTexture(int unit, int texture) {
-        int currentUnit = GLStateManager.getActiveTextureUnit();
+        final int currentUnit = GLStateManager.getActiveTextureUnit();
         if (currentUnit != unit) {
             GLStateManager.glActiveTexture(GL13.GL_TEXTURE0 + unit);
         }

src/main/java/com/gtnewhorizons/angelica/glsm/CommandBufferBuilder.java

@@ -1,238 +1,67 @@
 package com.gtnewhorizons.angelica.glsm;
 
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
+import com.gtnewhorizons.angelica.glsm.recording.AccumulatedDraw;
 import com.gtnewhorizons.angelica.glsm.recording.CommandBuffer;
 import com.gtnewhorizons.angelica.glsm.recording.CommandBufferProcessor;
-import com.gtnewhorizons.angelica.glsm.recording.CommandBufferProcessor.BufferTransformOptimizer;
-import it.unimi.dsi.fastutil.objects.Object2IntMap;
-import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 
-import java.util.ArrayList;
-import java.util.Comparator;
 import java.util.List;
-import java.util.Map;
 
 /**
  * Builds final command buffers from raw command buffers and compiled VBO data.
- * Transforms are already collapsed to MultMatrix during recording; the optimizer
- * tracks transform state to emit deltas when draws need a different transform.
+ * Bridges the gap between VBO compilation (glsm types) and buffer processing (recording types).
  */
 public final class CommandBufferBuilder {
 
-    private static final Logger LOGGER = LogManager.getLogger("CommandBufferBuilder");
-
     private CommandBufferBuilder() {}
 
-    /** Build with transform delta optimization and merged draw ranges. */
-    public static void buildOptimizedFromRawBuffer(
+    /**
+     * Build commands with transform collapsing optimization.
+     * Accumulates MODELVIEW transforms and emits MultMatrix at barriers (draws, CallList).
+     * Uses mergedRanges where consecutive same-transform draws are combined.
+     */
+    public static void buildFromRawBuffer(
             CommandBuffer rawBuffer,
-            Map<CapturingTessellator.Flags, CompiledFormatBuffer> compiledQuadBuffers,
-            final CompiledLineBuffer compiledLineBuffer,
-            final Map<CapturingTessellator.Flags, CompiledPrimitiveBuffers> compiledPrimitiveBuffers,
-            VertexBuffer[] ownedVbos,
-            int glListId,
+            List<AccumulatedDraw> accumulatedDraws,
             CommandBuffer finalBuffer) {
 
-        // Build VBO index map for efficient lookup (no boxing)
-        final Object2IntMap<VertexBuffer> vboIndexMap = new Object2IntOpenHashMap<>();
-        vboIndexMap.defaultReturnValue(-1);
-        for (int i = 0; i < ownedVbos.length; i++) {
-            vboIndexMap.put(ownedVbos[i], i);
-        }
-
-        // Collect all merged draw ranges sorted by command index
-        final List<DrawRangeWithBuffer> allRanges = collectDrawRanges(compiledQuadBuffers, compiledLineBuffer, compiledPrimitiveBuffers);
-
-        // Buffer optimizer state
-        final BufferTransformOptimizer opt = new BufferTransformOptimizer();
-
         rawBuffer.resetRead();
         int cmdIndex = 0;
         int rangeIndex = 0;
 
+        AccumulatedDraw draw;
         while (rawBuffer.hasRemaining()) {
-            // Emit draw ranges at this command position
-            while (rangeIndex < allRanges.size() && allRanges.get(rangeIndex).range().commandIndex() == cmdIndex) {
-                emitDrawRangeToBuffer(allRanges.get(rangeIndex++), opt, finalBuffer, vboIndexMap);
-            }
-
             // Read and process the command
-            final int opcode = rawBuffer.readInt();
-            CommandBufferProcessor.processCommandForOptimization(opcode, rawBuffer, opt, finalBuffer);
-            cmdIndex++;
-        }
-
-        // Emit remaining draw ranges at end of command stream
-        while (rangeIndex < allRanges.size()) {
-            emitDrawRangeToBuffer(allRanges.get(rangeIndex++), opt, finalBuffer, vboIndexMap);
-        }
-
-        // Emit residual transform if not identity
-        if (!opt.isIdentity()) {
-            opt.emitPendingTransform(finalBuffer);
-        }
-    }
-
-    /** Debug build: no optimizations, 1:1 draw commands. */
-    public static void buildUnoptimizedFromRawBuffer(
-            CommandBuffer rawBuffer,
-            Map<CapturingTessellator.Flags, CompiledFormatBuffer> compiledQuadBuffers,
-            CompiledLineBuffer compiledLineBuffer,
-            Map<CapturingTessellator.Flags, CompiledPrimitiveBuffers> compiledPrimitiveBuffers,
-            VertexBuffer[] ownedVbos,
-            CommandBuffer finalBuffer) {
-
-        // Build VBO index map for efficient lookup (no boxing)
-        final Object2IntMap<VertexBuffer> vboIndexMap = new Object2IntOpenHashMap<>();
-        vboIndexMap.defaultReturnValue(-1);
-        for (int i = 0; i < ownedVbos.length; i++) {
-            vboIndexMap.put(ownedVbos[i], i);
-        }
-
-        // Collect per-draw ranges (no merging) sorted by command index
-        final List<DrawRangeWithBuffer> allRanges = collectDrawRangesUnoptimized(compiledQuadBuffers, compiledLineBuffer, compiledPrimitiveBuffers);
-
-        rawBuffer.resetRead();
-        int cmdIndex = 0;
-        int rangeIndex = 0;
-
-        while (rawBuffer.hasRemaining()) {
-            // Emit draw ranges at this command position
-            while (rangeIndex < allRanges.size() && allRanges.get(rangeIndex).range().commandIndex() == cmdIndex) {
-                final DrawRangeWithBuffer drb = allRanges.get(rangeIndex++);
-                final int vboIdx = vboIndexMap.getInt(drb.vbo());
-                if (vboIdx >= 0) {
-                    finalBuffer.writeDrawRange(vboIdx, drb.range().startVertex(), drb.range().vertexCount(), drb.hasBrightness());
-                    DisplayListManager.trackDrawRangeSource(drb.source().toString());
-                }
-            }
-
-            // Copy the command directly
             CommandBufferProcessor.copyCommand(rawBuffer, finalBuffer);
+
+            // Emit draw ranges at this command position
+            while (rangeIndex < accumulatedDraws.size() && (draw = accumulatedDraws.get(rangeIndex)).commandIndex == cmdIndex) {
+                emitDrawRangeToBuffer(draw, finalBuffer, rangeIndex);
+                rangeIndex++;
+            }
+
             cmdIndex++;
         }
 
-        // Emit remaining draw ranges at end of command stream
-        while (rangeIndex < allRanges.size()) {
-            final DrawRangeWithBuffer drb = allRanges.get(rangeIndex++);
-            final int vboIdx = vboIndexMap.getInt(drb.vbo());
-            if (vboIdx >= 0) {
-                finalBuffer.writeDrawRange(vboIdx, drb.range().startVertex(), drb.range().vertexCount(), drb.hasBrightness());
-                DisplayListManager.trackDrawRangeSource(drb.source().toString());
-            }
+        while (rangeIndex < accumulatedDraws.size()) {
+            emitDrawRangeToBuffer(accumulatedDraws.get(rangeIndex), finalBuffer, rangeIndex);
+            rangeIndex++;
         }
     }
 
-    /** Collect merged draw ranges, sorted by command index. */
-    static List<DrawRangeWithBuffer> collectDrawRanges(
-            Map<CapturingTessellator.Flags, CompiledFormatBuffer> compiledQuadBuffers,
-            CompiledLineBuffer compiledLineBuffer,
-            Map<CapturingTessellator.Flags, CompiledPrimitiveBuffers> compiledPrimitiveBuffers) {
-        return collectDrawRangesInternal(compiledQuadBuffers, compiledLineBuffer, compiledPrimitiveBuffers, true);
-    }
-
-    /** Collect unmerged draw ranges for debug mode. */
-    static List<DrawRangeWithBuffer> collectDrawRangesUnoptimized(
-            Map<CapturingTessellator.Flags, CompiledFormatBuffer> compiledQuadBuffers,
-            CompiledLineBuffer compiledLineBuffer,
-            Map<CapturingTessellator.Flags, CompiledPrimitiveBuffers> compiledPrimitiveBuffers) {
-        return collectDrawRangesInternal(compiledQuadBuffers, compiledLineBuffer, compiledPrimitiveBuffers, false);
-    }
-
-    private static List<DrawRangeWithBuffer> collectDrawRangesInternal(
-            Map<CapturingTessellator.Flags, CompiledFormatBuffer> compiledQuadBuffers,
-            CompiledLineBuffer compiledLineBuffer,
-            Map<CapturingTessellator.Flags, CompiledPrimitiveBuffers> compiledPrimitiveBuffers,
-            boolean useMerged) {
-
-        final List<DrawRangeWithBuffer> allRanges = new ArrayList<>();
-
-        // Add quad ranges
-        final CompiledFormatBuffer[] quadBufferArray = compiledQuadBuffers.values().toArray(new CompiledFormatBuffer[0]);
-        for (int b = 0; b < quadBufferArray.length; b++) {
-            final CompiledFormatBuffer compiledBuffer = quadBufferArray[b];
-            final DrawRange[] ranges = useMerged ? compiledBuffer.mergedRanges() : compiledBuffer.perDrawRanges();
-            for (int i = 0; i < ranges.length; i++) {
-                allRanges.add(new DrawRangeWithBuffer(ranges[i], compiledBuffer.vbo(), compiledBuffer.flags(),
-                    DrawRangeWithBuffer.DrawSource.TESSELLATOR_QUADS));
-            }
-        }
-
-        // Add immediate mode line ranges
-        // Lines use a minimal flags (color only, no texture/brightness/normals)
-        if (compiledLineBuffer != null) {
-            final CapturingTessellator.Flags lineFlags = new CapturingTessellator.Flags(false, false, true, false);
-            final DrawRange[] ranges = useMerged ? compiledLineBuffer.mergedRanges() : compiledLineBuffer.perDrawRanges();
-            for (int i = 0; i < ranges.length; i++) {
-                allRanges.add(new DrawRangeWithBuffer(ranges[i], compiledLineBuffer.vbo(), lineFlags,
-                    DrawRangeWithBuffer.DrawSource.IMMEDIATE_MODE_LINES));
-            }
-        }
-
-        // Add tessellator primitive ranges (lines and triangles) - grouped by format
-        if (compiledPrimitiveBuffers != null && !compiledPrimitiveBuffers.isEmpty()) {
-            final CompiledPrimitiveBuffers[] primBufferArray = compiledPrimitiveBuffers.values().toArray(new CompiledPrimitiveBuffers[0]);
-            for (int p = 0; p < primBufferArray.length; p++) {
-                final CompiledPrimitiveBuffers primBuffers = primBufferArray[p];
-                final CapturingTessellator.Flags primFlags = primBuffers.flags();
-                // Tessellator lines
-                if (primBuffers.hasLines()) {
-                    final DrawRange[] ranges = useMerged ? primBuffers.lineMergedRanges() : primBuffers.linePerDrawRanges();
-                    final VertexBuffer vbo = primBuffers.lineVbo();
-                    for (int i = 0; i < ranges.length; i++) {
-                        allRanges.add(new DrawRangeWithBuffer(ranges[i], vbo, primFlags,
-                            DrawRangeWithBuffer.DrawSource.TESSELLATOR_LINES));
-                    }
-                }
-                // Tessellator triangles
-                if (primBuffers.hasTriangles()) {
-                    final DrawRange[] ranges = useMerged ? primBuffers.triangleMergedRanges() : primBuffers.trianglePerDrawRanges();
-                    final VertexBuffer vbo = primBuffers.triangleVbo();
-                    for (int i = 0; i < ranges.length; i++) {
-                        allRanges.add(new DrawRangeWithBuffer(ranges[i], vbo, primFlags,
-                            DrawRangeWithBuffer.DrawSource.TESSELLATOR_TRIANGLES));
-                    }
-                }
-            }
-        }
-
-        allRanges.sort(Comparator.comparingInt(r -> r.range().commandIndex()));
-        return allRanges;
-    }
-
-    /** Emit draw range with delta transform. Uses writeDrawRangeRestore for immediate mode. */
+    /**
+     * Emit a draw range to the output buffer, with transform if needed.
+     */
     private static void emitDrawRangeToBuffer(
-            DrawRangeWithBuffer drb,
-            BufferTransformOptimizer opt,
+            AccumulatedDraw draw,
             CommandBuffer out,
-            Object2IntMap<VertexBuffer> vboIndexMap) {
+            int vboIdx) {
 
-        // Emit transform to reach the draw's expected transform
-        opt.emitTransformTo(out, drb.range().transform());
+        if (draw.restoreData != null) {
+            out.writeDrawRangeRestore(vboIdx, draw.restoreData);
+            return;
+        }
 
         // Write the draw range command
-        final int vboIdx = vboIndexMap.getInt(drb.vbo());
-        if (vboIdx >= 0) {
-            final var restoreData = drb.range().restoreData();
-            if (restoreData != null) {
-                // Immediate mode draw with attribute restoration
-                final var flags = drb.flags();
-                out.writeDrawRangeRestore(
-                    vboIdx, drb.range().startVertex(), drb.range().vertexCount(),
-                    drb.hasBrightness(), flags.hasColor, flags.hasNormals, flags.hasTexture,
-                    restoreData.lastColorR(), restoreData.lastColorG(),
-                    restoreData.lastColorB(), restoreData.lastColorA(),
-                    restoreData.lastNormalX(), restoreData.lastNormalY(), restoreData.lastNormalZ(),
-                    restoreData.lastTexCoordS(), restoreData.lastTexCoordT()
-                );
-            } else {
-                // Regular tessellator draw (no restoration needed)
-                out.writeDrawRange(vboIdx, drb.range().startVertex(), drb.range().vertexCount(), drb.hasBrightness());
-            }
-            DisplayListManager.trackDrawRangeSource(drb.source().toString());
-        }
+        out.writeDrawRange(vboIdx);
     }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/CompatShaderTransformer.java

@@ -0,0 +1,460 @@
+package com.gtnewhorizons.angelica.glsm;
+
+import net.minecraft.launchwrapper.Launch;
+import org.taumc.glsl.ShaderParser;
+import org.taumc.glsl.Transformer;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import static com.gtnewhorizons.angelica.loading.AngelicaTweaker.LOGGER;
+
+/**
+ * Compat transformation for mod shaders running under core profile.
+ *
+ * <p>Handles:
+ * <ul>
+ *   <li>Matrix builtin replacement (gl_ModelViewMatrix, gl_ProjectionMatrix, etc.)</li>
+ *   <li>Vertex attribute replacement (gl_Vertex, gl_Color, gl_MultiTexCoord0/1, gl_Normal)</li>
+ *   <li>gl_TexCoord[N] varying array → per-index in/out declarations</li>
+ *   <li>Texture function renames (texture2D → texture, etc.)</li>
+ *   <li>Fragment output handling (gl_FragColor → layout-qualified out declarations)</li>
+ *   <li>Fog builtins (gl_Fog, gl_FogFragCoord)</li>
+ *   <li>gl_FrontColor → local variable in vertex shaders</li>
+ *   <li>shadow2D/shadow2DLod → texture/textureLod with vec4 wrapping</li>
+ *   <li>Version upgrade to 330 core minimum</li>
+ *   <li>Reserved word pre-parse renaming (texture-as-variable, sample, etc.)</li>
+ * </ul>
+ */
+public class CompatShaderTransformer {
+
+    private static final Pattern VERSION_PATTERN =
+        Pattern.compile("#version[ \\t]+(\\d+)(?:[ \\t]+(\\w+))?");
+
+    private static final Pattern DEFINE_PATTERN =
+        Pattern.compile("^\\s*#\\s*define\\s+.+$", Pattern.MULTILINE);
+
+    /** Compat builtins that trigger AST transformation.  */
+    private static final Set<String> COMPAT_BUILTINS = Set.of(
+        "gl_ModelView", "gl_Projection", "gl_NormalMatrix", "gl_TextureMatrix",
+        "gl_FragColor", "gl_Fog", "gl_FrontColor", "gl_Color",
+        "gl_Vertex", "gl_MultiTexCoord", "gl_TexCoord", "gl_Normal", "ftransform",
+        "texture2D", "texture3D", "texelFetch2D", "texelFetch3D", "textureSize2D",
+        "shadow2D", "gl_FrontLightModelProduct",
+        "gl_LightSource", "gl_FrontMaterial"
+    );
+
+    private static final Pattern NEEDS_TRANSFORM_PATTERN = Pattern.compile(
+        String.join("|", COMPAT_BUILTINS) + "|\\b(?:attribute|varying)\\b"
+    );
+
+    private static final Map<String, String> MATRIX_RENAMES = Map.of(
+        "gl_ModelViewMatrix", "angelica_ModelViewMatrix",
+        "gl_ModelViewMatrixInverse", "angelica_ModelViewMatrixInverse",
+        "gl_ProjectionMatrix", "angelica_ProjectionMatrix",
+        "gl_ProjectionMatrixInverse", "angelica_ProjectionMatrixInverse",
+        "gl_NormalMatrix", "angelica_NormalMatrix"
+    );
+
+    private static final Path DUMP_DIR;
+    private static final AtomicInteger dumpCounter = new AtomicInteger(0);
+    static {
+        boolean isDev = false;
+        try {
+            final Object deobfEnv = Launch.blackboard != null ? Launch.blackboard.get("fml.deobfuscatedEnvironment") : null;
+            isDev = Boolean.TRUE.equals(deobfEnv);
+        } catch (Exception ignored) {}
+        DUMP_DIR = (isDev || Boolean.parseBoolean(System.getProperty("angelica.compat.dumpShaders", "false")))
+            ? Paths.get("compat_shaders") : null;
+    }
+
+    private static final int CACHE_SIZE = 32;
+    private record CacheKey(String source, boolean isFragment) {}
+    private static final Map<CacheKey, String> cache = Collections.synchronizedMap(
+        new LinkedHashMap<>(32, 0.75f, true) {
+            @Override protected boolean removeEldestEntry(Map.Entry<CacheKey, String> eldest) {
+                return size() > CACHE_SIZE;
+            }
+        });
+
+    public static void clearCache() {
+        cache.clear();
+    }
+
+    /**
+     * Transform a mod shader source for core profile compatibility.
+     */
+    public static String transform(String source, boolean isFragment) {
+        final boolean needsTransform = needsTransformation(source);
+        String result;
+        if (!needsTransform) {
+            result = fixupVersion(source);
+        } else {
+            final CacheKey key = new CacheKey(source, isFragment);
+            final String cached = cache.get(key);
+            if (cached != null) {
+                dumpShader(source, cached, isFragment, needsTransform);
+                return cached;
+            }
+
+            try {
+                result = transformInternal(source, isFragment);
+                cache.put(key, result);
+            } catch (Exception e) {
+                LOGGER.warn("CompatShaderTransformer: AST transformation failed, falling back to version fixup only", e);
+                result = fixupVersion(source);
+            }
+        }
+
+        dumpShader(source, result, isFragment, needsTransform);
+        return result;
+    }
+
+    private static boolean needsTransformation(String source) {
+        // Shaders already at 330+ core don't need compat transformation
+        final Matcher vm = VERSION_PATTERN.matcher(source);
+        if (vm.find()) {
+            final int version = Integer.parseInt(vm.group(1));
+            if (version >= 330 && "core".equals(vm.group(2))) return false;
+        }
+
+        return NEEDS_TRANSFORM_PATTERN.matcher(source).find();
+    }
+
+    private static String transformInternal(String source, boolean isFragment) {
+        final Matcher versionMatcher = VERSION_PATTERN.matcher(source);
+        int declaredVersion = 110;
+        if (versionMatcher.find()) {
+            declaredVersion = Integer.parseInt(versionMatcher.group(1));
+        }
+
+        final int targetVersion = Math.max(declaredVersion, 330);
+
+        // Pre-parse reserved word renaming — prevents ANTLR parse failures
+        source = GlslTransformUtils.replaceTexture(source);
+        source = GlslTransformUtils.renameReservedWords(source, targetVersion);
+
+        final ShaderParser.ParsedShader parsedShader = ShaderParser.parseShader(source);
+        final Transformer transformer = new Transformer(parsedShader.full());
+
+        injectMatrixUniforms(transformer);
+
+        transformFog(transformer, isFragment, source);
+
+        // gl_FrontLightModelProduct.sceneColor → angelica_SceneColor uniform
+        if (source.contains("gl_FrontLightModelProduct")) {
+            transformer.injectVariable("uniform vec4 angelica_SceneColor;");
+            transformer.replaceExpression("gl_FrontLightModelProduct.sceneColor", "angelica_SceneColor");
+        }
+
+        // gl_LightSource[i] → struct + uniform array (both via injectFunction to keep struct before uniform)
+        if (source.contains("gl_LightSource")) {
+            transformer.injectFunction(
+                "struct angelica_LightSourceParameters {"
+                + "vec4 ambient;vec4 diffuse;vec4 specular;vec4 position;vec4 halfVector;"
+                + "vec3 spotDirection;float spotExponent;float spotCutoff;float spotCosCutoff;"
+                + "float constantAttenuation;float linearAttenuation;float quadraticAttenuation;"
+                + "};");
+            transformer.injectFunction("uniform angelica_LightSourceParameters angelica_LightSource[2];");
+            transformer.rename("gl_LightSource", "angelica_LightSource");
+        }
+
+        // gl_FrontMaterial → struct + uniform (both via injectFunction to keep struct before uniform)
+        if (source.contains("gl_FrontMaterial")) {
+            transformer.injectFunction(
+                "struct angelica_MaterialParameters {"
+                + "vec4 emission;vec4 ambient;vec4 diffuse;vec4 specular;float shininess;"
+                + "};");
+            transformer.injectFunction("uniform angelica_MaterialParameters angelica_FrontMaterial;");
+            transformer.rename("gl_FrontMaterial", "angelica_FrontMaterial");
+        }
+
+        // gl_FrontColor (vertex) → gl_Color (fragment) varying chain
+        // Vertex side is unconditional: fragment may read gl_Color without vertex writing gl_FrontColor.
+        // Uses angelica_ prefix to avoid colliding with user-declared varyings (e.g. "v_Color").
+        if (!isFragment) {
+            transformer.injectVariable("out vec4 angelica_FrontColor;");
+            transformer.rename("gl_FrontColor", "angelica_FrontColor");
+            transformer.prependMain("angelica_FrontColor = vec4(1.0);");
+
+            // Vertex attributes — replaces removed FFP vertex inputs with explicit in declarations
+            transformVertexAttributes(transformer, source);
+        } else {
+            if (source.contains("gl_Color")) {
+                transformer.injectVariable("in vec4 angelica_FrontColor;");
+                transformer.rename("gl_Color", "angelica_FrontColor");
+            }
+        }
+
+        // gl_TexCoord[N] varying array → per-index in/out declarations
+        final Set<Integer> texCoordIndices = new HashSet<>();
+        transformer.renameArray("gl_TexCoord", "angelica_TexCoord", texCoordIndices);
+        for (Integer i : texCoordIndices) {
+            final String qualifier = isFragment ? "in" : "out";
+            transformer.injectVariable(qualifier + " vec4 angelica_TexCoord" + i + ";");
+        }
+
+        // Fragment output handling + alpha test discard
+        if (isFragment) {
+            transformFragmentOutputs(transformer);
+        }
+
+        // texture-as-variable collision handling
+        if (transformer.containsCall("texture") && transformer.hasVariable("texture")) {
+            transformer.rename("texture", "gtexture");
+        }
+        if (transformer.hasVariable("angelica_renamed_texture")) {
+            transformer.rename("angelica_renamed_texture", "gtexture");
+        }
+
+        transformer.renameFunctionCall(GlslTransformUtils.TEXTURE_RENAMES);
+
+        transformer.renameAndWrapShadow("shadow2D", "texture");
+        transformer.renameAndWrapShadow("shadow2DLod", "textureLod");
+
+        final String versionDirective = "#version " + targetVersion + " core\n";
+        final String extensions = VERSION_PATTERN.matcher(GlslTransformUtils.getFormattedShader(parsedShader.pre(), "")).replaceFirst("").trim();
+
+        // Preserve #define directives
+        final StringBuilder defines = new StringBuilder();
+        final Matcher defineMatcher = DEFINE_PATTERN.matcher(source);
+        while (defineMatcher.find()) {
+            defines.append(defineMatcher.group().trim()).append('\n');
+        }
+
+        final String header = versionDirective + (extensions.isEmpty() ? "" : "\n" + extensions) + (defines.isEmpty() ? "" : "\n" + defines);
+        final StringBuilder result = new StringBuilder();
+        transformer.mutateTree(tree -> result.append(GlslTransformUtils.getFormattedShader(tree, header)));
+
+        // Restore pre-parse renames
+        String output = GlslTransformUtils.restoreReservedWords(result.toString());
+
+        // Core profile: attribute → in, varying → out (vertex) / in (fragment)
+        output = fixupQualifiers(output, isFragment);
+
+        return output;
+    }
+
+    /**
+     * Inject matrix uniforms and rename compat builtins.
+     */
+    private static void injectMatrixUniforms(Transformer transformer) {
+        transformer.injectVariable("uniform mat4 angelica_ModelViewMatrix;");
+        transformer.injectVariable("uniform mat4 angelica_ModelViewMatrixInverse;");
+        transformer.injectVariable("uniform mat4 angelica_ProjectionMatrix;");
+        transformer.injectVariable("uniform mat4 angelica_ProjectionMatrixInverse;");
+        transformer.injectVariable("uniform mat3 angelica_NormalMatrix;");
+        transformer.injectVariable("uniform mat4 angelica_LightmapTextureMatrix;");
+
+        transformer.rename(MATRIX_RENAMES);
+
+        // Expression replacements
+        transformer.replaceExpression("gl_ModelViewProjectionMatrix", "(angelica_ProjectionMatrix * angelica_ModelViewMatrix)");
+        transformer.replaceExpression("gl_TextureMatrix[0]", "mat4(1.0)");
+        transformer.replaceExpression("gl_TextureMatrix[1]", "angelica_LightmapTextureMatrix");
+        transformer.replaceExpression("gl_TextureMatrix", "mat4[8](mat4(1.0), angelica_LightmapTextureMatrix, mat4(1.0), mat4(1.0), mat4(1.0), mat4(1.0), mat4(1.0), mat4(1.0))");
+    }
+
+    /**
+     * Transform fragment outputs for core profile.
+     */
+    private static void transformFragmentOutputs(Transformer transformer) {
+        if (transformer.containsCall("gl_FragColor")) {
+            transformer.replaceExpression("gl_FragColor", "gl_FragData[0]");
+        }
+
+        final Set<Integer> found = new HashSet<>();
+        transformer.renameArray("gl_FragData", "angelica_FragData", found);
+
+        for (Integer i : found) {
+            transformer.injectVariable("layout (location = " + i + ") out vec4 angelica_FragData" + i + ";");
+        }
+
+        // Core profile: GL_ALPHA_TEST is removed - inject runtime discard using GLSM-tracked alpha reference (uploaded by CompatUniformManager).
+        if (found.contains(0)) {
+            transformer.injectVariable("uniform float angelica_currentAlphaTest;");
+            transformer.appendMain("if (angelica_FragData0.a <= angelica_currentAlphaTest) discard;");
+        }
+    }
+
+    private static void transformFog(Transformer transformer, boolean isFragment, String source) {
+        // Vertex side is unconditional: fragment may read gl_FogFragCoord without vertex writing it
+        transformer.rename("gl_FogFragCoord", "angelica_FogFragCoord");
+        if (!isFragment) {
+            transformer.injectVariable("out float angelica_FogFragCoord;");
+            transformer.prependMain("angelica_FogFragCoord = 0.0;");
+        } else {
+            if (source.contains("gl_FogFragCoord")) {
+                transformer.injectVariable("in float angelica_FogFragCoord;");
+            }
+        }
+
+        transformer.rename("gl_Fog", "angelica_Fog");
+        transformer.injectVariable("uniform float angelica_FogDensity;");
+        transformer.injectVariable("uniform float angelica_FogStart;");
+        transformer.injectVariable("uniform float angelica_FogEnd;");
+        transformer.injectVariable("uniform vec4 angelica_FogColor;");
+        transformer.injectFunction("struct angelica_FogParameters {vec4 color;float density;float start;float end;float scale;};");
+        transformer.injectFunction(
+            "angelica_FogParameters angelica_Fog = angelica_FogParameters("
+            + "angelica_FogColor, angelica_FogDensity, angelica_FogStart, angelica_FogEnd, "
+            + "1.0 / (angelica_FogEnd - angelica_FogStart));");
+    }
+
+    /**
+     * Replace removed FFP vertex attributes with explicit {@code in} declarations at core profile attribute locations.
+     */
+    private static void transformVertexAttributes(Transformer transformer, String source) {
+        if (source.contains("gl_Vertex") || source.contains("ftransform")) {
+            transformer.injectVariable("layout(location = 0) in vec4 angelica_Vertex;");
+            transformer.rename("gl_Vertex", "angelica_Vertex");
+        }
+        // gl_Color in vertex shaders is the per-vertex color attribute, distinct from the fragment gl_Color (interpolated gl_FrontColor) handled above
+        if (source.contains("gl_Color")) {
+            transformer.injectVariable("layout(location = 1) in vec4 angelica_Color;");
+            transformer.rename("gl_Color", "angelica_Color");
+        }
+        if (source.contains("gl_MultiTexCoord0")) {
+            transformer.injectVariable("layout(location = 2) in vec4 angelica_MultiTexCoord0;");
+            transformer.rename("gl_MultiTexCoord0", "angelica_MultiTexCoord0");
+        }
+        if (source.contains("gl_MultiTexCoord1")) {
+            transformer.injectVariable("layout(location = 3) in vec4 angelica_MultiTexCoord1;");
+            transformer.rename("gl_MultiTexCoord1", "angelica_MultiTexCoord1");
+        }
+        if (source.contains("gl_Normal")) {
+            transformer.injectVariable("layout(location = 4) in vec3 angelica_Normal;");
+            transformer.rename("gl_Normal", "angelica_Normal");
+        }
+        if (source.contains("ftransform")) {
+            transformer.replaceExpression("ftransform()", "(angelica_ProjectionMatrix * angelica_ModelViewMatrix * angelica_Vertex)");
+        }
+    }
+
+    private static void dumpShader(String original, String transformed, boolean isFragment, boolean wasTransformed) {
+        if (DUMP_DIR == null) return;
+        final int id = dumpCounter.getAndIncrement();
+        final String suffix = isFragment ? ".frag.glsl" : ".vert.glsl";
+        try {
+            Files.createDirectories(DUMP_DIR);
+            // Capture caller info for identification
+            final String caller = identifyCaller();
+            final String header = "// Compat shader dump #" + id + " (" + (isFragment ? "fragment" : "vertex") + ")"
+                + "\n// Transformed: " + wasTransformed
+                + "\n// Caller: " + caller + "\n\n";
+            Files.writeString(DUMP_DIR.resolve(id + "_original" + suffix), header + original, StandardCharsets.UTF_8);
+            Files.writeString(DUMP_DIR.resolve(id + "_transformed" + suffix), header + transformed, StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            LOGGER.warn("Failed to dump compat shader: {}", e.getMessage());
+        }
+    }
+
+    private static String identifyCaller() {
+        for (StackTraceElement frame : Thread.currentThread().getStackTrace()) {
+            final String cls = frame.getClassName();
+            if (!cls.startsWith("com.gtnewhorizons.angelica.glsm.")
+                && !cls.startsWith("java.")
+                && !cls.equals("org.lwjgl.opengl.GL20")) {
+                return cls + "." + frame.getMethodName() + ":" + frame.getLineNumber();
+            }
+        }
+        return "unknown";
+    }
+
+    private static final Pattern ATTRIBUTE_PATTERN = Pattern.compile("\\battribute\\b");
+    private static final Pattern VARYING_PATTERN = Pattern.compile("\\bvarying\\b");
+
+    /** Replace legacy storage qualifiers removed in core profile. Safe on AST-serialized output (no comments). */
+    public static String fixupQualifiers(String source, boolean isFragment) {
+        source = ATTRIBUTE_PATTERN.matcher(source).replaceAll("in");
+        source = VARYING_PATTERN.matcher(source).replaceAll(isFragment ? "in" : "out");
+        return source;
+    }
+
+    // Patterns for parsing fragment shader in declarations to generate passthrough vertex shaders
+    private static final Pattern FRAG_IN_COLOR = Pattern.compile("\\bin\\s+vec4\\s+angelica_FrontColor\\b");
+    private static final Pattern FRAG_IN_TEXCOORD = Pattern.compile("\\bin\\s+vec4\\s+angelica_TexCoord(\\d+)\\b");
+    private static final Pattern FRAG_IN_FOGCOORD = Pattern.compile("\\bin\\s+float\\s+angelica_FogFragCoord\\b");
+
+    /**
+     * Generate a passthrough vertex shader for a fragment-only program.
+     *
+     * @param fragmentSource the transformed fragment shader source
+     * @return a complete vertex shader source string
+     */
+    public static String generatePassthroughVertexShader(String fragmentSource) {
+        final StringBuilder sb = new StringBuilder(512);
+        sb.append("#version 330 core\n\n");
+
+        // Always have position
+        sb.append("layout(location = 0) in vec4 a_Position;\n");
+
+        // Matrix uniforms for position transform
+        sb.append("uniform mat4 angelica_ModelViewMatrix;\n");
+        sb.append("uniform mat4 angelica_ProjectionMatrix;\n");
+
+        final StringBuilder varyings = new StringBuilder();
+        final StringBuilder assignments = new StringBuilder();
+        if (FRAG_IN_COLOR.matcher(fragmentSource).find()) {
+            sb.append("layout(location = 1) in vec4 a_Color;\n");
+            varyings.append("out vec4 angelica_FrontColor;\n");
+            assignments.append("  angelica_FrontColor = a_Color;\n");
+        }
+
+        final Matcher texCoordMatcher = FRAG_IN_TEXCOORD.matcher(fragmentSource);
+        final Set<Integer> texCoordIndices = new HashSet<>();
+        while (texCoordMatcher.find()) {
+            texCoordIndices.add(Integer.parseInt(texCoordMatcher.group(1)));
+        }
+        for (int i : texCoordIndices) {
+            // PRIMARY_UV=2, SECONDARY_UV=3. Only indices 0 and 1 are supported; higher indices collide at location 3.
+            final int location = i == 0 ? 2 : 3;
+            sb.append("layout(location = ").append(location).append(") in vec4 a_TexCoord").append(i).append(";\n");
+            varyings.append("out vec4 angelica_TexCoord").append(i).append(";\n");
+            assignments.append("  angelica_TexCoord").append(i).append(" = a_TexCoord").append(i).append(";\n");
+        }
+
+        if (FRAG_IN_FOGCOORD.matcher(fragmentSource).find()) {
+            varyings.append("out float angelica_FogFragCoord;\n");
+            assignments.append("  angelica_FogFragCoord = abs((angelica_ModelViewMatrix * a_Position).z);\n");
+        }
+
+        sb.append(varyings);
+        sb.append("\nvoid main() {\n");
+        sb.append("  gl_Position = angelica_ProjectionMatrix * angelica_ModelViewMatrix * a_Position;\n");
+        sb.append(assignments);
+        sb.append("}\n");
+
+        return sb.toString();
+    }
+
+    /** Ensure #version is at least 330 core, strip 'compatibility' profile. */
+    private static String fixupVersion(String source) {
+        final Matcher m = VERSION_PATTERN.matcher(source);
+        if (!m.find()) {
+            return "#version 330 core\n" + source;
+        }
+
+        final int version = Integer.parseInt(m.group(1));
+        final String profile = m.group(2);
+
+        if (version >= 330 && !"compatibility".equals(profile)) {
+            if ("core".equals(profile)) return source;
+            return m.replaceFirst("#version " + version + " core");
+        }
+
+        final int targetVersion = Math.max(version, 330);
+        return m.replaceFirst("#version " + targetVersion + " core");
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/CompatUniformManager.java

@@ -0,0 +1,411 @@
+package com.gtnewhorizons.angelica.glsm;
+
+import com.gtnewhorizons.angelica.glsm.stacks.FogStateStack;
+import com.gtnewhorizons.angelica.glsm.stacks.LightStateStack;
+import com.gtnewhorizons.angelica.glsm.states.ClipPlaneState;
+import com.gtnewhorizons.angelica.glsm.states.LightModelState;
+import com.gtnewhorizons.angelica.glsm.states.LightState;
+import com.gtnewhorizons.angelica.glsm.states.MaterialState;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
+import org.joml.Matrix3f;
+import org.joml.Matrix4f;
+import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL20;
+
+import java.nio.FloatBuffer;
+
+import static com.gtnewhorizons.angelica.loading.AngelicaTweaker.LOGGER;
+
+/**
+ * Per-program compat uniform location cache and upload manager.
+ *
+ * <p>Manages {@code angelica_*} uniforms injected by {@link CompatShaderTransformer} and {@code iris_*} matrix uniforms used by Iris/celeritas shader programs.
+ */
+public class CompatUniformManager {
+
+    // Uniform location indices within the cached array (package-private for tests)
+    static final int LOC_MODELVIEW = 0;
+    static final int LOC_MODELVIEW_INVERSE = 1;
+    static final int LOC_PROJECTION = 2;
+    static final int LOC_PROJECTION_INVERSE = 3;
+    static final int LOC_NORMAL = 4;
+    static final int LOC_LIGHTMAP_TEXTURE_MATRIX = 5;
+    static final int LOC_FOG_DENSITY = 6;
+    static final int LOC_FOG_START = 7;
+    static final int LOC_FOG_END = 8;
+    static final int LOC_FOG_COLOR = 9;
+    static final int LOC_IRIS_MODELVIEW = 10;
+    static final int LOC_IRIS_PROJECTION = 11;
+    static final int LOC_IRIS_NORMAL = 12;
+    static final int LOC_IRIS_LIGHTMAP_TEXTURE_MATRIX = 13;
+    static final int LOC_ALPHA_TEST_REF = 14;
+    static final int LOC_SCENE_COLOR = 15;
+    static final int LOC_CLIP_PLANES = 16;
+    static final int LOC_CLIP_PLANES_ENABLED = 17;
+
+    // Light source fields: 12 per light × 2 lights = 24 locations
+    static final int LIGHT_FIELDS = 12;
+    static final int LF_AMBIENT = 0, LF_DIFFUSE = 1, LF_SPECULAR = 2, LF_POSITION = 3;
+    static final int LF_HALF_VECTOR = 4, LF_SPOT_DIRECTION = 5, LF_SPOT_EXPONENT = 6;
+    static final int LF_SPOT_CUTOFF = 7, LF_SPOT_COS_CUTOFF = 8;
+    static final int LF_CONSTANT_ATTEN = 9, LF_LINEAR_ATTEN = 10, LF_QUADRATIC_ATTEN = 11;
+    static final int LOC_LIGHT_BASE = 18;
+
+    // Material fields: 5 locations
+    static final int MF_EMISSION = 0, MF_AMBIENT = 1, MF_DIFFUSE = 2, MF_SPECULAR = 3, MF_SHININESS = 4;
+    static final int MAT_FIELDS = 5;
+    static final int LOC_MAT_BASE = LOC_LIGHT_BASE + 2 * LIGHT_FIELDS; // 42
+
+    static final int LOC_COUNT = LOC_MAT_BASE + MAT_FIELDS; // 47
+
+    private static final String[] LIGHT_FIELD_NAMES = {
+        "ambient", "diffuse", "specular", "position", "halfVector",
+        "spotDirection", "spotExponent", "spotCutoff", "spotCosCutoff",
+        "constantAttenuation", "linearAttenuation", "quadraticAttenuation",
+    };
+    private static final String[] MAT_FIELD_NAMES = {
+        "emission", "ambient", "diffuse", "specular", "shininess",
+    };
+
+    private static final String[] UNIFORM_NAMES;
+    static {
+        UNIFORM_NAMES = new String[LOC_COUNT];
+        UNIFORM_NAMES[LOC_MODELVIEW] = "angelica_ModelViewMatrix";
+        UNIFORM_NAMES[LOC_MODELVIEW_INVERSE] = "angelica_ModelViewMatrixInverse";
+        UNIFORM_NAMES[LOC_PROJECTION] = "angelica_ProjectionMatrix";
+        UNIFORM_NAMES[LOC_PROJECTION_INVERSE] = "angelica_ProjectionMatrixInverse";
+        UNIFORM_NAMES[LOC_NORMAL] = "angelica_NormalMatrix";
+        UNIFORM_NAMES[LOC_LIGHTMAP_TEXTURE_MATRIX] = "angelica_LightmapTextureMatrix";
+        UNIFORM_NAMES[LOC_FOG_DENSITY] = "angelica_FogDensity";
+        UNIFORM_NAMES[LOC_FOG_START] = "angelica_FogStart";
+        UNIFORM_NAMES[LOC_FOG_END] = "angelica_FogEnd";
+        UNIFORM_NAMES[LOC_FOG_COLOR] = "angelica_FogColor";
+        UNIFORM_NAMES[LOC_IRIS_MODELVIEW] = "iris_ModelViewMatrix";
+        UNIFORM_NAMES[LOC_IRIS_PROJECTION] = "iris_ProjectionMatrix";
+        UNIFORM_NAMES[LOC_IRIS_NORMAL] = "iris_NormalMatrix";
+        UNIFORM_NAMES[LOC_IRIS_LIGHTMAP_TEXTURE_MATRIX] = "iris_LightmapTextureMatrix";
+        UNIFORM_NAMES[LOC_ALPHA_TEST_REF] = "angelica_currentAlphaTest";
+        UNIFORM_NAMES[LOC_SCENE_COLOR] = "angelica_SceneColor";
+        UNIFORM_NAMES[LOC_CLIP_PLANES] = "angelica_ClipPlane[0]";
+        UNIFORM_NAMES[LOC_CLIP_PLANES_ENABLED] = "angelica_ClipPlanesEnabled";
+        for (int li = 0; li < 2; li++) {
+            for (int fi = 0; fi < LIGHT_FIELDS; fi++) {
+                UNIFORM_NAMES[LOC_LIGHT_BASE + li * LIGHT_FIELDS + fi] =
+                    "angelica_LightSource[" + li + "]." + LIGHT_FIELD_NAMES[fi];
+            }
+        }
+        for (int fi = 0; fi < MAT_FIELDS; fi++) {
+            UNIFORM_NAMES[LOC_MAT_BASE + fi] = "angelica_FrontMaterial." + MAT_FIELD_NAMES[fi];
+        }
+    }
+
+    /** Per-program cached uniform locations. Maps program ID → int[LOC_COUNT]. */
+    private static final Int2ObjectOpenHashMap<int[]> programLocations = new Int2ObjectOpenHashMap<>();
+
+    // Reusable NIO buffers for upload
+    private static final FloatBuffer mat4Buf = BufferUtils.createFloatBuffer(16);
+    private static final FloatBuffer mat3Buf = BufferUtils.createFloatBuffer(9);
+    private static final FloatBuffer vec4Buf = BufferUtils.createFloatBuffer(4);
+    private static final FloatBuffer clipPlaneBuf = BufferUtils.createFloatBuffer(32); // 8 planes * vec4
+    private static final Matrix3f normalMatrix = new Matrix3f();
+    private static final Matrix4f scratchMatrix = new Matrix4f();
+
+    private static final float LIGHTMAP_SCALE = 1.0f / 256.0f;
+    private static final FloatBuffer lightmapMatrixBuf;
+    static {
+        lightmapMatrixBuf = BufferUtils.createFloatBuffer(16);
+        new Matrix4f().scale(LIGHTMAP_SCALE).translate(8.0f, 8.0f, 8.0f).get(lightmapMatrixBuf);
+    }
+
+    // Dirty tracking: skip uploads when state hasn't changed and program is the same
+    private static int lastProgram = -1;
+    private static int lastMvGen = -1;
+    private static int lastProjGen = -1;
+    private static int lastTexMatGen = -1;
+    private static int lastFragmentGen = -1;
+    private static int lastLightingGen = -1;
+    private static int lastClipPlaneGen = -1;
+
+    private CompatUniformManager() {}
+
+    public static void onLinkProgram(int program) {
+        int[] locs = new int[LOC_COUNT];
+        boolean hasAny = false;
+
+        for (int i = 0; i < LOC_COUNT; i++) {
+            locs[i] = GL20.glGetUniformLocation(program, UNIFORM_NAMES[i]);
+            if (locs[i] != -1) hasAny = true;
+        }
+
+        if (hasAny) {
+            programLocations.put(program, locs);
+            LOGGER.debug("CompatUniformManager: program {} has compat uniforms", program);
+        }
+    }
+
+    public static void onUseProgram(int program) {
+        if (program == 0) return;
+
+        int[] locs = programLocations.get(program);
+        if (locs == null) return;
+
+        final boolean programChanged = program != lastProgram;
+        lastProgram = program;
+
+        // Matrix uniforms — skip if generation unchanged and same program
+        final int mvGen = GLStateManager.mvGeneration;
+        final int projGen = GLStateManager.projGeneration;
+        final int texMatGen = GLStateManager.texMatrixGeneration;
+        final boolean mvChanged = programChanged || mvGen != lastMvGen;
+        final boolean projChanged = programChanged || projGen != lastProjGen;
+        final boolean texMatChanged = programChanged || texMatGen != lastTexMatGen;
+        if (mvChanged || projChanged || texMatChanged) {
+            uploadMatrices(locs, mvChanged, projChanged, texMatChanged);
+            lastMvGen = mvGen;
+            lastProjGen = projGen;
+            lastTexMatGen = texMatGen;
+        }
+
+        // Fragment-category uniforms (fog, alpha) — skip if generation unchanged
+        final int fragGen = GLStateManager.fragmentGeneration;
+        if (programChanged || fragGen != lastFragmentGen) {
+            lastFragmentGen = fragGen;
+            uploadFragmentUniforms(locs);
+        }
+
+        // Lighting-derived uniforms (scene color, light sources, material)
+        final int litGen = GLStateManager.lightingGeneration;
+        if (programChanged || litGen != lastLightingGen) {
+            lastLightingGen = litGen;
+            if (locs[LOC_SCENE_COLOR] != -1) uploadSceneColor(locs);
+            uploadLightSources(locs);
+            uploadMaterial(locs);
+        }
+
+        // Clip plane equations + enabled bool — uploaded when enable state or equations change
+        if (locs[LOC_CLIP_PLANES] != -1 || locs[LOC_CLIP_PLANES_ENABLED] != -1) {
+            final int cpGen = GLStateManager.clipPlaneGeneration;
+            if (programChanged || cpGen != lastClipPlaneGen) {
+                lastClipPlaneGen = cpGen;
+                uploadClipPlanes(locs);
+            }
+        }
+    }
+
+    private static void uploadMatrices(int[] locs, boolean mvChanged, boolean projChanged, boolean texMatChanged) {
+        final Matrix4f mv = GLStateManager.getModelViewMatrix();
+        final Matrix4f proj = GLStateManager.getProjectionMatrix();
+
+        if (mvChanged) {
+            // ModelView
+            if (locs[LOC_MODELVIEW] != -1 || locs[LOC_IRIS_MODELVIEW] != -1) {
+                mv.get(mat4Buf);
+                if (locs[LOC_MODELVIEW] != -1) {
+                    GL20.glUniformMatrix4(locs[LOC_MODELVIEW], false, mat4Buf);
+                }
+                if (locs[LOC_IRIS_MODELVIEW] != -1) {
+                    GL20.glUniformMatrix4(locs[LOC_IRIS_MODELVIEW], false, mat4Buf);
+                }
+            }
+
+            // ModelView Inverse
+            if (locs[LOC_MODELVIEW_INVERSE] != -1) {
+                mv.invert(scratchMatrix);
+                scratchMatrix.get(mat4Buf);
+                GL20.glUniformMatrix4(locs[LOC_MODELVIEW_INVERSE], false, mat4Buf);
+            }
+
+            // Normal Matrix (inverse-transpose of upper-left 3x3 of ModelView)
+            if (locs[LOC_NORMAL] != -1 || locs[LOC_IRIS_NORMAL] != -1) {
+                mv.normal(normalMatrix);
+                normalMatrix.get(mat3Buf);
+                if (locs[LOC_NORMAL] != -1) {
+                    GL20.glUniformMatrix3(locs[LOC_NORMAL], false, mat3Buf);
+                }
+                if (locs[LOC_IRIS_NORMAL] != -1) {
+                    GL20.glUniformMatrix3(locs[LOC_IRIS_NORMAL], false, mat3Buf);
+                }
+            }
+        }
+
+        if (projChanged) {
+            // Projection
+            if (locs[LOC_PROJECTION] != -1 || locs[LOC_IRIS_PROJECTION] != -1) {
+                proj.get(mat4Buf);
+                if (locs[LOC_PROJECTION] != -1) {
+                    GL20.glUniformMatrix4(locs[LOC_PROJECTION], false, mat4Buf);
+                }
+                if (locs[LOC_IRIS_PROJECTION] != -1) {
+                    GL20.glUniformMatrix4(locs[LOC_IRIS_PROJECTION], false, mat4Buf);
+                }
+            }
+
+            // Projection Inverse
+            if (locs[LOC_PROJECTION_INVERSE] != -1) {
+                proj.invert(scratchMatrix);
+                scratchMatrix.get(mat4Buf);
+                GL20.glUniformMatrix4(locs[LOC_PROJECTION_INVERSE], false, mat4Buf);
+            }
+        }
+
+        if (texMatChanged) {
+            // Iris lightmap texture matrix (constant)
+            if (locs[LOC_IRIS_LIGHTMAP_TEXTURE_MATRIX] != -1) {
+                GL20.glUniformMatrix4(locs[LOC_IRIS_LIGHTMAP_TEXTURE_MATRIX], false, lightmapMatrixBuf);
+            }
+
+            // angelica_LightmapTextureMatrix — actual GLSM texture unit 1 matrix (set by enableLightmap())
+            if (locs[LOC_LIGHTMAP_TEXTURE_MATRIX] != -1) {
+                GLStateManager.getTextures().getTextureUnitMatrix(1).get(mat4Buf);
+                GL20.glUniformMatrix4(locs[LOC_LIGHTMAP_TEXTURE_MATRIX], false, mat4Buf);
+            }
+        }
+    }
+
+    private static void uploadFragmentUniforms(int[] locs) {
+        // Fog uniforms
+        FogStateStack fog = GLStateManager.getFogState();
+        if (locs[LOC_FOG_DENSITY] != -1) {
+            GL20.glUniform1f(locs[LOC_FOG_DENSITY], Math.max(0.0f, fog.getDensity()));
+        }
+        if (locs[LOC_FOG_START] != -1) {
+            GL20.glUniform1f(locs[LOC_FOG_START], fog.getStart());
+        }
+        if (locs[LOC_FOG_END] != -1) {
+            GL20.glUniform1f(locs[LOC_FOG_END], fog.getEnd());
+        }
+        if (locs[LOC_FOG_COLOR] != -1) {
+            vec4Buf.clear();
+            vec4Buf.put((float) fog.getFogColor().x).put((float) fog.getFogColor().y)
+                   .put((float) fog.getFogColor().z).put(fog.getFogAlpha());
+            vec4Buf.flip();
+            GL20.glUniform4(locs[LOC_FOG_COLOR], vec4Buf);
+        }
+
+        // Alpha test reference — core profile replacement for GL_ALPHA_TEST
+        // Return -1.0f for ALWAYS or disabled so `alpha <= ref` never discards.
+        if (locs[LOC_ALPHA_TEST_REF] != -1) {
+            final float ref;
+            if (!GLStateManager.getAlphaTest().isEnabled()
+                || GLStateManager.getAlphaState().getFunction() == GL11.GL_ALWAYS) {
+                ref = -1.0f;
+            } else {
+                ref = GLStateManager.getAlphaState().getReference();
+            }
+            GL20.glUniform1f(locs[LOC_ALPHA_TEST_REF], ref);
+        }
+    }
+
+    /**
+     * Scene color = emission + ambient * lightModel.ambient, alpha = diffuse.a
+     * Same computation as {@code Uniforms.uploadLightingPreComputed()}.
+     */
+    private static void uploadSceneColor(int[] locs) {
+        final MaterialState mat = GLStateManager.getFrontMaterial();
+        final LightModelState lm = GLStateManager.getLightModel();
+        vec4Buf.clear();
+        vec4Buf.put(mat.emission.x + mat.ambient.x * lm.ambient.x)
+               .put(mat.emission.y + mat.ambient.y * lm.ambient.y)
+               .put(mat.emission.z + mat.ambient.z * lm.ambient.z)
+               .put(mat.diffuse.w);
+        vec4Buf.flip();
+        GL20.glUniform4(locs[LOC_SCENE_COLOR], vec4Buf);
+    }
+
+    private static void uploadLightSources(int[] locs) {
+        // Early exit: if the first light field isn't present, no lighting uniforms exist
+        if (locs[LOC_LIGHT_BASE] == -1) return;
+        final LightStateStack[] lights = GLStateManager.getLightDataStates();
+        for (int li = 0; li < 2; li++) {
+            final int base = LOC_LIGHT_BASE + li * LIGHT_FIELDS;
+            final LightState light = lights[li];
+
+            if (locs[base + LF_AMBIENT] != -1)
+                GL20.glUniform4f(locs[base + LF_AMBIENT], light.ambient.x, light.ambient.y, light.ambient.z, light.ambient.w);
+            if (locs[base + LF_DIFFUSE] != -1)
+                GL20.glUniform4f(locs[base + LF_DIFFUSE], light.diffuse.x, light.diffuse.y, light.diffuse.z, light.diffuse.w);
+            if (locs[base + LF_SPECULAR] != -1)
+                GL20.glUniform4f(locs[base + LF_SPECULAR], light.specular.x, light.specular.y, light.specular.z, light.specular.w);
+            if (locs[base + LF_POSITION] != -1)
+                GL20.glUniform4f(locs[base + LF_POSITION], light.position.x, light.position.y, light.position.z, light.position.w);
+            if (locs[base + LF_HALF_VECTOR] != -1) {
+                // halfVector = normalize(normalize(position.xyz) + eye), eye=(0,0,1) for infinite viewer
+                float hx, hy, hz;
+                if (light.position.w == 0.0f) {
+                    float len = (float) Math.sqrt(light.position.x * light.position.x
+                        + light.position.y * light.position.y + light.position.z * light.position.z);
+                    if (len > 0) {
+                        hx = light.position.x / len;
+                        hy = light.position.y / len;
+                        hz = light.position.z / len + 1.0f;
+                    } else {
+                        hx = 0; hy = 0; hz = 1;
+                    }
+                } else {
+                    hx = 0; hy = 0; hz = 1;
+                }
+                float hlen = (float) Math.sqrt(hx * hx + hy * hy + hz * hz);
+                if (hlen > 0) { hx /= hlen; hy /= hlen; hz /= hlen; }
+                GL20.glUniform4f(locs[base + LF_HALF_VECTOR], hx, hy, hz, 0.0f);
+            }
+            if (locs[base + LF_SPOT_DIRECTION] != -1)
+                GL20.glUniform3f(locs[base + LF_SPOT_DIRECTION], light.spotDirection.x, light.spotDirection.y, light.spotDirection.z);
+            if (locs[base + LF_SPOT_EXPONENT] != -1)
+                GL20.glUniform1f(locs[base + LF_SPOT_EXPONENT], light.spotExponent);
+            if (locs[base + LF_SPOT_CUTOFF] != -1)
+                GL20.glUniform1f(locs[base + LF_SPOT_CUTOFF], light.spotCutoff);
+            if (locs[base + LF_SPOT_COS_CUTOFF] != -1)
+                GL20.glUniform1f(locs[base + LF_SPOT_COS_CUTOFF], light.spotCosCutoff);
+            if (locs[base + LF_CONSTANT_ATTEN] != -1)
+                GL20.glUniform1f(locs[base + LF_CONSTANT_ATTEN], light.constantAttenuation);
+            if (locs[base + LF_LINEAR_ATTEN] != -1)
+                GL20.glUniform1f(locs[base + LF_LINEAR_ATTEN], light.linearAttenuation);
+            if (locs[base + LF_QUADRATIC_ATTEN] != -1)
+                GL20.glUniform1f(locs[base + LF_QUADRATIC_ATTEN], light.quadraticAttenuation);
+        }
+    }
+
+    private static void uploadMaterial(int[] locs) {
+        // Early exit: if the first material field isn't present, no material uniforms exist
+        if (locs[LOC_MAT_BASE] == -1) return;
+        final MaterialState mat = GLStateManager.getFrontMaterial();
+        if (locs[LOC_MAT_BASE + MF_EMISSION] != -1)
+            GL20.glUniform4f(locs[LOC_MAT_BASE + MF_EMISSION], mat.emission.x, mat.emission.y, mat.emission.z, mat.emission.w);
+        if (locs[LOC_MAT_BASE + MF_AMBIENT] != -1)
+            GL20.glUniform4f(locs[LOC_MAT_BASE + MF_AMBIENT], mat.ambient.x, mat.ambient.y, mat.ambient.z, mat.ambient.w);
+        if (locs[LOC_MAT_BASE + MF_DIFFUSE] != -1)
+            GL20.glUniform4f(locs[LOC_MAT_BASE + MF_DIFFUSE], mat.diffuse.x, mat.diffuse.y, mat.diffuse.z, mat.diffuse.w);
+        if (locs[LOC_MAT_BASE + MF_SPECULAR] != -1)
+            GL20.glUniform4f(locs[LOC_MAT_BASE + MF_SPECULAR], mat.specular.x, mat.specular.y, mat.specular.z, mat.specular.w);
+        if (locs[LOC_MAT_BASE + MF_SHININESS] != -1)
+            GL20.glUniform1f(locs[LOC_MAT_BASE + MF_SHININESS], mat.shininess);
+    }
+
+    private static void uploadClipPlanes(int[] locs) {
+        if (locs[LOC_CLIP_PLANES_ENABLED] != -1) {
+            GL20.glUniform1i(locs[LOC_CLIP_PLANES_ENABLED], GLStateManager.anyClipPlaneEnabled() ? 1 : 0);
+        }
+        if (locs[LOC_CLIP_PLANES] != -1) {
+            final ClipPlaneState cps = GLStateManager.getClipPlaneState();
+            clipPlaneBuf.clear();
+            for (int i = 0; i < GLStateManager.MAX_CLIP_PLANES; i++) {
+                cps.putEyePlane(i, clipPlaneBuf);
+            }
+            clipPlaneBuf.flip();
+            GL20.glUniform4(locs[LOC_CLIP_PLANES], clipPlaneBuf);
+        }
+    }
+
+    public static void onDeleteProgram(int program) {
+        programLocations.remove(program);
+    }
+
+    public static boolean hasProgram(int program) {
+        return programLocations.containsKey(program);
+    }
+
+    public static int[] getLocations(int program) {
+        return programLocations.get(program);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/CompiledFormatBuffer.java

@@ -1,23 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-
-/**
- * A compiled VBO with its associated draw ranges.
- * All ranges reference vertices within this single VBO.
- * <p>
- * Contains two range arrays:
- * <ul>
- *   <li><b>mergedRanges</b>: For optimized path - consecutive same-transform draws merged</li>
- *   <li><b>perDrawRanges</b>: For unoptimized path - 1:1 with original draws</li>
- * </ul>
- */
-@Desugar
-public record CompiledFormatBuffer(
-    VertexBuffer vbo,
-    CapturingTessellator.Flags flags,
-    DrawRange[] mergedRanges,
-    DrawRange[] perDrawRanges
-) {}

src/main/java/com/gtnewhorizons/angelica/glsm/CompiledLineBuffer.java

@@ -1,21 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-
-/**
- * A compiled VBO containing all line geometry with associated draw ranges.
- * All ranges reference vertices within this single VBO.
- * <p>
- * Contains two range arrays:
- * <ul>
- *   <li><b>mergedRanges</b>: For optimized path - consecutive same-transform draws merged</li>
- *   <li><b>perDrawRanges</b>: For unoptimized path - 1:1 with original draws</li>
- * </ul>
- */
-@Desugar
-public record CompiledLineBuffer(
-    VertexBuffer vbo,
-    DrawRange[] mergedRanges,
-    DrawRange[] perDrawRanges
-) {}

src/main/java/com/gtnewhorizons/angelica/glsm/CompiledPrimitiveBuffers.java

@@ -1,31 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-
-/**
- * Compiled VBOs containing tessellator primitives (lines and triangles) for a single vertex format.
- * Separate VBOs are used for lines (GL_LINES) and triangles (GL_TRIANGLES) since they have different draw modes.
- * <p>
- * Contains range arrays for both optimized (merged) and unoptimized (per-draw) paths.
- * Similar to CompiledFormatBuffer but handles primitives instead of quads.
- */
-@Desugar
-public record CompiledPrimitiveBuffers(
-    CapturingTessellator.Flags flags,
-    VertexBuffer lineVbo,
-    DrawRange[] lineMergedRanges,
-    DrawRange[] linePerDrawRanges,
-    VertexBuffer triangleVbo,
-    DrawRange[] triangleMergedRanges,
-    DrawRange[] trianglePerDrawRanges
-) {
-    public boolean hasLines() {
-        return lineVbo != null;
-    }
-
-    public boolean hasTriangles() {
-        return triangleVbo != null;
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/DisplayListIDAllocator.java

@@ -0,0 +1,187 @@
+package com.gtnewhorizons.angelica.glsm;
+
+/*
+ * Ported from Mesa's util_idalloc (src/util/u_idalloc.c).
+ *
+ * Original copyright and license:
+ *
+ * Copyright 2017 Valve Corporation
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Original author: Samuel Pitoiset <[email protected]>
+ */
+
+/**
+ * Bitmap ID allocator for display list IDs.
+ *
+ * <p>Bitmap-based: each bit in the {@code data} array represents one ID.
+ * Bit set = allocated, bit clear = free. ID 0 is reserved (never returned).
+ */
+public class DisplayListIDAllocator {
+
+    private int[] data;
+    private int numElements;       // number of uint32 words allocated
+    private int numSetElements;    // highest word index with any bit set + 1
+    private int lowestFreeIdx;     // optimization: skip fully-allocated words
+
+    public DisplayListIDAllocator() {
+        this(32); // 1024 IDs initially
+    }
+
+    public DisplayListIDAllocator(int initialWords) {
+        if (initialWords < 1) initialWords = 1;
+        this.data = new int[initialWords];
+        this.numElements = initialWords;
+        this.numSetElements = 0;
+        this.lowestFreeIdx = 0;
+        // Reserve ID 0 (never returned), matching Mesa's skip_zero pattern
+        data[0] = 1;
+        numSetElements = 1;
+    }
+
+    public int allocRange(int count) {
+        if (count <= 0) throw new IllegalArgumentException("count must be > 0");
+        if (count == 1) return allocSingle();
+        return allocMultiple(count);
+    }
+
+    private int allocSingle() {
+        for (int i = lowestFreeIdx; i < numElements; i++) {
+            if (data[i] == 0xFFFFFFFF) continue;
+
+            int bit = Integer.numberOfTrailingZeros(~data[i]);
+            data[i] |= 1 << bit;
+            lowestFreeIdx = i;
+            numSetElements = Math.max(numSetElements, i + 1);
+            return i * 32 + bit;
+        }
+
+        // No slots available, grow. Record old end, then mark first bit there.
+        int oldNumElements = numElements;
+        resize(Math.max(numElements, 1) * 2);
+        lowestFreeIdx = oldNumElements;
+        data[oldNumElements] |= 1;
+        numSetElements = Math.max(numSetElements, oldNumElements + 1);
+        return oldNumElements * 32;
+    }
+
+    private int allocMultiple(int num) {
+        int numWords = divRoundUp(num, 32);
+        int base = findFreeBlock(lowestFreeIdx);
+        boolean found = false;
+
+        while (!found) {
+            int i;
+            for (i = base; i < numElements && i - base < numWords && data[i] == 0; i++)
+                ;
+
+            if (i - base == numWords) {
+                found = true;
+            } else if (i == numElements) {
+                // Hit end — base is valid: data[base..end] are zero, resize extends the run into newly zeroed words.
+                resize(numElements * 2 + numWords);
+                found = true;
+            } else {
+                // Non-zero word at i, skip past it
+                base = i + 1;
+            }
+        }
+
+        // Mark bits as used
+        int fullWords = num / 32;
+        int remainder = num % 32;
+        for (int i = base; i < base + fullWords; i++) {
+            data[i] = 0xFFFFFFFF;
+        }
+        if (remainder != 0) {
+            data[base + fullWords] |= (1 << remainder) - 1;
+        }
+
+        if (lowestFreeIdx == base) {
+            lowestFreeIdx = base + num / 32;
+        }
+        numSetElements = Math.max(numSetElements, base + numWords);
+
+        return base * 32;
+    }
+
+    private int findFreeBlock(int start) {
+        for (int i = start; i < numElements; i++) {
+            if (data[i] == 0) return i;
+        }
+        return numElements;
+    }
+
+    public void free(int id) {
+        if (id <= 0) return; // ID 0 is reserved
+        int idx = id / 32;
+        if (idx >= numElements) return;
+
+        lowestFreeIdx = Math.min(idx, lowestFreeIdx);
+        data[idx] &= ~(1 << (id % 32));
+
+        if (numSetElements == idx + 1) {
+            while (numSetElements > 0 && data[numSetElements - 1] == 0) {
+                numSetElements--;
+            }
+        }
+    }
+
+    public void freeRange(int base, int count) {
+        if (count <= 0 || base <= 0) return;
+
+        int startIdx = base / 32;
+        if (startIdx >= numElements) return;
+
+        int end = base + count;
+        for (int id = base; id < end; id++) {
+            int idx = id / 32;
+            if (idx >= numElements) break;
+            data[idx] &= ~(1 << (id % 32));
+        }
+
+        lowestFreeIdx = Math.min(startIdx, lowestFreeIdx);
+        while (numSetElements > 0 && data[numSetElements - 1] == 0) {
+            numSetElements--;
+        }
+    }
+
+    public boolean isAllocated(int id) {
+        if (id <= 0) return false;
+        int idx = id / 32;
+        if (idx >= numSetElements) return false;
+        return (data[idx] & (1 << (id % 32))) != 0;
+    }
+
+    private void resize(int newNumElements) {
+        if (newNumElements <= numElements) return;
+        int[] newData = new int[newNumElements];
+        System.arraycopy(data, 0, newData, 0, numElements);
+        data = newData;
+        numElements = newNumElements;
+    }
+
+    private static int divRoundUp(int a, int b) {
+        return (a + b - 1) / b;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/DrawRange.java

@@ -1,25 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizons.angelica.glsm.recording.AccumulatedDraw;
-import org.joml.Matrix4f;
-
-/**
- * Represents a vertex range within a shared VBO, along with its transform.
- * Used during format-based batching to track where each draw's vertices are stored.
- *
- * <p>The restoreData field holds last vertex attributes for GL state restoration
- * after VBO rendering (immediate mode draws only). Null for tessellator draws.
- */
-@Desugar
-public record DrawRange(
-    int startVertex,
-    int vertexCount,
-    Matrix4f transform,
-    int commandIndex,
-    AccumulatedDraw.RestoreData restoreData
-) {
-    DrawRange(int startVertex, int vertexCount, Matrix4f transform, int commandIndex) {
-        this(startVertex, vertexCount, transform, commandIndex, null);
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/DrawRangeWithBuffer.java

@@ -1,43 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-
-/**
- * Helper record pairing a DrawRange with its VBO and vertex format flags.
- * Used for sorting ranges by command index while retaining VBO reference.
- * Works for both quad ranges (from CompiledFormatBuffer) and line ranges (from CompiledLineBuffer).
- */
-@Desugar
-record DrawRangeWithBuffer(
-    DrawRange range,
-    VertexBuffer vbo,
-    CapturingTessellator.Flags flags,
-    DrawSource source
-) {
-    boolean hasBrightness() {
-        return flags != null && flags.hasBrightness;
-    }
-
-    /**
-     * Source of a draw command for debug logging.
-     */
-    enum DrawSource {
-        TESSELLATOR_QUADS("tessellator quads"),
-        TESSELLATOR_LINES("tessellator lines"),
-        TESSELLATOR_TRIANGLES("tessellator triangles"),
-        IMMEDIATE_MODE_LINES("immediate mode lines");
-
-        private final String description;
-
-        DrawSource(String description) {
-            this.description = description;
-        }
-
-        @Override
-        public String toString() {
-            return description;
-        }
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/Feature.java

@@ -2,6 +2,7 @@ package com.gtnewhorizons.angelica.glsm;
 
 import com.google.common.collect.ImmutableSet;
 import com.gtnewhorizon.gtnhlib.client.renderer.stacks.IStateStack;
+import com.gtnewhorizons.angelica.glsm.ffp.ShaderManager;
 import com.gtnewhorizons.angelica.glsm.stacks.BooleanStateStack;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
@@ -87,22 +88,20 @@ public class Feature {
               GLStateManager.alphaTest  // GL_ALPHA_TEST enable bit
             , GLStateManager.alphaState // Alpha test function and reference value
             , GLStateManager.blendMode  // GL_BLEND enable bit
-            , GLStateManager.blendState // Blending source and destination functions
-            // Constant blend color
-            // Blending equation
+            , GLStateManager.blendState // Blending source/destination functions, equation, blend color
             , GLStateManager.colorLogicOpState // GL_COLOR_LOGIC_OP enable bit
             , GLStateManager.ditherState // GL_DITHER enable bit
             , GLStateManager.drawBuffer // GL_DRAW_BUFFER setting
             , GLStateManager.indexLogicOpState // GL_INDEX_LOGIC_OP enable bit
-            // Logic op function
+            , GLStateManager.logicOpMode // Logic op function
             , GLStateManager.colorMask   // Color-mode and index-mode writemasks
             , GLStateManager.clearColor  // Color-mode and index-mode clear values
         ));
         attribToFeatures.put(GL11.GL_CURRENT_BIT, ImmutableSet.of(
               GLStateManager.color  // Current RGBA color
+            , ShaderManager.getNormalStack()    // Current normal vector
+            , ShaderManager.getTexCoordStack()  // Current texture coordinates
             // Current color index
-            // Current normal vector
-            // Current texture coordinates
             // Current raster position
             // GL_CURRENT_RASTER_POSITION_VALID flag
             // RGBA color associated with current raster position
@@ -300,6 +299,7 @@ public class Feature {
         ));
         final Set<IStateStack<?>> textureAttribs = new HashSet<>(ImmutableSet.of(
             GLStateManager.activeTextureUnit // Active texture unit
+                // GL_TEXTURE_ENV_MODE + GL_TEXTURE_ENV_COLOR — now per-unit in TexEnvState (added below)
                 // Enable bits for the four texture coordinates
 
                 // Border color for each texture image
@@ -307,17 +307,16 @@ public class Feature {
                 // Magnification function for each texture image
                 // Texture coordinates and wrap mode for each texture image
 
-                // Color and mode for each texture environment
                 // Enable bits GL_TEXTURE_GEN_x, x is S, T, R, and Q
                 // GL_TEXTURE_GEN_MODE setting for S, T, R, and Q
                 // glTexGen plane equations for S, T, R, and Q
                 // Current texture bindings (for example, GL_TEXTURE_BINDING_2D) - Below
         ));
 
-        // Current Texture Bindings - GL_TEXTURE_BINDING_2D
+        // Current Texture Bindings - GL_TEXTURE_BINDING_2D + per-unit TexEnvState
         for(int i = 0 ; i < GLStateManager.MAX_TEXTURE_UNITS; i++) {
             textureAttribs.add(GLStateManager.textures.getTextureUnitBindings(i));
-//            textureAttribs.add(GLStateManager.textures.getInfo(i))
+            textureAttribs.add(GLStateManager.textures.getTexEnvState(i));
         }
 
         // Enable bits GL_TEXTURE_GEN_x where x is S, T, R, or Q

src/main/java/com/gtnewhorizons/angelica/glsm/FeedbackManager.java

@@ -0,0 +1,359 @@
+package com.gtnewhorizons.angelica.glsm;
+
+import com.gtnewhorizons.angelica.glsm.recording.ImmediateModeRecorder;
+import com.gtnewhorizons.angelica.glsm.states.VertexAttribState;
+import com.gtnewhorizons.angelica.glsm.states.ViewportState;
+import com.gtnewhorizons.angelica.loading.AngelicaTweaker;
+import org.joml.Matrix4f;
+import org.joml.Vector4f;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL15;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+import java.nio.ShortBuffer;
+
+/**
+ * Software emulation of GL feedback mode
+ */
+public class FeedbackManager {
+
+    private static final int FB_3D = 0x01;
+    private static final int FB_4D = 0x02;
+    private static final int FB_COLOR = 0x04;
+    private static final int FB_TEXTURE = 0x08;
+
+    private static int renderMode = GL11.GL_RENDER;
+    private static FloatBuffer feedbackBuffer;
+    private static int feedbackBufferSize;
+    private static int feedbackMask;
+    private static int feedbackCount;
+
+    private static final Matrix4f mvpMatrix = new Matrix4f();
+    private static final Vector4f clipVec = new Vector4f();
+
+    private static ByteBuffer readbackBuf = ByteBuffer.allocateDirect(256 * 1024).order(ByteOrder.nativeOrder());
+    private static ByteBuffer indexReadbackBuf = ByteBuffer.allocateDirect(4 * 1024).order(ByteOrder.nativeOrder());
+
+    @FunctionalInterface
+    private interface IndexReader {
+        int read(int i);
+    }
+
+    public static boolean isFeedbackMode() {
+        return renderMode == GL11.GL_FEEDBACK;
+    }
+
+    public static void glFeedbackBuffer(int type, FloatBuffer buffer) {
+        if (renderMode == GL11.GL_FEEDBACK) {
+            AngelicaTweaker.LOGGER.error("glFeedbackBuffer called while already in feedback mode");
+            return;
+        }
+        feedbackBuffer = buffer;
+        feedbackBufferSize = buffer.remaining();
+        feedbackMask = computeMask(type);
+        feedbackCount = 0;
+    }
+
+    public static int glRenderMode(int mode) {
+        int result = switch (renderMode) {
+            case GL11.GL_FEEDBACK -> (feedbackCount > feedbackBufferSize) ? -1 : feedbackCount;
+            case GL11.GL_RENDER, GL11.GL_SELECT -> 0;
+            default -> 0;
+        };
+
+        if (mode == GL11.GL_SELECT) {
+            AngelicaTweaker.LOGGER.warn("glRenderMode(GL_SELECT): selection mode not emulated");
+        }
+
+        feedbackCount = 0;
+        renderMode = mode;
+        return result;
+    }
+
+    public static void glPassThrough(float token) {
+        if (renderMode == GL11.GL_FEEDBACK) {
+            feedbackToken(GL11.GL_PASS_THROUGH_TOKEN);
+            feedbackToken(token);
+        }
+    }
+
+    private static void feedbackToken(float token) {
+        if (feedbackCount < feedbackBufferSize) {
+            feedbackBuffer.put(feedbackBuffer.position() + feedbackCount, token);
+        }
+        feedbackCount++;
+    }
+
+    private static void feedbackVertex(float winX, float winY, float winZ, float winW) {
+        feedbackToken(winX);
+        feedbackToken(winY);
+        if ((feedbackMask & FB_3D) != 0) feedbackToken(winZ);
+        if ((feedbackMask & FB_4D) != 0) feedbackToken(winW);
+        if ((feedbackMask & FB_COLOR) != 0) {
+            feedbackToken(1f);
+            feedbackToken(1f);
+            feedbackToken(1f);
+            feedbackToken(1f);
+        }
+        if ((feedbackMask & FB_TEXTURE) != 0) {
+            feedbackToken(0f);
+            feedbackToken(0f);
+            feedbackToken(0f);
+            feedbackToken(1f);
+        }
+    }
+
+    private static void transformAndEmitVertex(float x, float y, float z) {
+        clipVec.set(x, y, z, 1.0f);
+        mvpMatrix.transform(clipVec);
+
+        final float w = clipVec.w;
+        final float ndcX = clipVec.x / w;
+        final float ndcY = clipVec.y / w;
+        final float ndcZ = clipVec.z / w;
+
+        final ViewportState vp = GLStateManager.getViewportState();
+        final float winX = vp.x + vp.width * (ndcX + 1.0f) * 0.5f;
+        final float winY = vp.y + vp.height * (ndcY + 1.0f) * 0.5f;
+        final float winZ = (float) ((vp.depthRangeFar - vp.depthRangeNear) * ndcZ
+            + (vp.depthRangeFar + vp.depthRangeNear)) * 0.5f;
+        final float winW = 1.0f / w;
+
+        feedbackVertex(winX, winY, winZ, winW);
+    }
+
+    private static int positionStride() {
+        final int s = VertexAttribState.get(0).effectiveStride();
+        return (s != 0) ? s : 12;
+    }
+
+    private static long positionOffset() {
+        return VertexAttribState.get(0).offset;
+    }
+
+    public static void processDrawArrays(int mode, int first, int count) {
+        computeMVP();
+        final int stride = positionStride();
+        final long posOffset = positionOffset();
+        final int byteCount = count * stride;
+        ensureReadbackCapacity(byteCount);
+        readbackBuf.clear().limit(byteCount);
+        GL15.glGetBufferSubData(GL15.GL_ARRAY_BUFFER, (long) first * stride + posOffset, readbackBuf);
+
+        emitAllPrimitives(mode, count, i -> i, stride);
+    }
+
+    public static void processDrawElements(int mode, int indexCount, int type, long eboOffset) {
+        computeMVP();
+        final int stride = positionStride();
+
+        final int elementSize = VertexAttribState.Attrib.glTypeSizeBytes(type);
+        final int indexByteCount = indexCount * elementSize;
+        ensureIndexReadbackCapacity(indexByteCount);
+        indexReadbackBuf.clear().limit(indexByteCount);
+        GL15.glGetBufferSubData(GL15.GL_ELEMENT_ARRAY_BUFFER, eboOffset, indexReadbackBuf);
+        final ByteBuffer indexBuf = indexReadbackBuf;
+
+        int minIdx = Integer.MAX_VALUE, maxIdx = Integer.MIN_VALUE;
+        for (int i = 0; i < indexCount; i++) {
+            final int idx = ImmediateModeRecorder.readIndex(indexBuf, type, 0, i);
+            if (idx < minIdx) minIdx = idx;
+            if (idx > maxIdx) maxIdx = idx;
+        }
+
+        final long posOffset = positionOffset();
+        final int vertexCount = maxIdx - minIdx + 1;
+        final int byteCount = vertexCount * stride;
+        ensureReadbackCapacity(byteCount);
+        readbackBuf.clear().limit(byteCount);
+        GL15.glGetBufferSubData(GL15.GL_ARRAY_BUFFER, (long) minIdx * stride + posOffset, readbackBuf);
+
+        final int base = minIdx;
+        emitAllPrimitives(mode, indexCount, i -> ImmediateModeRecorder.readIndex(indexBuf, type, 0, i) - base, stride);
+    }
+
+    public static void processDrawElements(int mode, ByteBuffer indices) {
+        final int basePos = indices.position();
+        processDrawElementsImpl(mode, indices.remaining(), i -> indices.get(basePos + i) & 0xFF);
+    }
+
+    public static void processDrawElements(int mode, ShortBuffer indices) {
+        final int basePos = indices.position();
+        processDrawElementsImpl(mode, indices.remaining(), i -> indices.get(basePos + i) & 0xFFFF);
+    }
+
+    public static void processDrawElements(int mode, IntBuffer indices) {
+        final int basePos = indices.position();
+        processDrawElementsImpl(mode, indices.remaining(), i -> indices.get(basePos + i));
+    }
+
+    public static void processDrawElements(int mode, int count, int type, ByteBuffer indices) {
+        final int pos = indices.position();
+        final IndexReader reader = switch (type) {
+            case GL11.GL_UNSIGNED_BYTE -> i -> indices.get(pos + i) & 0xFF;
+            case GL11.GL_UNSIGNED_SHORT -> i -> indices.getShort(pos + i * 2) & 0xFFFF;
+            case GL11.GL_UNSIGNED_INT -> i -> indices.getInt(pos + i * 4);
+            default -> i -> 0;
+        };
+        processDrawElementsImpl(mode, count, reader);
+    }
+
+    private static void processDrawElementsImpl(int mode, int count, IndexReader reader) {
+        computeMVP();
+        final int stride = positionStride();
+
+        int minIdx = Integer.MAX_VALUE, maxIdx = Integer.MIN_VALUE;
+        for (int i = 0; i < count; i++) {
+            final int idx = reader.read(i);
+            if (idx < minIdx) minIdx = idx;
+            if (idx > maxIdx) maxIdx = idx;
+        }
+
+        readVerticesFromVBO(minIdx, maxIdx, stride);
+        final int base = minIdx;
+        emitAllPrimitives(mode, count, i -> reader.read(i) - base, stride);
+    }
+
+    private static void computeMVP() {
+        mvpMatrix.set(GLStateManager.getProjectionMatrix()).mul(GLStateManager.getModelViewMatrix());
+    }
+
+    private static int computeMask(int type) {
+        return switch (type) {
+            case GL11.GL_2D -> 0;
+            case GL11.GL_3D -> FB_3D;
+            case GL11.GL_3D_COLOR -> FB_3D | FB_COLOR;
+            case GL11.GL_3D_COLOR_TEXTURE -> FB_3D | FB_COLOR | FB_TEXTURE;
+            case GL11.GL_4D_COLOR_TEXTURE -> FB_3D | FB_4D | FB_COLOR | FB_TEXTURE;
+            default -> 0;
+        };
+    }
+
+    private static void ensureReadbackCapacity(int bytes) {
+        if (readbackBuf.capacity() < bytes) {
+            readbackBuf = ByteBuffer.allocateDirect(bytes).order(ByteOrder.nativeOrder());
+        }
+    }
+
+    private static void ensureIndexReadbackCapacity(int bytes) {
+        if (indexReadbackBuf.capacity() < bytes) {
+            indexReadbackBuf = ByteBuffer.allocateDirect(bytes).order(ByteOrder.nativeOrder());
+        }
+    }
+
+    private static void readVerticesFromVBO(int minIdx, int maxIdx, int stride) {
+        final long posOffset = positionOffset();
+        final int vertexCount = maxIdx - minIdx + 1;
+        final int byteCount = vertexCount * stride;
+        ensureReadbackCapacity(byteCount);
+        readbackBuf.clear().limit(byteCount);
+        GL15.glGetBufferSubData(GL15.GL_ARRAY_BUFFER, (long) minIdx * stride + posOffset, readbackBuf);
+    }
+
+    private static void emitVertex(int vertexIndex, int stride) {
+        final float x = readbackBuf.getFloat(vertexIndex * stride);
+        final float y = readbackBuf.getFloat(vertexIndex * stride + 4);
+        final float z = readbackBuf.getFloat(vertexIndex * stride + 8);
+        transformAndEmitVertex(x, y, z);
+    }
+
+    private static void emitAllPrimitives(int mode, int count, IndexReader reader, int stride) {
+        switch (mode) {
+            case GL11.GL_POINTS:
+                for (int i = 0; i < count; i++) {
+                    feedbackToken(GL11.GL_POINT_TOKEN);
+                    emitVertex(reader.read(i), stride);
+                }
+                break;
+
+            case GL11.GL_LINES:
+                for (int i = 0; i + 1 < count; i += 2) {
+                    feedbackToken(i == 0 ? GL11.GL_LINE_RESET_TOKEN : GL11.GL_LINE_TOKEN);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                }
+                break;
+
+            case GL11.GL_LINE_STRIP:
+                for (int i = 0; i + 1 < count; i++) {
+                    feedbackToken(i == 0 ? GL11.GL_LINE_RESET_TOKEN : GL11.GL_LINE_TOKEN);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                }
+                break;
+
+            case GL11.GL_LINE_LOOP:
+                for (int i = 0; i + 1 < count; i++) {
+                    feedbackToken(i == 0 ? GL11.GL_LINE_RESET_TOKEN : GL11.GL_LINE_TOKEN);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                }
+                if (count > 2) {
+                    feedbackToken(GL11.GL_LINE_TOKEN);
+                    emitVertex(reader.read(count - 1), stride);
+                    emitVertex(reader.read(0), stride);
+                }
+                break;
+
+            case GL11.GL_TRIANGLES:
+                for (int i = 0; i + 2 < count; i += 3) {
+                    feedbackToken(GL11.GL_POLYGON_TOKEN);
+                    feedbackToken(3);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                    emitVertex(reader.read(i + 2), stride);
+                }
+                break;
+
+            case GL11.GL_TRIANGLE_STRIP:
+                for (int i = 0; i + 2 < count; i++) {
+                    feedbackToken(GL11.GL_POLYGON_TOKEN);
+                    feedbackToken(3);
+                    if ((i & 1) == 0) {
+                        emitVertex(reader.read(i), stride);
+                        emitVertex(reader.read(i + 1), stride);
+                    } else {
+                        emitVertex(reader.read(i + 1), stride);
+                        emitVertex(reader.read(i), stride);
+                    }
+                    emitVertex(reader.read(i + 2), stride);
+                }
+                break;
+
+            case GL11.GL_TRIANGLE_FAN:
+                for (int i = 1; i + 1 < count; i++) {
+                    feedbackToken(GL11.GL_POLYGON_TOKEN);
+                    feedbackToken(3);
+                    emitVertex(reader.read(0), stride);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                }
+                break;
+
+            case GL11.GL_QUADS:
+                for (int i = 0; i + 3 < count; i += 4) {
+                    feedbackToken(GL11.GL_POLYGON_TOKEN);
+                    feedbackToken(4);
+                    emitVertex(reader.read(i), stride);
+                    emitVertex(reader.read(i + 1), stride);
+                    emitVertex(reader.read(i + 2), stride);
+                    emitVertex(reader.read(i + 3), stride);
+                }
+                break;
+
+            default:
+                throw new UnsupportedOperationException("Feedback mode: unsupported primitive mode 0x" + Integer.toHexString(mode));
+        }
+    }
+
+    static void reset() {
+        renderMode = GL11.GL_RENDER;
+        feedbackBuffer = null;
+        feedbackBufferSize = 0;
+        feedbackMask = 0;
+        feedbackCount = 0;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/FormatBuffer.java

@@ -1,106 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.quad.ModelQuadViewMutable;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-import com.gtnewhorizons.angelica.glsm.recording.AccumulatedDraw;
-import org.joml.Matrix4f;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Accumulates geometry for a single vertex format during display list compilation.
- * Tracks merged ranges (same-transform draws combined) and per-draw ranges (1:1).
- */
-class FormatBuffer {
-    final CapturingTessellator.Flags flags;
-    final List<ModelQuadViewMutable> allQuads = new ArrayList<>();
-
-    // Merged ranges for optimized path (consecutive same-transform draws combined)
-    final List<DrawRange> mergedRanges = new ArrayList<>();
-
-    // Per-draw ranges for unoptimized path (1:1 with input draws)
-    final List<DrawRange> perDrawRanges = new ArrayList<>();
-
-    int currentVertexOffset = 0;
-
-    // Track the current range being built for merging consecutive same-transform draws
-    private int pendingStartVertex = -1;
-    private int pendingVertexCount = 0;
-    private Matrix4f pendingTransform = null;
-    private int pendingCommandIndex = -1;
-    private int pendingGeneration = -1;
-    private int pendingStateGen = -1;
-    // Track last restore data for merged draws (uses the LAST draw's data)
-    private AccumulatedDraw.RestoreData pendingRestoreData = null;
-
-    FormatBuffer(CapturingTessellator.Flags flags) {
-        this.flags = flags;
-    }
-
-    /** Add a draw, tracking both merged and per-draw ranges. */
-    void addDraw(AccumulatedDraw draw) {
-        final int vertexCount = draw.quads.size() * 4;  // 4 vertices per quad
-
-        // Always track per-draw range for unoptimized path (includes restoreData)
-        perDrawRanges.add(new DrawRange(
-            currentVertexOffset, vertexCount, draw.transform, draw.commandIndex, draw.restoreData
-        ));
-
-        // Merge logic for optimized path:
-        // - same matrixGeneration = same matrix transform context
-        // - same stateGeneration = no state commands (draw barriers) between draws
-        boolean canMerge = pendingGeneration != -1
-            && pendingGeneration == draw.matrixGeneration
-            && pendingStateGen == draw.stateGeneration;
-
-        if (canMerge) {
-            // Extend the pending range
-            pendingVertexCount += vertexCount;
-            // Update restoreData to the LAST draw's data (used after merged draw completes)
-            pendingRestoreData = draw.restoreData;
-        } else {
-            // Flush pending range if any
-            flushPendingRange();
-
-            // Start new pending range
-            pendingStartVertex = currentVertexOffset;
-            pendingVertexCount = vertexCount;
-            pendingTransform = new Matrix4f(draw.transform);
-            pendingCommandIndex = draw.commandIndex;
-            pendingGeneration = draw.matrixGeneration;
-            pendingStateGen = draw.stateGeneration;
-            pendingRestoreData = draw.restoreData;
-        }
-
-        allQuads.addAll(draw.quads);
-        currentVertexOffset += vertexCount;
-    }
-
-    private void flushPendingRange() {
-        if (pendingGeneration != -1) {
-            mergedRanges.add(new DrawRange(
-                pendingStartVertex, pendingVertexCount, pendingTransform, pendingCommandIndex, pendingRestoreData
-            ));
-            pendingTransform = null;
-            pendingGeneration = -1;
-            pendingStateGen = -1;
-            pendingRestoreData = null;
-        }
-    }
-
-    /** Compile accumulated quads into a VBO. */
-    CompiledFormatBuffer finish() {
-        // Flush any remaining pending range
-        flushPendingRange();
-
-        VertexBuffer vbo = DisplayListManager.compileQuads(allQuads, flags);
-        return new CompiledFormatBuffer(
-            vbo,
-            flags,
-            mergedRanges.toArray(new DrawRange[0]),
-            perDrawRanges.toArray(new DrawRange[0])
-        );
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/GLDebug.java

@@ -19,9 +19,6 @@ import org.lwjgl.opengl.GL43;
 import org.lwjgl.opengl.KHRDebug;
 import org.lwjgl.opengl.KHRDebugCallback;
 
-import java.io.PrintStream;
-import java.util.function.Consumer;
-
 import static com.gtnewhorizons.angelica.loading.AngelicaTweaker.LOGGER;
 import static org.lwjgl.opengl.ARBDebugOutput.glDebugMessageCallbackARB;
 
@@ -35,20 +32,9 @@ public final class GLDebug {
             LOGGER.warn("setupDebugMessageCallback called from non-main thread!");
             return 0;
         }
-        return setupDebugMessageCallback(System.err);
+        return setupDebugMessageCallbackImpl();
     }
 
-    private static void trace(Consumer<String> output) {
-		/*
-		 * We can not just use a fixed stacktrace element offset, because some methods
-		 * are intercepted and some are not. So, check the package name.
-		 */
-		StackTraceElement[] elems = filterStackTrace(new Throwable(), 4).getStackTrace();
-		for (StackTraceElement ste : elems) {
-			output.accept(ste.toString());
-		}
-	}
-
 	public static Throwable filterStackTrace(Throwable throwable, int offset) {
 		StackTraceElement[] elems = throwable.getStackTrace();
 		StackTraceElement[] filtered = new StackTraceElement[elems.length];
@@ -66,36 +52,48 @@ public final class GLDebug {
 		return throwable;
 	}
 
-	public static void printTrace(PrintStream stream) {
-		trace(new Consumer<String>() {
-			boolean first = true;
+	private static String buildStackTrace() {
+		StackTraceElement[] elems = filterStackTrace(new Throwable(), 4).getStackTrace();
+		StringBuilder sb = new StringBuilder();
+		for (StackTraceElement elem : elems) {
+			sb.append("\n\t").append(elem.toString());
+		}
+		return sb.toString();
+	}
 
-			public void accept(String str) {
-				if (first) {
-					printDetail(stream, "Stacktrace", str);
-					first = false;
-				} else {
-					printDetailLine(stream, "Stacktrace", str);
-				}
-			}
-		});
+	private static void logDebugMessage(int id, String source, String type, String severity, String message) {
+		String fullMessage = String.format("[GL] %s %s (0x%X) from %s: %s%s", severity, type, id, source, message, buildStackTrace());
+
+		if ("HIGH".equals(severity)) {
+			LOGGER.error(fullMessage);
+		} else if ("MEDIUM".equals(severity)) {
+			LOGGER.warn(fullMessage);
+		} else {
+			LOGGER.info(fullMessage);
+		}
+	}
+
+	private static void logDebugMessageAMD(int id, String category, String severity, String message) {
+		String fullMessage = String.format("[GL] %s %s (0x%X): %s%s", severity, category, id, message, buildStackTrace());
+
+		if ("HIGH".equals(severity)) {
+			LOGGER.error(fullMessage);
+		} else if ("MEDIUM".equals(severity)) {
+			LOGGER.warn(fullMessage);
+		} else {
+			LOGGER.info(fullMessage);
+		}
 	}
 
     /**
      * Sets up debug callbacks
      * @return 0 for failure, 1 for success, 2 for restart required.
      */
-    public static int setupDebugMessageCallback(PrintStream stream) {
+    private static int setupDebugMessageCallbackImpl() {
         if (GLStateManager.capabilities.OpenGL43 || GLStateManager.capabilities.GL_KHR_debug) {
             LOGGER.info("[GL] Using OpenGL 4.3 for error logging.");
-            KHRDebugCallback proc = new KHRDebugCallback((source, type, id, severity, message) -> {
-                stream.println("[LWJGL] OpenGL debug message");
-                printDetail(stream, "ID", String.format("0x%X", id));
-                printDetail(stream, "Source", getDebugSource(source));
-                printDetail(stream, "Type", getDebugType(type));
-                printDetail(stream, "Severity", getDebugSeverity(severity));
-                printDetail(stream, "Message", message);
-                printTrace(stream);
+            final KHRDebugCallback proc = new KHRDebugCallback((source, type, id, severity, message) -> {
+                logDebugMessage(id, getDebugSource(source), getDebugType(type), getDebugSeverity(severity), message);
             });
             GL43.glDebugMessageControl(GL11.GL_DONT_CARE, GL11.GL_DONT_CARE, GL43.GL_DEBUG_SEVERITY_HIGH, null, true);
             GL43.glDebugMessageControl(GL11.GL_DONT_CARE, GL11.GL_DONT_CARE, GL43.GL_DEBUG_SEVERITY_MEDIUM, null, false);
@@ -114,14 +112,8 @@ public final class GLDebug {
             return 1;
         } else if (GLStateManager.capabilities.GL_ARB_debug_output) {
             LOGGER.info("[GL] Using ARB_debug_output for error logging.");
-            ARBDebugOutputCallback proc = new ARBDebugOutputCallback((source, type, id, severity, message) -> {
-                stream.println("[LWJGL] ARB_debug_output message");
-                printDetail(stream, "ID", String.format("0x%X", id));
-                printDetail(stream, "Source", getSourceARB(source));
-                printDetail(stream, "Type", getTypeARB(type));
-                printDetail(stream, "Severity", getSeverityARB(severity));
-                printDetail(stream, "Message", message);
-                printTrace(stream);
+            final ARBDebugOutputCallback proc = new ARBDebugOutputCallback((source, type, id, severity, message) -> {
+                logDebugMessage(id, getSourceARB(source), getTypeARB(type), getSeverityARB(severity), message);
             });
             ARBDebugOutput.glDebugMessageControlARB(GL11.GL_DONT_CARE, GL11.GL_DONT_CARE, GL43.GL_DEBUG_SEVERITY_HIGH, null, true);
             ARBDebugOutput.glDebugMessageControlARB(GL11.GL_DONT_CARE, GL11.GL_DONT_CARE, GL43.GL_DEBUG_SEVERITY_MEDIUM, null, false);
@@ -134,13 +126,8 @@ public final class GLDebug {
             return 1;
         } else if (GLStateManager.capabilities.GL_AMD_debug_output) {
             LOGGER.info("[GL] Using AMD_debug_output for error logging.");
-            AMDDebugOutputCallback proc = new AMDDebugOutputCallback((id, category, severity, message) -> {
-                stream.println("[LWJGL] AMD_debug_output message");
-                printDetail(stream, "ID", String.format("0x%X", id));
-                printDetail(stream, "Category", getCategoryAMD(category));
-                printDetail(stream, "Severity", getSeverityAMD(severity));
-                printDetail(stream, "Message", message);
-                printTrace(stream);
+            final AMDDebugOutputCallback proc = new AMDDebugOutputCallback((id, category, severity, message) -> {
+                logDebugMessageAMD(id, getCategoryAMD(category), getSeverityAMD(severity), message);
             });
             AMDDebugOutput.glDebugMessageEnableAMD(0, GL43.GL_DEBUG_SEVERITY_HIGH, null, true);
             AMDDebugOutput.glDebugMessageEnableAMD(0, GL43.GL_DEBUG_SEVERITY_MEDIUM, null, false);
@@ -176,17 +163,6 @@ public final class GLDebug {
 		}
 	}
 
-	private static void printDetail(PrintStream stream, String type, String message) {
-		stream.printf("\t%s: %s\n", type, message);
-	}
-
-	private static void printDetailLine(PrintStream stream, String type, String message) {
-		stream.append("    ");
-		for (int i = 0; i < type.length(); i++) {
-			stream.append(" ");
-		}
-		stream.append(message).append("\n");
-	}
 
 	private static String getDebugSource(int source) {
         return switch (source) {
@@ -577,6 +553,57 @@ public final class GLDebug {
         };
 	}
 
+	public static String getFramebufferStatusName(int status) {
+        return switch (status) {
+            case GL30.GL_FRAMEBUFFER_COMPLETE -> "COMPLETE";
+            case GL30.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT -> "INCOMPLETE_ATTACHMENT";
+            case GL30.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT -> "INCOMPLETE_MISSING_ATTACHMENT";
+            case GL30.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER -> "INCOMPLETE_DRAW_BUFFER";
+            case GL30.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER -> "INCOMPLETE_READ_BUFFER";
+            case GL30.GL_FRAMEBUFFER_UNSUPPORTED -> "UNSUPPORTED";
+            case GL30.GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE -> "INCOMPLETE_MULTISAMPLE";
+            case 0 -> "NO_FRAMEBUFFER_BOUND";
+            default -> String.format("UNKNOWN(0x%X)", status);
+        };
+	}
+
+	public static String getInternalFormatName(int format) {
+        return switch (format) {
+            // Basic
+            case GL11.GL_RGBA -> "RGBA";
+            case GL11.GL_RGB -> "RGB";
+            // 8-bit normalized
+            case GL30.GL_R8 -> "R8";
+            case GL30.GL_RG8 -> "RG8";
+            case GL11.GL_RGB8 -> "RGB8";
+            case GL11.GL_RGBA8 -> "RGBA8";
+            // 8-bit signed normalized
+            case 0x8F94 -> "R8_SNORM";
+            case 0x8F95 -> "RG8_SNORM";
+            case 0x8F96 -> "RGB8_SNORM";
+            case 0x8F97 -> "RGBA8_SNORM";
+            // 16-bit normalized
+            case GL30.GL_R16 -> "R16";
+            case GL30.GL_RG16 -> "RG16";
+            case GL11.GL_RGB16 -> "RGB16";
+            case GL11.GL_RGBA16 -> "RGBA16";
+            // 16-bit float
+            case GL30.GL_R16F -> "R16F";
+            case GL30.GL_RG16F -> "RG16F";
+            case GL30.GL_RGB16F -> "RGB16F";
+            case GL30.GL_RGBA16F -> "RGBA16F";
+            // 32-bit float
+            case GL30.GL_R32F -> "R32F";
+            case GL30.GL_RG32F -> "RG32F";
+            case GL30.GL_RGB32F -> "RGB32F";
+            case GL30.GL_RGBA32F -> "RGBA32F";
+            // Packed
+            case GL30.GL_R11F_G11F_B10F -> "R11F_G11F_B10F";
+            case GL11.GL_RGB10_A2 -> "RGB10_A2";
+            default -> String.format("0x%X", format);
+        };
+	}
+
 	private static DebugState debugState;
 
     private interface DebugState {
@@ -593,6 +620,7 @@ public final class GLDebug {
 		private int depth = 0;
         private static final int maxDepth = GL11.glGetInteger(KHRDebug.GL_MAX_DEBUG_GROUP_STACK_DEPTH);
         private static final int maxNameLength = GL11.glGetInteger(KHRDebug.GL_MAX_LABEL_LENGTH);
+        private final String[] groupStack = new String[maxDepth + 1];
 
 		@Override
 		public void nameObject(int id, int object, String name) {
@@ -601,20 +629,28 @@ public final class GLDebug {
 
 		@Override
 		public void pushGroup(String name) {
-            depth++;
-            if (depth > maxDepth) {
-                throw new RuntimeException("Stack overflow");
+            if (depth + 1 > maxDepth) {
+                final StringBuilder sb = new StringBuilder();
+                sb.append("Debug group stack overflow (maxDepth=").append(maxDepth).append("), current stack:\n");
+                for (int i = 0; i < depth; i++) {
+                    sb.append("  [").append(i).append("] ").append(groupStack[i]).append('\n');
+                }
+                sb.append("  -> ").append(name).append(" (rejected)");
+                throw new RuntimeException(sb.toString());
             }
+            groupStack[depth] = name;
 			KHRDebug.glPushDebugGroup(KHRDebug.GL_DEBUG_SOURCE_APPLICATION, ID, name);
+            depth++;
 		}
 
 		@Override
 		public void popGroup() {
-            depth--;
-            if (depth < 0) {
+            if (depth - 1 < 0) {
                 throw new RuntimeException("Stack underflow");
             }
             KHRDebug.glPopDebugGroup();
+            depth--;
+            groupStack[depth] = null;
 		}
 
         @Override

src/main/java/com/gtnewhorizons/angelica/glsm/GlslTransformUtils.java

@@ -0,0 +1,111 @@
+package com.gtnewhorizons.angelica.glsm;
+
+import org.antlr.v4.runtime.tree.ParseTree;
+import org.antlr.v4.runtime.tree.TerminalNode;
+
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Shared GLSL shader transformation utilities.
+ */
+public class GlslTransformUtils {
+
+    private static final String RENAMED_PREFIX = "angelica_renamed_";
+
+    /** Texture function renames */
+    public static final Map<String, String> TEXTURE_RENAMES = Map.ofEntries(
+        Map.entry("texture2D", "texture"),
+        Map.entry("texture3D", "texture"),
+        Map.entry("texture2DLod", "textureLod"),
+        Map.entry("texture3DLod", "textureLod"),
+        Map.entry("texture2DProj", "textureProj"),
+        Map.entry("texture3DProj", "textureProj"),
+        Map.entry("texture2DGrad", "textureGrad"),
+        Map.entry("texture2DGradARB", "textureGrad"),
+        Map.entry("texture3DGrad", "textureGrad"),
+        Map.entry("texelFetch2D", "texelFetch"),
+        Map.entry("texelFetch3D", "texelFetch"),
+        Map.entry("textureSize2D", "textureSize")
+    );
+
+    private static final Pattern TEXTURE_PATTERN = Pattern.compile("\\btexture\\s*\\(|(\\btexture\\b)");
+
+    /** Reserved words added in later GLSL versions that may appear as identifiers in older shaders. */
+    private record ReservedWordRename(Pattern pattern, String replacement) {}
+    private static final Map<Integer, List<ReservedWordRename>> VERSIONED_RESERVED_WORDS = Map.of(
+        400, List.of(new ReservedWordRename(Pattern.compile("\\bsample\\b"), RENAMED_PREFIX + "sample"))
+    );
+
+    public static String replaceTexture(String input) {
+        final Matcher matcher = TEXTURE_PATTERN.matcher(input);
+        final StringBuilder builder = new StringBuilder();
+        while (matcher.find()) {
+            if (matcher.group(1) != null) {
+                matcher.appendReplacement(builder, RENAMED_PREFIX + "texture");
+            } else {
+                matcher.appendReplacement(builder, Matcher.quoteReplacement(matcher.group(0)));
+            }
+        }
+        matcher.appendTail(builder);
+        return builder.toString();
+    }
+
+    public static String renameReservedWords(String source, int targetVersion) {
+        for (var entry : VERSIONED_RESERVED_WORDS.entrySet()) {
+            if (targetVersion < entry.getKey()) {
+                for (var rename : entry.getValue()) {
+                    source = rename.pattern().matcher(source).replaceAll(rename.replacement());
+                }
+            }
+        }
+        return source;
+    }
+
+    public static String restoreReservedWords(String source) {
+        source = source.replace(RENAMED_PREFIX + "texture", "texture");
+        source = source.replace(RENAMED_PREFIX + "sample", "sample");
+        return source;
+    }
+
+    public static String getFormattedShader(ParseTree tree, String header) {
+        final StringBuilder sb = new StringBuilder(header + "\n");
+        final String[] tabHolder = {""};
+        getFormattedShader(tree, sb, tabHolder);
+        return sb.toString();
+    }
+
+    private static void getFormattedShader(ParseTree tree, StringBuilder stringBuilder, String[] tabHolder) {
+        if (tree instanceof TerminalNode) {
+            final String text = tree.getText();
+            if (text.equals("<EOF>")) {
+                return;
+            }
+            if (text.equals("#")) {
+                stringBuilder.append("\n#");
+                return;
+            }
+            stringBuilder.append(text);
+            if (text.equals("{")) {
+                stringBuilder.append(" \n\t");
+                tabHolder[0] = "\t";
+            }
+
+            if (text.equals("}")) {
+                if (stringBuilder.length() >= 2) {
+                    stringBuilder.deleteCharAt(stringBuilder.length() - 2);
+                }
+                tabHolder[0] = "";
+                stringBuilder.append(" \n");
+            } else {
+                stringBuilder.append(text.equals(";") ? " \n" + tabHolder[0] : " ");
+            }
+        } else {
+            for (int i = 0; i < tree.getChildCount(); ++i) {
+                getFormattedShader(tree.getChild(i), stringBuilder, tabHolder);
+            }
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/LineBuffer.java

@@ -1,134 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.gtnewhorizon.gtnhlib.client.renderer.vao.VAOManager;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-import com.gtnewhorizon.gtnhlib.client.renderer.vertex.DefaultVertexFormat;
-import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
-import com.gtnewhorizons.angelica.glsm.recording.AccumulatedLineDraw;
-import com.gtnewhorizons.angelica.glsm.recording.ImmediateModeRecorder;
-import org.joml.Matrix4f;
-import org.lwjgl.opengl.GL11;
-
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Accumulates line geometry during display list compilation.
- * All line draws are collected here, then compiled into a single VBO.
- * <p>
- * Lines all use the same format (POSITION_COLOR), so no format-based grouping needed.
- * <p>
- * Tracks two types of ranges:
- * <ul>
- *   <li><b>mergedRanges</b>: Consecutive same-transform draws merged for optimized path</li>
- *   <li><b>perDrawRanges</b>: One range per input draw for unoptimized path (1:1 with addDraw calls)</li>
- * </ul>
- */
-class LineBuffer {
-    final List<ImmediateModeRecorder.LineVertex> allVertices = new ArrayList<>();
-
-    // Merged ranges for optimized path (consecutive same-transform draws combined)
-    final List<DrawRange> mergedRanges = new ArrayList<>();
-
-    // Per-draw ranges for unoptimized path (1:1 with input draws)
-    final List<DrawRange> perDrawRanges = new ArrayList<>();
-
-    int currentVertexOffset = 0;
-
-    // Track the current range being built for merging consecutive same-transform draws
-    private int pendingStartVertex = -1;
-    private int pendingVertexCount = 0;
-    private Matrix4f pendingTransform = null;
-    private int pendingCommandIndex = -1;
-    private int pendingStateGen = -1;
-
-    /**
-     * Add a line draw to this buffer.
-     * Tracks both merged (for optimized) and per-draw (for unoptimized) ranges.
-     */
-    void addDraw(AccumulatedLineDraw draw) {
-        int vertexCount = draw.lines.size();  // Each LineVertex is one vertex, lines come in pairs
-
-        // Always track per-draw range for unoptimized path
-        perDrawRanges.add(new DrawRange(currentVertexOffset, vertexCount, draw.transform, draw.commandIndex));
-
-        // Merge logic for optimized path:
-        // - same transform
-        // - same stateGeneration = no state commands (draw barriers) between draws
-        boolean canMerge = pendingTransform != null
-            && pendingTransform.equals(draw.transform)
-            && pendingStateGen == draw.stateGeneration;
-
-        if (canMerge) {
-            // Extend the pending range
-            pendingVertexCount += vertexCount;
-        } else {
-            // Flush pending range if any
-            flushPendingRange();
-
-            // Start new pending range
-            pendingStartVertex = currentVertexOffset;
-            pendingVertexCount = vertexCount;
-            pendingTransform = new Matrix4f(draw.transform);
-            pendingCommandIndex = draw.commandIndex;
-            pendingStateGen = draw.stateGeneration;
-        }
-
-        allVertices.addAll(draw.lines);
-        currentVertexOffset += vertexCount;
-    }
-
-    private void flushPendingRange() {
-        if (pendingTransform != null) {
-            mergedRanges.add(new DrawRange(pendingStartVertex, pendingVertexCount, pendingTransform, pendingCommandIndex));
-            pendingTransform = null;
-            pendingStateGen = -1;
-        }
-    }
-
-    /**
-     * Compile all accumulated line vertices into a single VBO.
-     * @return The compiled buffer with VBO and both range types, or null if empty
-     */
-    CompiledLineBuffer finish() {
-        if (allVertices.isEmpty()) {
-            return null;
-        }
-
-        // Flush any remaining pending range
-        flushPendingRange();
-
-        VertexBuffer vbo = compileLinesToVBO(allVertices);
-        return new CompiledLineBuffer(
-            vbo,
-            mergedRanges.toArray(new DrawRange[0]),
-            perDrawRanges.toArray(new DrawRange[0])
-        );
-    }
-
-    /**
-     * Compile line vertices into a VertexBuffer (VAO or VBO).
-     * Lines use POSITION_COLOR format (x, y, z, color).
-     */
-    private static VertexBuffer compileLinesToVBO(List<ImmediateModeRecorder.LineVertex> lines) {
-        final VertexFormat format = DefaultVertexFormat.POSITION_COLOR;
-        final VertexBuffer vao = VAOManager.createVAO(format, GL11.GL_LINES);
-
-        // POSITION_COLOR format: 3 floats (12 bytes) + 4 bytes color = 16 bytes per vertex
-        final int vertexSize = format.getVertexSize();
-        final ByteBuffer buffer = org.lwjgl.BufferUtils.createByteBuffer(vertexSize * lines.size());
-
-        for (ImmediateModeRecorder.LineVertex v : lines) {
-            buffer.putFloat(v.x);
-            buffer.putFloat(v.y);
-            buffer.putFloat(v.z);
-            buffer.putInt(v.color);
-        }
-        buffer.flip();
-
-        vao.upload(buffer);
-
-        return vao;
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/OptimizedListResult.java

@@ -1,12 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-import com.gtnewhorizons.angelica.glsm.recording.commands.DisplayListCommand;
-
-/**
- * Result of building an optimized display list.
- * Contains both the commands and the shared VBOs that need lifecycle management.
- */
-@Desugar
-record OptimizedListResult(DisplayListCommand[] commands, VertexBuffer[] ownedVbos) {}

src/main/java/com/gtnewhorizons/angelica/glsm/QuadConverter.java

@@ -0,0 +1,294 @@
+package com.gtnewhorizons.angelica.glsm;
+
+import com.gtnewhorizons.angelica.glsm.states.VertexAttribState;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL15;
+
+import java.nio.ByteBuffer;
+import java.nio.IntBuffer;
+import java.nio.ShortBuffer;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAddress0;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAlloc;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memFree;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memGetByte;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memGetInt;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memGetShort;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memPutInt;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memPutShort;
+
+/**
+ * Shared quad-to-triangle EBO for core profile GL_QUADS emulation.
+ *
+ * <p>Maintains a single growable element buffer with pre-computed indices mapping
+ * GL_QUADS vertex order to GL_TRIANGLES: {@code (0,1,3, 1,2,3)} per quad.
+ * Uses {@code GL_LAST_VERTEX_CONVENTION} winding (Mesa {@code do_quad} LAST path)
+ * so both emitted triangles share the quad's provoking vertex (v3).
+ */
+public final class QuadConverter {
+    public static final int INDEX_TYPE = GL11.GL_UNSIGNED_INT;
+
+    private static int eboId;
+    private static int maxQuads;
+
+    /** Scratch EBO for converted quad-element draws (drawQuadElementsAsTriangles). */
+    private static int scratchEboId;
+    private static int scratchEboCapacity; // in bytes
+
+    private QuadConverter() {}
+
+    private static void ensureCapacity(int quadCount) {
+        if (quadCount <= maxQuads) return;
+
+        // Round up to power of 2 for amortized growth
+        int newMaxQuads = Math.max(256, maxQuads);
+        while (newMaxQuads < quadCount) {
+            newMaxQuads *= 2;
+        }
+
+        if (eboId == 0) {
+            eboId = GL15.glGenBuffers();
+        }
+
+        // Generate index data: 6 ints per quad
+        final ByteBuffer indexData = memAlloc(newMaxQuads * 6 * 4);
+        long ptr = memAddress0(indexData);
+        for (int i = 0; i < newMaxQuads; i++) {
+            final int base = i * 4;
+            // GL_LAST_VERTEX_CONVENTION: both triangles share v3 as provoking vertex
+            // Triangle 1: 0, 1, 3
+            memPutInt(ptr, base);
+            memPutInt(ptr + 4, base + 1);
+            memPutInt(ptr + 8, base + 3);
+            // Triangle 2: 1, 2, 3
+            memPutInt(ptr + 12, base + 1);
+            memPutInt(ptr + 16, base + 2);
+            memPutInt(ptr + 20, base + 3);
+            ptr += 24;
+        }
+
+        GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, eboId);
+        GL15.glBufferData(GL15.GL_ELEMENT_ARRAY_BUFFER, indexData, GL15.GL_STATIC_DRAW);
+
+        memFree(indexData);
+        maxQuads = newMaxQuads;
+    }
+
+    /**
+     * Convert a GL_QUADS glDrawArrays call to indexed GL_TRIANGLES.
+     * Binds the shared EBO to the current VAO and issues glDrawElements.
+     *
+     * @param first       first vertex index (must be aligned to quad boundary, i.e. multiple of 4)
+     * @param vertexCount number of vertices (must be multiple of 4)
+     */
+    public static void drawQuadsAsTriangles(int first, int vertexCount) {
+        assert first % 4 == 0 : "QuadConverter: first (" + first + ") must be a multiple of 4";
+        assert vertexCount % 4 == 0 : "QuadConverter: vertexCount (" + vertexCount + ") must be a multiple of 4";
+        final int quadCount = vertexCount / 4;
+        final int prevEbo = GLStateManager.getBoundEBO();
+        ensureCapacity(first / 4 + quadCount);
+        GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, eboId);
+        // Index offset: first vertex / 4 quads * 6 indices * 4 bytes per int
+        final long indexOffset = (long) (first / 4) * 6 * 4;
+        GL11.glDrawElements(GL11.GL_TRIANGLES, quadCount * 6, INDEX_TYPE, indexOffset);
+        GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, prevEbo);
+    }
+
+    /**
+     * Upload converted triangle indices to the scratch EBO and draw.
+     * Saves/restores the caller's EBO binding so subsequent indexed draws
+     * (or glGetBufferSubData reads) still see the original EBO.
+     *
+     * @param dst            off-heap buffer with triangle index data (freed by this method)
+     * @param triIndexCount  number of triangle indices
+     * @param indexType       GL_UNSIGNED_INT or GL_UNSIGNED_SHORT
+     * @param bytesPerIndex  bytes per index element
+     */
+    private static void uploadAndDraw(ByteBuffer dst, int triIndexCount, int indexType, int bytesPerIndex) {
+        final int needed = triIndexCount * bytesPerIndex;
+        final int prevEbo = GLStateManager.getBoundEBO();
+
+        if (scratchEboId == 0) {
+            scratchEboId = GL15.glGenBuffers();
+        }
+
+        GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, scratchEboId);
+
+        if (needed > scratchEboCapacity) {
+            // Power-of-2 growth — allocate full capacity, upload actual data
+            int newCap = Math.max(4096, scratchEboCapacity);
+            while (newCap < needed) newCap *= 2;
+            GL15.glBufferData(GL15.GL_ELEMENT_ARRAY_BUFFER, newCap, GL15.GL_STREAM_DRAW);
+            scratchEboCapacity = newCap;
+        }
+        GL15.glBufferSubData(GL15.GL_ELEMENT_ARRAY_BUFFER, 0, dst);
+
+        GL11.glDrawElements(GL11.GL_TRIANGLES, triIndexCount, indexType, 0L);
+
+        GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, prevEbo);
+        memFree(dst);
+    }
+
+    /**
+     * Convert an indexed GL_QUADS draw to GL_TRIANGLES by reading the source EBO,
+     * building a triangle index buffer, and issuing the converted draw.
+     *
+     * @param indexCount number of quad indices (must be multiple of 4)
+     * @param type       GL_UNSIGNED_INT, GL_UNSIGNED_SHORT, or GL_UNSIGNED_BYTE
+     * @param offset     byte offset into the currently bound EBO
+     */
+    public static void drawQuadElementsAsTriangles(int indexCount, int type, long offset) {
+        if (indexCount == 0) return;
+        assert indexCount % 4 == 0 : "QuadConverter: indexCount must be multiple of 4";
+        final int quadCount = indexCount / 4;
+        final int triIndexCount = quadCount * 6;
+
+        final int bytesPerIndex = VertexAttribState.Attrib.glTypeSizeBytes(type);
+
+        // Read source indices from caller's EBO
+        final ByteBuffer src = memAlloc(indexCount * bytesPerIndex);
+        GL15.glGetBufferSubData(GL15.GL_ELEMENT_ARRAY_BUFFER, offset, src);
+        final long srcAddr = memAddress0(src);
+
+        // Allocate output as GL_UNSIGNED_INT
+        final ByteBuffer dst = memAlloc(triIndexCount * 4);
+        final long dstAddr = memAddress0(dst);
+
+        for (int i = 0; i < quadCount; i++) {
+            final int a, b, c, d;
+            switch (type) {
+                case GL11.GL_UNSIGNED_INT -> {
+                    final long p = srcAddr + (long) i * 16;
+                    a = memGetInt(p); b = memGetInt(p + 4); c = memGetInt(p + 8); d = memGetInt(p + 12);
+                }
+                case GL11.GL_UNSIGNED_SHORT -> {
+                    final long p = srcAddr + (long) i * 8;
+                    a = memGetShort(p) & 0xFFFF; b = memGetShort(p + 2) & 0xFFFF;
+                    c = memGetShort(p + 4) & 0xFFFF; d = memGetShort(p + 6) & 0xFFFF;
+                }
+                default /* GL_UNSIGNED_BYTE */ -> {
+                    final long p = srcAddr + (long) i * 4;
+                    a = memGetByte(p) & 0xFF; b = memGetByte(p + 1) & 0xFF;
+                    c = memGetByte(p + 2) & 0xFF; d = memGetByte(p + 3) & 0xFF;
+                }
+            }
+            // GL_LAST_VERTEX_CONVENTION: (a,b,d), (b,c,d)
+            final long o = (long) i * 24;
+            memPutInt(dstAddr + o, a);
+            memPutInt(dstAddr + o + 4, b);
+            memPutInt(dstAddr + o + 8, d);
+            memPutInt(dstAddr + o + 12, b);
+            memPutInt(dstAddr + o + 16, c);
+            memPutInt(dstAddr + o + 20, d);
+        }
+
+        memFree(src);
+        uploadAndDraw(dst, triIndexCount, GL11.GL_UNSIGNED_INT, 4);
+    }
+
+    /**
+     * Convert a client-side IntBuffer of quad indices to triangles.
+     */
+    public static void drawQuadElementsAsTriangles(IntBuffer indices) {
+        final int indexCount = indices.remaining();
+        if (indexCount == 0) return;
+        assert indexCount % 4 == 0;
+        final int quadCount = indexCount / 4;
+        final int triIndexCount = quadCount * 6;
+
+        final ByteBuffer dst = memAlloc(triIndexCount * 4);
+        final long dstAddr = memAddress0(dst);
+        final int basePos = indices.position();
+
+        for (int i = 0; i < quadCount; i++) {
+            final int base = basePos + i * 4;
+            final int a = indices.get(base), b = indices.get(base + 1), c = indices.get(base + 2), d = indices.get(base + 3);
+            final long o = (long) i * 24;
+            memPutInt(dstAddr + o, a);     memPutInt(dstAddr + o + 4, b);  memPutInt(dstAddr + o + 8, d);
+            memPutInt(dstAddr + o + 12, b); memPutInt(dstAddr + o + 16, c); memPutInt(dstAddr + o + 20, d);
+        }
+
+        uploadAndDraw(dst, triIndexCount, GL11.GL_UNSIGNED_INT, 4);
+    }
+
+    /**
+     * Convert a client-side ShortBuffer of quad indices to triangles.
+     */
+    public static void drawQuadElementsAsTriangles(ShortBuffer indices) {
+        final int indexCount = indices.remaining();
+        if (indexCount == 0) return;
+        assert indexCount % 4 == 0;
+        final int quadCount = indexCount / 4;
+        final int triIndexCount = quadCount * 6;
+
+        final ByteBuffer dst = memAlloc(triIndexCount * 2);
+        final long dstAddr = memAddress0(dst);
+        final int basePos = indices.position();
+
+        for (int i = 0; i < quadCount; i++) {
+            final int base = basePos + i * 4;
+            final short a = indices.get(base), b = indices.get(base + 1), c = indices.get(base + 2), d = indices.get(base + 3);
+            final long o = (long) i * 12;
+            memPutShort(dstAddr + o, a);     memPutShort(dstAddr + o + 2, b);  memPutShort(dstAddr + o + 4, d);
+            memPutShort(dstAddr + o + 6, b); memPutShort(dstAddr + o + 8, c);  memPutShort(dstAddr + o + 10, d);
+        }
+
+        uploadAndDraw(dst, triIndexCount, GL11.GL_UNSIGNED_SHORT, 2);
+    }
+
+    /**
+     * Convert a client-side ByteBuffer of quad indices (type-agnostic) to triangles.
+     */
+    public static void drawQuadElementsAsTriangles(int count, int type, ByteBuffer indices) {
+        if (count == 0) return;
+        assert count % 4 == 0;
+        final int quadCount = count / 4;
+        final int triIndexCount = quadCount * 6;
+        final long srcAddr = memAddress0(indices) + indices.position();
+
+        final ByteBuffer dst = memAlloc(triIndexCount * 4);
+        final long dstAddr = memAddress0(dst);
+
+        for (int i = 0; i < quadCount; i++) {
+            final int a, b, c, d;
+            switch (type) {
+                case GL11.GL_UNSIGNED_INT -> {
+                    final long p = srcAddr + (long) i * 16;
+                    a = memGetInt(p); b = memGetInt(p + 4); c = memGetInt(p + 8); d = memGetInt(p + 12);
+                }
+                case GL11.GL_UNSIGNED_SHORT -> {
+                    final long p = srcAddr + (long) i * 8;
+                    a = memGetShort(p) & 0xFFFF; b = memGetShort(p + 2) & 0xFFFF;
+                    c = memGetShort(p + 4) & 0xFFFF; d = memGetShort(p + 6) & 0xFFFF;
+                }
+                case GL11.GL_UNSIGNED_BYTE -> {
+                    final long p = srcAddr + (long) i * 4;
+                    a = memGetByte(p) & 0xFF; b = memGetByte(p + 1) & 0xFF;
+                    c = memGetByte(p + 2) & 0xFF; d = memGetByte(p + 3) & 0xFF;
+                }
+                default -> { memFree(dst); return; }
+            }
+            final long o = (long) i * 24;
+            memPutInt(dstAddr + o, a);     memPutInt(dstAddr + o + 4, b);  memPutInt(dstAddr + o + 8, d);
+            memPutInt(dstAddr + o + 12, b); memPutInt(dstAddr + o + 16, c); memPutInt(dstAddr + o + 20, d);
+        }
+
+        uploadAndDraw(dst, triIndexCount, GL11.GL_UNSIGNED_INT, 4);
+    }
+
+    /**
+     * Clean up the shared EBO.
+     */
+    public static void destroy() {
+        if (eboId != 0) {
+            GL15.glDeleteBuffers(eboId);
+            eboId = 0;
+            maxQuads = 0;
+        }
+        if (scratchEboId != 0) {
+            GL15.glDeleteBuffers(scratchEboId);
+            scratchEboId = 0;
+            scratchEboCapacity = 0;
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/RenderSystem.java

@@ -1,23 +1,37 @@
 package com.gtnewhorizons.angelica.glsm;
 
-import com.gtnewhorizons.angelica.glsm.dsa.DSAARB;
 import com.gtnewhorizons.angelica.glsm.dsa.DSAAccess;
+import com.gtnewhorizons.angelica.glsm.dsa.DSAARB;
 import com.gtnewhorizons.angelica.glsm.dsa.DSACore;
+import com.gtnewhorizons.angelica.glsm.dsa.DSAEXT;
 import com.gtnewhorizons.angelica.glsm.dsa.DSAUnsupported;
+import com.gtnewhorizons.angelica.glsm.ffp.ShaderManager;
+import com.gtnewhorizons.angelica.glsm.texture.TextureInfoCache;
+import net.coderbot.iris.gl.shader.StandardMacros;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.Nullable;
 import org.joml.Matrix4f;
 import org.joml.Vector3i;
 import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.ARBBufferStorage;
+import org.lwjgl.opengl.ARBClearBufferObject;
+import org.lwjgl.opengl.ARBClearTexture;
+import org.lwjgl.opengl.ARBShaderImageLoadStore;
+import org.lwjgl.opengl.ARBShaderStorageBufferObject;
 import org.lwjgl.opengl.EXTShaderImageLoadStore;
 import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL12;
 import org.lwjgl.opengl.GL15;
 import org.lwjgl.opengl.GL20;
 import org.lwjgl.opengl.GL30;
+import org.lwjgl.opengl.GL32;
+import org.lwjgl.opengl.GL33;
 import org.lwjgl.opengl.GL40;
 import org.lwjgl.opengl.GL42;
 import org.lwjgl.opengl.GL43;
+import org.lwjgl.opengl.GL44;
+import org.lwjgl.opengl.NVXGpuMemoryInfo;
 
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
@@ -31,13 +45,26 @@ public class RenderSystem {
     private static final Logger LOGGER = LogManager.getLogger("RenderSystem");
 	private static DSAAccess dsaState;
 	private static boolean supportsCompute;
+	private static boolean supportsImageLoadStore;
+	private static boolean supportsSSBO;
+	private static boolean supportsBufferStorage;
+	private static boolean supportsClearTexture;
+	private static boolean supportsTesselation;
+	private static boolean supportsSamplerObjects;
+	private static int maxImageUnits;
+	private static int maxSSBOBindings;
+	private static int maxGlslVersion;
+	private static boolean supportsGpuShader4;
+
+	// Sampler object state tracking (null if unsupported)
+	private static int[] samplers;
 
     private RenderSystem() {}
 
 	public static void initRenderer() {
         try {
             if (GLStateManager.capabilities.OpenGL45) {
-                dsaState = new DSACore();
+                dsaState = (Runtime.version().feature() > 8 && GLStateManager.capabilities.GL_EXT_direct_state_access) ? new DSAEXT() : new DSACore();
                 LOGGER.info("OpenGL 4.5 detected, enabling DSA.");
             }
 
@@ -54,6 +81,59 @@ public class RenderSystem {
         }
 
 		supportsCompute = supportsCompute();
+		supportsTesselation = GLStateManager.capabilities.GL_ARB_tessellation_shader || GLStateManager.capabilities.OpenGL40;
+
+		supportsImageLoadStore = GLStateManager.capabilities.OpenGL42 || GLStateManager.capabilities.GL_ARB_shader_image_load_store || GLStateManager.capabilities.GL_EXT_shader_image_load_store;
+		supportsSSBO = GLStateManager.capabilities.OpenGL43 || GLStateManager.capabilities.GL_ARB_shader_storage_buffer_object;
+		supportsBufferStorage = GLStateManager.capabilities.OpenGL44 || GLStateManager.capabilities.GL_ARB_buffer_storage;
+		supportsClearTexture = GLStateManager.capabilities.OpenGL44 || GLStateManager.capabilities.GL_ARB_clear_texture;
+
+		// Cache maximum image units
+		if (supportsImageLoadStore) {
+			if (GLStateManager.capabilities.OpenGL42) {
+				maxImageUnits = GL11.glGetInteger(GL42.GL_MAX_IMAGE_UNITS);
+			} else if (GLStateManager.capabilities.GL_ARB_shader_image_load_store) {
+				maxImageUnits = GL11.glGetInteger(ARBShaderImageLoadStore.GL_MAX_IMAGE_UNITS);
+			} else {
+				maxImageUnits = GL11.glGetInteger(EXTShaderImageLoadStore.GL_MAX_IMAGE_UNITS_EXT);
+			}
+		} else {
+			maxImageUnits = 0;
+		}
+
+		// Cache maximum SSBO bindings
+		if (supportsSSBO) {
+			if (GLStateManager.capabilities.OpenGL43) {
+				maxSSBOBindings = GL11.glGetInteger(GL43.GL_MAX_SHADER_STORAGE_BUFFER_BINDINGS);
+			} else {
+				maxSSBOBindings = GL11.glGetInteger(ARBShaderStorageBufferObject.GL_MAX_SHADER_STORAGE_BUFFER_BINDINGS);
+			}
+		} else {
+			maxSSBOBindings = 0;
+		}
+
+		// Check for sampler objects support (GL 3.3+ or ARB extension)
+		supportsSamplerObjects = GLStateManager.capabilities.OpenGL33
+			|| GLStateManager.capabilities.GL_ARB_sampler_objects;
+		if (supportsSamplerObjects) {
+			samplers = new int[GL11.glGetInteger(GL20.GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS)];
+		}
+
+		maxGlslVersion = Integer.parseInt(StandardMacros.getGlVersion(GL20.GL_SHADING_LANGUAGE_VERSION));
+		supportsGpuShader4 = GLStateManager.capabilities.GL_EXT_gpu_shader4;
+
+		LOGGER.info("Max GLSL version: {}, GPU Shader4: {}", maxGlslVersion, supportsGpuShader4);
+		LOGGER.info("Image Load/Store: {}, Max Image Units: {}", supportsImageLoadStore, maxImageUnits);
+		LOGGER.info("SSBO: {}, Max SSBO Bindings: {}", supportsSSBO, maxSSBOBindings);
+		LOGGER.info("Buffer Storage: {}, Clear Texture: {}, Sampler Objects: {}", supportsBufferStorage, supportsClearTexture, supportsSamplerObjects);
+
+		if (GLStateManager.capabilities.OpenGL32) {
+			final int profileMask = GL11.glGetInteger(GL32.GL_CONTEXT_PROFILE_MASK);
+			if ((profileMask & GL32.GL_CONTEXT_CORE_PROFILE_BIT) != 0) {
+				LOGGER.info("GL 3.3 core profile detected, enabling FFP shader emulation.");
+				ShaderManager.getInstance().enable();
+			}
+		}
 	}
 
 	public static void generateMipmaps(int texture, int mipmapTarget) {
@@ -65,8 +145,11 @@ public class RenderSystem {
 	}
 
 	public static void texImage2D(int texture, int target, int level, int internalformat, int width, int height, int border, int format, int type, @Nullable ByteBuffer pixels) {
-		GLStateManager.glBindTexture(GL11.GL_TEXTURE_2D, texture);
-        GLStateManager.glTexImage2D(target, level, internalformat, width, height, border, format, type, pixels);
+		GLStateManager.glBindTexture(target, texture);
+		GL11.glTexImage2D(target, level, internalformat, width, height, border, format, type, pixels);
+		if (target == GL11.GL_TEXTURE_2D && level == 0) {
+			TextureInfoCache.INSTANCE.onTexImage2D(target, level, internalformat, width, height, border, format, type, pixels);
+		}
 	}
 
 	public static void uniformMatrix4fv(int location, boolean transpose, FloatBuffer matrix) {
@@ -147,6 +230,17 @@ public class RenderSystem {
 		dsaState.textureSubImage2D(texture, target, level, xoffset, yoffset, width, height, format, type, pixels);
 	}
 
+
+	public static void texImage1D(int texture, int target, int level, int internalformat, int width, int border, int format, int type, ByteBuffer pixels) {
+		GL11.glBindTexture(target, texture);
+		GL11.glTexImage1D(target, level, internalformat, width, border, format, type, pixels);
+	}
+
+	public static void texImage3D(int texture, int target, int level, int internalformat, int width, int height, int depth, int border, int format, int type, ByteBuffer pixels) {
+		GL11.glBindTexture(target, texture);
+		GL12.glTexImage3D(target, level, internalformat, width, height, depth, border, format, type, pixels);
+	}
+
     public static String getProgramInfoLog(int program) {
         return GL20.glGetProgramInfoLog(program, GL20.glGetProgrami(program, GL20.GL_INFO_LOG_LENGTH));
     }
@@ -208,13 +302,27 @@ public class RenderSystem {
 	}
 
 	public static int getMaxImageUnits() {
-		if (GLStateManager.capabilities.OpenGL42) {
-			return GL11.glGetInteger(GL42.GL_MAX_IMAGE_UNITS);
-		} else if (GLStateManager.capabilities.GL_EXT_shader_image_load_store) {
-			return GL11.glGetInteger(EXTShaderImageLoadStore.GL_MAX_IMAGE_UNITS_EXT);
-		} else {
-			return 0;
-		}
+		return maxImageUnits;
+	}
+
+	public static boolean supportsImageLoadStore() {
+		return supportsImageLoadStore;
+	}
+
+	public static boolean supportsSSBO() {
+		return supportsSSBO;
+	}
+
+	public static boolean supportsBufferStorage() {
+		return supportsBufferStorage;
+	}
+
+	public static boolean supportsClearTexture() {
+		return supportsClearTexture;
+	}
+
+	public static int getMaxSSBOBindings() {
+		return maxSSBOBindings;
 	}
 
 	public static void getProgramiv(int program, int value, IntBuffer storage) {
@@ -229,6 +337,14 @@ public class RenderSystem {
 		GL43.glDispatchCompute(workGroups.x, workGroups.y, workGroups.z);
 	}
 
+	public static void dispatchComputeIndirect(long offset) {
+		GL43.glDispatchComputeIndirect(offset);
+	}
+
+	public static void bindBuffer(int target, int buffer) {
+		GLStateManager.glBindBuffer(target, buffer);
+	}
+
 	public static void memoryBarrier(int barriers) {
 		if (supportsCompute) {
             GL42.glMemoryBarrier(barriers);
@@ -241,10 +357,12 @@ public class RenderSystem {
 
 	public static void disableBufferBlend(int buffer) {
 		GL30.glDisablei(GL11.GL_BLEND, buffer);
+		GLStateManager.getBlendMode().setUnknownState();
 	}
 
 	public static void enableBufferBlend(int buffer) {
 		GL30.glEnablei(GL11.GL_BLEND, buffer);
+		GLStateManager.getBlendMode().setUnknownState();
 	}
 
 	public static void blendFuncSeparatei(int buffer, int srcRGB, int dstRGB, int srcAlpha, int dstAlpha) {
@@ -255,6 +373,10 @@ public class RenderSystem {
 		dsaState.bindTextureToUnit(unit, texture);
 	}
 
+	public static void bindTextureToUnit(int target, int unit, int texture) {
+		dsaState.bindTextureToUnit(target, unit, texture);
+	}
+
     public static final FloatBuffer PROJECTION_MATRIX_BUFFER = BufferUtils.createFloatBuffer(16);
     public static void setupProjectionMatrix(Matrix4f matrix) {
         GLStateManager.glMatrixMode(GL11.GL_PROJECTION);
@@ -290,4 +412,122 @@ public class RenderSystem {
             return false;
         }
 	}
+
+	public static int createBuffers() {
+		return GL15.glGenBuffers();
+	}
+
+	public static void bindBufferBase(int target, int index, int buffer) {
+		GL30.glBindBufferBase(target, index, buffer);
+	}
+
+	public static void bufferStorage(int target, long size, int flags) {
+		if (GLStateManager.capabilities.OpenGL44) {
+			GL44.glBufferStorage(target, size, flags);
+		} else if (GLStateManager.capabilities.GL_ARB_buffer_storage) {
+			ARBBufferStorage.glBufferStorage(target, size, flags);
+		} else {
+			// Fallback: use mutable storage
+			GL15.glBufferData(target, size, GL15.GL_DYNAMIC_DRAW);
+		}
+	}
+
+	public static void clearBufferSubData(int target, int internalFormat, long offset, long size, int format, int type, int[] data) {
+		final ByteBuffer buf = BufferUtils.createByteBuffer(data.length * 4);
+		buf.asIntBuffer().put(data);
+		if (GLStateManager.capabilities.OpenGL43) {
+			GL43.glClearBufferSubData(target, internalFormat, offset, size, format, type, buf);
+		} else if (GLStateManager.capabilities.GL_ARB_clear_buffer_object) {
+			ARBClearBufferObject.glClearBufferSubData(target, internalFormat, offset, size, format, type, buf);
+		}
+	}
+
+	public static void deleteBuffers(int buffer) {
+		GL15.glDeleteBuffers(buffer);
+	}
+
+	public static long getVRAM() {
+		if (GLStateManager.capabilities.GL_NVX_gpu_memory_info) {
+			return GL11.glGetInteger(NVXGpuMemoryInfo.GL_GPU_MEMORY_INFO_CURRENT_AVAILABLE_VIDMEM_NVX) * 1024L;
+		} else {
+			// Default to 4GB if we can't query VRAM
+			return 4294967296L;
+		}
+	}
+
+	public static void clearTexImage(int texture, int target, int level, int format, int type) {
+		if (GLStateManager.capabilities.OpenGL44) {
+			GL44.glClearTexImage(texture, level, format, type, (ByteBuffer) null);
+		} else {
+			ARBClearTexture.glClearTexImage(texture, level, format, type, (ByteBuffer) null);
+		}
+	}
+
+	public static void textureStorage1D(int texture, int target, int levels, int internalFormat, int width) {
+		dsaState.textureStorage1D(texture, target, levels, internalFormat, width);
+	}
+
+	public static void textureStorage2D(int texture, int target, int levels, int internalFormat, int width, int height) {
+		dsaState.textureStorage2D(texture, target, levels, internalFormat, width, height);
+	}
+
+	public static void textureStorage3D(int texture, int target, int levels, int internalFormat, int width, int height, int depth) {
+		dsaState.textureStorage3D(texture, target, levels, internalFormat, width, height, depth);
+	}
+
+	public static int getMaxGlslVersion() {
+		return maxGlslVersion;
+	}
+
+	public static boolean supportsGpuShader4() {
+		return supportsGpuShader4;
+	}
+
+	public static boolean supportsSnormFormats() {
+		return GLStateManager.capabilities.OpenGL31;
+	}
+
+	public static boolean supportsPackedFloatRenderable() {
+		return GLStateManager.capabilities.OpenGL30 && maxGlslVersion >= 130;
+	}
+
+	public static boolean supportsTesselation() {
+		return supportsTesselation;
+	}
+
+	public static boolean supportsSamplerObjects() {
+		return supportsSamplerObjects;
+	}
+
+	public static int genSampler() {
+		if (!supportsSamplerObjects) return 0;
+		return GL33.glGenSamplers();
+	}
+
+	public static void destroySampler(int sampler) {
+		if (!supportsSamplerObjects || sampler == 0) return;
+		GL33.glDeleteSamplers(sampler);
+	}
+
+	public static void samplerParameteri(int sampler, int pname, int param) {
+		if (!supportsSamplerObjects || sampler == 0) return;
+		GL33.glSamplerParameteri(sampler, pname, param);
+	}
+
+	public static void bindSamplerToUnit(int unit, int sampler) {
+		if (!supportsSamplerObjects) return;
+		if (samplers[unit] == sampler) return;
+		GL33.glBindSampler(unit, sampler);
+		samplers[unit] = sampler;
+	}
+
+	public static void unbindAllSamplers() {
+		if (!supportsSamplerObjects) return;
+		for (int i = 0; i < samplers.length; i++) {
+			if (samplers[i] != 0) {
+				GL33.glBindSampler(i, 0);
+				samplers[i] = 0;
+			}
+		}
+	}
 }

src/main/java/com/gtnewhorizons/angelica/glsm/TessellatorPrimitiveBuffer.java

@@ -1,246 +0,0 @@
-package com.gtnewhorizons.angelica.glsm;
-
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.line.ModelLine;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.primitive.ModelPrimitiveView;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.tri.ModelTriangle;
-import com.gtnewhorizon.gtnhlib.client.renderer.vao.VAOManager;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
-import com.gtnewhorizons.angelica.glsm.recording.AccumulatedPrimitiveDraw;
-import org.joml.Matrix4f;
-import org.lwjgl.BufferUtils;
-import org.lwjgl.opengl.GL11;
-
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Accumulates tessellator primitives (lines, triangles) for a single vertex format during display list compilation.
- * Similar to FormatBuffer but handles ModelPrimitiveView instances instead of quads.
- * <p>
- * Unlike LineBuffer which handles ImmediateModeRecorder.LineVertex (fixed 16-byte: pos+color),
- * this handles ModelLine/ModelTriangle from the tessellator with format-optimized vertex size.
- * <p>
- * Primitives are separated by draw mode (GL_LINES, GL_TRIANGLES) into separate VBOs.
- */
-class TessellatorPrimitiveBuffer {
-    final CapturingTessellator.Flags flags;
-
-    // Accumulated primitives separated by type
-    final List<ModelLine> allLines = new ArrayList<>();
-    final List<ModelTriangle> allTriangles = new ArrayList<>();
-
-    // Ranges for lines
-    final List<DrawRange> lineMergedRanges = new ArrayList<>();
-    final List<DrawRange> linePerDrawRanges = new ArrayList<>();
-    int currentLineVertexOffset = 0;
-    private int pendingLineStartVertex = -1;
-    private int pendingLineVertexCount = 0;
-    private Matrix4f pendingLineTransform = null;
-    private int pendingLineCommandIndex = -1;
-    private int pendingLineStateGen = -1;
-
-    // Ranges for triangles
-    final List<DrawRange> triangleMergedRanges = new ArrayList<>();
-    final List<DrawRange> trianglePerDrawRanges = new ArrayList<>();
-    int currentTriangleVertexOffset = 0;
-    private int pendingTriangleStartVertex = -1;
-    private int pendingTriangleVertexCount = 0;
-    private Matrix4f pendingTriangleTransform = null;
-    private int pendingTriangleCommandIndex = -1;
-    private int pendingTriangleStateGen = -1;
-
-    TessellatorPrimitiveBuffer(CapturingTessellator.Flags flags) {
-        this.flags = flags;
-    }
-
-    /**
-     * Add a primitive draw to this buffer.
-     * Separates lines and triangles, tracking ranges for both merged and per-draw paths.
-     */
-    void addDraw(AccumulatedPrimitiveDraw draw) {
-        final List<ModelPrimitiveView> primitives = draw.primitives;
-        final int size = primitives.size();
-
-        // Single pass: count and collect primitives by type
-        int lineCount = 0;
-        int triangleCount = 0;
-        for (int i = 0; i < size; i++) {
-            final ModelPrimitiveView prim = primitives.get(i);
-            if (prim instanceof ModelLine ml) {
-                allLines.add(ml);
-                lineCount++;
-            } else if (prim instanceof ModelTriangle mt) {
-                allTriangles.add(mt);
-                triangleCount++;
-            }
-        }
-
-        // Process lines
-        if (lineCount > 0) {
-            final int lineVertexCount = lineCount * 2; // 2 vertices per line
-            linePerDrawRanges.add(new DrawRange(currentLineVertexOffset, lineVertexCount, draw.transform, draw.commandIndex));
-
-            // Merge logic for optimized path:
-            // - same transform
-            // - same stateGeneration = no state commands (draw barriers) between draws
-            boolean canMerge = pendingLineTransform != null
-                && pendingLineTransform.equals(draw.transform)
-                && pendingLineStateGen == draw.stateGeneration;
-
-            if (canMerge) {
-                pendingLineVertexCount += lineVertexCount;
-            } else {
-                flushPendingLineRange();
-                pendingLineStartVertex = currentLineVertexOffset;
-                pendingLineVertexCount = lineVertexCount;
-                pendingLineTransform = new Matrix4f(draw.transform);
-                pendingLineCommandIndex = draw.commandIndex;
-                pendingLineStateGen = draw.stateGeneration;
-            }
-            currentLineVertexOffset += lineVertexCount;
-        }
-
-        // Process triangles
-        if (triangleCount > 0) {
-            final int triangleVertexCount = triangleCount * 3; // 3 vertices per triangle
-            trianglePerDrawRanges.add(new DrawRange(currentTriangleVertexOffset, triangleVertexCount, draw.transform, draw.commandIndex));
-
-            // Merge logic for optimized path:
-            // - same transform
-            // - same stateGeneration = no state commands (draw barriers) between draws
-            boolean canMerge = pendingTriangleTransform != null
-                && pendingTriangleTransform.equals(draw.transform)
-                && pendingTriangleStateGen == draw.stateGeneration;
-
-            if (canMerge) {
-                pendingTriangleVertexCount += triangleVertexCount;
-            } else {
-                flushPendingTriangleRange();
-                pendingTriangleStartVertex = currentTriangleVertexOffset;
-                pendingTriangleVertexCount = triangleVertexCount;
-                pendingTriangleTransform = new Matrix4f(draw.transform);
-                pendingTriangleCommandIndex = draw.commandIndex;
-                pendingTriangleStateGen = draw.stateGeneration;
-            }
-            currentTriangleVertexOffset += triangleVertexCount;
-        }
-    }
-
-    private void flushPendingLineRange() {
-        if (pendingLineTransform != null) {
-            lineMergedRanges.add(new DrawRange(pendingLineStartVertex, pendingLineVertexCount, pendingLineTransform, pendingLineCommandIndex));
-            pendingLineTransform = null;
-            pendingLineStateGen = -1;
-        }
-    }
-
-    private void flushPendingTriangleRange() {
-        if (pendingTriangleTransform != null) {
-            triangleMergedRanges.add(new DrawRange(pendingTriangleStartVertex, pendingTriangleVertexCount, pendingTriangleTransform, pendingTriangleCommandIndex));
-            pendingTriangleTransform = null;
-            pendingTriangleStateGen = -1;
-        }
-    }
-
-    /**
-     * Compile all accumulated primitives into VBOs using optimal vertex format.
-     * @return The compiled buffers with separate VBOs for lines and triangles, or null if empty
-     */
-    CompiledPrimitiveBuffers finish() {
-        flushPendingLineRange();
-        flushPendingTriangleRange();
-
-        if (allLines.isEmpty() && allTriangles.isEmpty()) {
-            return null;
-        }
-
-        // Use optimal format based on flags (same logic as quads)
-        final VertexFormat format = DisplayListManager.selectOptimalFormat(flags);
-
-        final VertexBuffer lineVbo = allLines.isEmpty() ? null : compileLinesToVBO(format);
-        final VertexBuffer triangleVbo = allTriangles.isEmpty() ? null : compileTrianglesToVBO(format);
-
-        return new CompiledPrimitiveBuffers(
-            flags,
-            lineVbo,
-            lineMergedRanges.toArray(new DrawRange[0]),
-            linePerDrawRanges.toArray(new DrawRange[0]),
-            triangleVbo,
-            triangleMergedRanges.toArray(new DrawRange[0]),
-            trianglePerDrawRanges.toArray(new DrawRange[0])
-        );
-    }
-
-    private VertexBuffer compileLinesToVBO(VertexFormat format) {
-        final int vertexSize = format.getVertexSize();
-        final int size = allLines.size();
-        final ByteBuffer buffer = BufferUtils.createByteBuffer(vertexSize * size * 2);
-
-        for (int i = 0; i < size; i++) {
-            writePrimitiveToBuffer(allLines.get(i), buffer);
-        }
-        buffer.flip();
-
-        final VertexBuffer vbo = VAOManager.createVAO(format, GL11.GL_LINES);
-        vbo.upload(buffer);
-        return vbo;
-    }
-
-    private VertexBuffer compileTrianglesToVBO(VertexFormat format) {
-        final int vertexSize = format.getVertexSize();
-        final int size = allTriangles.size();
-        final ByteBuffer buffer = BufferUtils.createByteBuffer(vertexSize * size * 3);
-
-        for (int i = 0; i < size; i++) {
-            writePrimitiveToBuffer(allTriangles.get(i), buffer);
-        }
-        buffer.flip();
-
-        final VertexBuffer vbo = VAOManager.createVAO(format, GL11.GL_TRIANGLES);
-        vbo.upload(buffer);
-        return vbo;
-    }
-
-    /**
-     * Write a primitive's vertices to the buffer using the format specified by flags.
-     * Only writes attributes that are present in the format.
-     */
-    private void writePrimitiveToBuffer(ModelPrimitiveView prim, ByteBuffer buffer) {
-        final int vertexCount = prim.getVertexCount();
-        final boolean hasTexture = flags.hasTexture;
-        final boolean hasBrightness = flags.hasBrightness;
-        final boolean hasColor = flags.hasColor;
-        final boolean hasNormals = flags.hasNormals;
-
-        for (int i = 0; i < vertexCount; i++) {
-            // Position (always present) - 12 bytes
-            buffer.putFloat(prim.getX(i));
-            buffer.putFloat(prim.getY(i));
-            buffer.putFloat(prim.getZ(i));
-
-            // Color (4 bytes, ABGR) - if present
-            if (hasColor) {
-                buffer.putInt(prim.getColor(i));
-            }
-
-            // Texture (2 floats = 8 bytes) - if present
-            if (hasTexture) {
-                buffer.putFloat(prim.getTexU(i));
-                buffer.putFloat(prim.getTexV(i));
-            }
-
-            // Light/Brightness (4 bytes, packed) - if present
-            if (hasBrightness) {
-                buffer.putInt(prim.getLight(i));
-            }
-
-            // Normal (4 bytes, packed) - if present
-            if (hasNormals) {
-                buffer.putInt(prim.getForgeNormal(i));
-            }
-        }
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/compat/lwjgl/AngelicaCylinder.java

@@ -0,0 +1,142 @@
+package com.gtnewhorizons.angelica.glsm.compat.lwjgl;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.lwjgl.util.glu.Cylinder;
+
+import static org.lwjgl.opengl.GL11.GL_LINES;
+import static org.lwjgl.opengl.GL11.GL_LINE_LOOP;
+import static org.lwjgl.opengl.GL11.GL_POINTS;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
+import static org.lwjgl.util.glu.GLU.GLU_FILL;
+import static org.lwjgl.util.glu.GLU.GLU_INSIDE;
+import static org.lwjgl.util.glu.GLU.GLU_LINE;
+import static org.lwjgl.util.glu.GLU.GLU_POINT;
+import static org.lwjgl.util.glu.GLU.GLU_SILHOUETTE;
+
+/**
+ * Core-profile compatible replacement for {@link Cylinder}.
+ */
+@SuppressWarnings("unused")
+public class AngelicaCylinder extends Cylinder {
+
+    private static final float PI = (float) Math.PI;
+
+    private void emitNormal(float x, float y, float z) {
+        final float mag = (float) Math.sqrt(x * x + y * y + z * z);
+        if (mag > 0.00001F) {
+            x /= mag;
+            y /= mag;
+            z /= mag;
+        }
+        GLStateManager.glNormal3f(x, y, z);
+    }
+
+    private void emitTexCoord(float x, float y) {
+        if (super.textureFlag) GLStateManager.glTexCoord2f(x, y);
+    }
+
+    @Override
+    public void draw(float baseRadius, float topRadius, float height, int slices, int stacks) {
+        final float da, dr, dz, nz, nsign;
+        float r, x, y, z;
+
+        nsign = (super.orientation == GLU_INSIDE) ? -1.0f : 1.0f;
+
+        da = 2.0f * PI / slices;
+        dr = (topRadius - baseRadius) / stacks;
+        dz = height / stacks;
+        nz = (baseRadius - topRadius) / height;
+
+        if (super.drawStyle == GLU_POINT) {
+            GLStateManager.glBegin(GL_POINTS);
+            for (int i = 0; i < slices; i++) {
+                x = cos(i * da);
+                y = sin(i * da);
+                emitNormal(x * nsign, y * nsign, nz * nsign);
+
+                z = 0.0f;
+                r = baseRadius;
+                for (int j = 0; j <= stacks; j++) {
+                    GLStateManager.glVertex3f(x * r, y * r, z);
+                    z += dz;
+                    r += dr;
+                }
+            }
+            GLStateManager.glEnd();
+        } else if (super.drawStyle == GLU_LINE || super.drawStyle == GLU_SILHOUETTE) {
+            // Draw rings
+            if (super.drawStyle == GLU_LINE) {
+                z = 0.0f;
+                r = baseRadius;
+                for (int j = 0; j <= stacks; j++) {
+                    GLStateManager.glBegin(GL_LINE_LOOP);
+                    for (int i = 0; i < slices; i++) {
+                        x = cos(i * da);
+                        y = sin(i * da);
+                        emitNormal(x * nsign, y * nsign, nz * nsign);
+                        GLStateManager.glVertex3f(x * r, y * r, z);
+                    }
+                    GLStateManager.glEnd();
+                    z += dz;
+                    r += dr;
+                }
+            } else {
+                // draw one ring at each end
+                if (baseRadius != 0.0) {
+                    GLStateManager.glBegin(GL_LINE_LOOP);
+                    for (int i = 0; i < slices; i++) {
+                        x = cos(i * da);
+                        y = sin(i * da);
+                        emitNormal(x * nsign, y * nsign, nz * nsign);
+                        GLStateManager.glVertex3f(x * baseRadius, y * baseRadius, 0.0f);
+                    }
+                    GLStateManager.glEnd();
+                    GLStateManager.glBegin(GL_LINE_LOOP);
+                    for (int i = 0; i < slices; i++) {
+                        x = cos(i * da);
+                        y = sin(i * da);
+                        emitNormal(x * nsign, y * nsign, nz * nsign);
+                        GLStateManager.glVertex3f(x * topRadius, y * topRadius, height);
+                    }
+                    GLStateManager.glEnd();
+                }
+            }
+            // draw length lines
+            GLStateManager.glBegin(GL_LINES);
+            for (int i = 0; i < slices; i++) {
+                x = cos(i * da);
+                y = sin(i * da);
+                emitNormal(x * nsign, y * nsign, nz * nsign);
+                GLStateManager.glVertex3f(x * baseRadius, y * baseRadius, 0.0f);
+                GLStateManager.glVertex3f(x * topRadius, y * topRadius, height);
+            }
+            GLStateManager.glEnd();
+        } else if (super.drawStyle == GLU_FILL) {
+            final float ds = 1.0f / slices;
+            final float dt = 1.0f / stacks;
+            float t = 0.0f;
+            z = 0.0f;
+            r = baseRadius;
+            for (int j = 0; j < stacks; j++) {
+                float s = 0.0f;
+                GLStateManager.glBegin(GL_TRIANGLE_STRIP);
+                for (int i = 0; i <= slices; i++) {
+                    final float angle = (i == slices) ? 0.0f : i * da;
+                    x = sin(angle);
+                    y = cos(angle);
+                    emitNormal(x * nsign, y * nsign, nz * nsign);
+                    emitTexCoord(s, t);
+                    GLStateManager.glVertex3f(x * r, y * r, z);
+                    emitNormal(x * nsign, y * nsign, nz * nsign);
+                    emitTexCoord(s, t + dt);
+                    GLStateManager.glVertex3f(x * (r + dr), y * (r + dr), z + dz);
+                    s += ds;
+                }
+                GLStateManager.glEnd();
+                r += dr;
+                t += dt;
+                z += dz;
+            }
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/compat/lwjgl/AngelicaDisk.java

@@ -0,0 +1,134 @@
+package com.gtnewhorizons.angelica.glsm.compat.lwjgl;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.lwjgl.util.glu.Disk;
+
+import static org.lwjgl.opengl.GL11.GL_LINE_LOOP;
+import static org.lwjgl.opengl.GL11.GL_LINE_STRIP;
+import static org.lwjgl.opengl.GL11.GL_POINTS;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
+import static org.lwjgl.util.glu.GLU.GLU_FILL;
+import static org.lwjgl.util.glu.GLU.GLU_LINE;
+import static org.lwjgl.util.glu.GLU.GLU_NONE;
+import static org.lwjgl.util.glu.GLU.GLU_OUTSIDE;
+import static org.lwjgl.util.glu.GLU.GLU_POINT;
+import static org.lwjgl.util.glu.GLU.GLU_SILHOUETTE;
+
+/**
+ * Core-profile compatible replacement for {@link Disk}.
+ */
+@SuppressWarnings("unused")
+public class AngelicaDisk extends Disk {
+
+    private static final float PI = (float) Math.PI;
+
+    private void emitTexCoord(float x, float y) {
+        if (super.textureFlag) GLStateManager.glTexCoord2f(x, y);
+    }
+
+    @Override
+    public void draw(float innerRadius, float outerRadius, int slices, int loops) {
+        final float da, dr;
+
+        if (super.normals != GLU_NONE) {
+            GLStateManager.glNormal3f(0.0f, 0.0f, (super.orientation == GLU_OUTSIDE) ? 1.0f : -1.0f);
+        }
+
+        da = 2.0f * PI / slices;
+        dr = (outerRadius - innerRadius) / loops;
+
+        switch (super.drawStyle) {
+            case GLU_FILL -> {
+                final float dtc = 2.0f * outerRadius;
+                float sa, ca;
+                float r1 = innerRadius;
+                for (int l = 0; l < loops; l++) {
+                    final float r2 = r1 + dr;
+                    if (super.orientation == GLU_OUTSIDE) {
+                        GLStateManager.glBegin(GL_TRIANGLE_STRIP);
+                        for (int s = 0; s <= slices; s++) {
+                            final float a = (s == slices) ? 0.0f : s * da;
+                            sa = sin(a);
+                            ca = cos(a);
+                            emitTexCoord(0.5f + sa * r2 / dtc, 0.5f + ca * r2 / dtc);
+                            GLStateManager.glVertex2f(r2 * sa, r2 * ca);
+                            emitTexCoord(0.5f + sa * r1 / dtc, 0.5f + ca * r1 / dtc);
+                            GLStateManager.glVertex2f(r1 * sa, r1 * ca);
+                        }
+                        GLStateManager.glEnd();
+                    } else {
+                        GLStateManager.glBegin(GL_TRIANGLE_STRIP);
+                        for (int s = slices; s >= 0; s--) {
+                            final float a = (s == slices) ? 0.0f : s * da;
+                            sa = sin(a);
+                            ca = cos(a);
+                            emitTexCoord(0.5f - sa * r2 / dtc, 0.5f + ca * r2 / dtc);
+                            GLStateManager.glVertex2f(r2 * sa, r2 * ca);
+                            emitTexCoord(0.5f - sa * r1 / dtc, 0.5f + ca * r1 / dtc);
+                            GLStateManager.glVertex2f(r1 * sa, r1 * ca);
+                        }
+                        GLStateManager.glEnd();
+                    }
+                    r1 = r2;
+                }
+            }
+            case GLU_LINE -> {
+                /* draw loops */
+                for (int l = 0; l <= loops; l++) {
+                    final float r = innerRadius + l * dr;
+                    GLStateManager.glBegin(GL_LINE_LOOP);
+                    for (int s = 0; s < slices; s++) {
+                        final float a = s * da;
+                        GLStateManager.glVertex2f(r * sin(a), r * cos(a));
+                    }
+                    GLStateManager.glEnd();
+                }
+                /* draw spokes */
+                for (int s = 0; s < slices; s++) {
+                    final float a = s * da;
+                    final float x = sin(a);
+                    final float y = cos(a);
+                    GLStateManager.glBegin(GL_LINE_STRIP);
+                    for (int l = 0; l <= loops; l++) {
+                        final float r = innerRadius + l * dr;
+                        GLStateManager.glVertex2f(r * x, r * y);
+                    }
+                    GLStateManager.glEnd();
+                }
+            }
+            case GLU_POINT -> {
+                GLStateManager.glBegin(GL_POINTS);
+                for (int s = 0; s < slices; s++) {
+                    final float a = s * da;
+                    final float x = sin(a);
+                    final float y = cos(a);
+                    for (int l = 0; l <= loops; l++) {
+                        final float r = innerRadius * l * dr;
+                        GLStateManager.glVertex2f(r * x, r * y);
+                    }
+                }
+                GLStateManager.glEnd();
+            }
+            case GLU_SILHOUETTE -> {
+                if (innerRadius != 0.0) {
+                    GLStateManager.glBegin(GL_LINE_LOOP);
+                    for (float a = 0.0f; a < 2.0 * PI; a += da) {
+                        final float x = innerRadius * sin(a);
+                        final float y = innerRadius * cos(a);
+                        GLStateManager.glVertex2f(x, y);
+                    }
+                    GLStateManager.glEnd();
+                }
+                GLStateManager.glBegin(GL_LINE_LOOP);
+                for (float a = 0; a < 2.0f * PI; a += da) {
+                    final float x = outerRadius * sin(a);
+                    final float y = outerRadius * cos(a);
+                    GLStateManager.glVertex2f(x, y);
+                }
+                GLStateManager.glEnd();
+            }
+            default -> {
+            }
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/compat/lwjgl/AngelicaPartialDisk.java

@@ -0,0 +1,244 @@
+package com.gtnewhorizons.angelica.glsm.compat.lwjgl;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.lwjgl.util.glu.PartialDisk;
+
+import static com.gtnewhorizons.angelica.loading.AngelicaTweaker.LOGGER;
+import static org.lwjgl.opengl.GL11.GL_LINE_STRIP;
+import static org.lwjgl.opengl.GL11.GL_POINTS;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_FAN;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
+import static org.lwjgl.util.glu.GLU.GLU_FILL;
+import static org.lwjgl.util.glu.GLU.GLU_FLAT;
+import static org.lwjgl.util.glu.GLU.GLU_LINE;
+import static org.lwjgl.util.glu.GLU.GLU_OUTSIDE;
+import static org.lwjgl.util.glu.GLU.GLU_POINT;
+import static org.lwjgl.util.glu.GLU.GLU_SILHOUETTE;
+import static org.lwjgl.util.glu.GLU.GLU_SMOOTH;
+
+/**
+ * Core-profile compatible replacement for {@link PartialDisk}.
+ */
+@SuppressWarnings("unused")
+public class AngelicaPartialDisk extends PartialDisk {
+
+    private static final float PI = (float) Math.PI;
+    private static final int CACHE_SIZE = 240;
+    private final float[] sinCache = new float[CACHE_SIZE];
+    private final float[] cosCache = new float[CACHE_SIZE];
+
+    @Override
+    public void draw(float innerRadius, float outerRadius, int slices, int loops, float startAngle, float sweepAngle) {
+        final float deltaRadius, angleOffset;
+        float angle, sintemp, costemp, radiusLow, radiusHigh, texLow = 0, texHigh = 0;
+        final int slices2, finish;
+
+        if (slices >= CACHE_SIZE) slices = CACHE_SIZE - 1;
+        if (slices < 2 || loops < 1 || outerRadius <= 0.0f || innerRadius < 0.0f || innerRadius > outerRadius) {
+            LOGGER.warn("PartialDisk: GLU_INVALID_VALUE (slices={}, loops={}, innerRadius={}, outerRadius={})", slices, loops, innerRadius, outerRadius);
+            return;
+        }
+
+        if (sweepAngle < -360.0f) sweepAngle = 360.0f;
+        if (sweepAngle > 360.0f) sweepAngle = 360.0f;
+        if (sweepAngle < 0) {
+            startAngle += sweepAngle;
+            sweepAngle = -sweepAngle;
+        }
+
+        slices2 = (sweepAngle == 360.0f) ? slices : slices + 1;
+
+        /* Compute length (needed for normal calculations) */
+        deltaRadius = outerRadius - innerRadius;
+
+        angleOffset = startAngle / 180.0f * PI;
+        for (int i = 0; i <= slices; i++) {
+            angle = angleOffset + ((PI * sweepAngle) / 180.0f) * i / slices;
+            sinCache[i] = sin(angle);
+            cosCache[i] = cos(angle);
+        }
+
+        if (sweepAngle == 360.0f) {
+            sinCache[slices] = sinCache[0];
+            cosCache[slices] = cosCache[0];
+        }
+
+        switch (super.normals) {
+            case GLU_FLAT, GLU_SMOOTH -> GLStateManager.glNormal3f(0.0f, 0.0f, (super.orientation == GLU_OUTSIDE) ? 1.0f : -1.0f);
+            default -> {
+            }
+        }
+
+        switch (super.drawStyle) {
+            case GLU_FILL -> {
+                if (innerRadius == .0f) {
+                    finish = loops - 1;
+                    /* Triangle strip for inner polygons */
+                    GLStateManager.glBegin(GL_TRIANGLE_FAN);
+                    if (super.textureFlag) {
+                        GLStateManager.glTexCoord2f(0.5f, 0.5f);
+                    }
+                    GLStateManager.glVertex3f(0.0f, 0.0f, 0.0f);
+                    radiusLow = outerRadius - deltaRadius * ((float) (loops - 1) / loops);
+                    if (super.textureFlag) {
+                        texLow = radiusLow / outerRadius / 2;
+                    }
+
+                    if (super.orientation == GLU_OUTSIDE) {
+                        for (int i = slices; i >= 0; i--) {
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+                        }
+                    } else {
+                        for (int i = 0; i <= slices; i++) {
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+                        }
+                    }
+                    GLStateManager.glEnd();
+                } else {
+                    finish = loops;
+                }
+                for (int j = 0; j < finish; j++) {
+                    radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+                    radiusHigh = outerRadius - deltaRadius * ((float) (j + 1) / loops);
+                    if (super.textureFlag) {
+                        texLow = radiusLow / outerRadius / 2;
+                        texHigh = radiusHigh / outerRadius / 2;
+                    }
+
+                    GLStateManager.glBegin(GL_TRIANGLE_STRIP);
+                    for (int i = 0; i <= slices; i++) {
+                        if (super.orientation == GLU_OUTSIDE) {
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texHigh * sinCache[i] + 0.5f, texHigh * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusHigh * sinCache[i], radiusHigh * cosCache[i], 0.0f);
+                        } else {
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texHigh * sinCache[i] + 0.5f, texHigh * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusHigh * sinCache[i], radiusHigh * cosCache[i], 0.0f);
+
+                            if (super.textureFlag) {
+                                GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+                        }
+                    }
+                    GLStateManager.glEnd();
+                }
+            }
+            case GLU_POINT -> {
+                GLStateManager.glBegin(GL_POINTS);
+                for (int i = 0; i < slices2; i++) {
+                    sintemp = sinCache[i];
+                    costemp = cosCache[i];
+                    for (int j = 0; j <= loops; j++) {
+                        radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+
+                        if (super.textureFlag) {
+                            texLow = radiusLow / outerRadius / 2;
+
+                            GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                        }
+                        GLStateManager.glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0f);
+                    }
+                }
+                GLStateManager.glEnd();
+            }
+            case GLU_LINE -> {
+                if (innerRadius == outerRadius) {
+                    GLStateManager.glBegin(GL_LINE_STRIP);
+
+                    for (int i = 0; i <= slices; i++) {
+                        if (super.textureFlag) {
+                            GLStateManager.glTexCoord2f(sinCache[i] / 2 + 0.5f, cosCache[i] / 2 + 0.5f);
+                        }
+                        GLStateManager.glVertex3f(innerRadius * sinCache[i], innerRadius * cosCache[i], 0.0f);
+                    }
+                    GLStateManager.glEnd();
+                    break;
+                }
+                for (int j = 0; j <= loops; j++) {
+                    radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+                    if (super.textureFlag) {
+                        texLow = radiusLow / outerRadius / 2;
+                    }
+
+                    GLStateManager.glBegin(GL_LINE_STRIP);
+                    for (int i = 0; i <= slices; i++) {
+                        if (super.textureFlag) {
+                            GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                        }
+                        GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+                    }
+                    GLStateManager.glEnd();
+                }
+                for (int i = 0; i < slices2; i++) {
+                    sintemp = sinCache[i];
+                    costemp = cosCache[i];
+                    GLStateManager.glBegin(GL_LINE_STRIP);
+                    for (int j = 0; j <= loops; j++) {
+                        radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+                        if (super.textureFlag) {
+                            texLow = radiusLow / outerRadius / 2;
+                        }
+
+                        if (super.textureFlag) {
+                            GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                        }
+                        GLStateManager.glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0f);
+                    }
+                    GLStateManager.glEnd();
+                }
+            }
+            case GLU_SILHOUETTE -> {
+                if (sweepAngle < 360.0f) {
+                    for (int i = 0; i <= slices; i += slices) {
+                        sintemp = sinCache[i];
+                        costemp = cosCache[i];
+                        GLStateManager.glBegin(GL_LINE_STRIP);
+                        for (int j = 0; j <= loops; j++) {
+                            radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+
+                            if (super.textureFlag) {
+                                texLow = radiusLow / outerRadius / 2;
+                                GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                            }
+                            GLStateManager.glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0f);
+                        }
+                        GLStateManager.glEnd();
+                    }
+                }
+                for (int j = 0; j <= loops; j += loops) {
+                    radiusLow = outerRadius - deltaRadius * ((float) j / loops);
+                    if (super.textureFlag) {
+                        texLow = radiusLow / outerRadius / 2;
+                    }
+
+                    GLStateManager.glBegin(GL_LINE_STRIP);
+                    for (int i = 0; i <= slices; i++) {
+                        if (super.textureFlag) {
+                            GLStateManager.glTexCoord2f(texLow * sinCache[i] + 0.5f, texLow * cosCache[i] + 0.5f);
+                        }
+                        GLStateManager.glVertex3f(radiusLow * sinCache[i], radiusLow * cosCache[i], 0.0f);
+                    }
+                    GLStateManager.glEnd();
+                    if (innerRadius == outerRadius) break;
+                }
+            }
+            default -> {
+            }
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/compat/lwjgl/AngelicaSphere.java

@@ -0,0 +1,183 @@
+package com.gtnewhorizons.angelica.glsm.compat.lwjgl;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.lwjgl.util.glu.Sphere;
+
+import static org.lwjgl.opengl.GL11.GL_LINE_LOOP;
+import static org.lwjgl.opengl.GL11.GL_LINE_STRIP;
+import static org.lwjgl.opengl.GL11.GL_POINTS;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_FAN;
+import static org.lwjgl.opengl.GL11.GL_TRIANGLE_STRIP;
+import static org.lwjgl.util.glu.GLU.GLU_FILL;
+import static org.lwjgl.util.glu.GLU.GLU_INSIDE;
+import static org.lwjgl.util.glu.GLU.GLU_LINE;
+import static org.lwjgl.util.glu.GLU.GLU_NONE;
+import static org.lwjgl.util.glu.GLU.GLU_POINT;
+import static org.lwjgl.util.glu.GLU.GLU_SILHOUETTE;
+
+/**
+ * Core-profile compatible replacement for {@link Sphere}.
+ */
+@SuppressWarnings("unused")
+public class AngelicaSphere extends Sphere {
+
+    private static final float PI = (float) Math.PI;
+
+    private void emitNormal(float x, float y, float z) {
+        final float mag = (float) Math.sqrt(x * x + y * y + z * z);
+        if (mag > 0.00001F) {
+            x /= mag;
+            y /= mag;
+            z /= mag;
+        }
+        GLStateManager.glNormal3f(x, y, z);
+    }
+
+    private void emitTexCoord(float x, float y) {
+        if (super.textureFlag) GLStateManager.glTexCoord2f(x, y);
+    }
+
+    @Override
+    public void draw(float radius, int slices, int stacks) {
+        final float drho, dtheta, ds, dt, nsign;
+        float rho, theta, x, y, z, s, t;
+
+        final int imin, imax;
+        final boolean normals;
+
+        normals = super.normals != GLU_NONE;
+        nsign = (super.orientation == GLU_INSIDE) ? -1.0f : 1.0f;
+
+        drho = PI / stacks;
+        dtheta = 2.0f * PI / slices;
+
+        if (super.drawStyle == GLU_FILL) {
+            if (!super.textureFlag) {
+                // draw +Z end as a triangle fan
+                GLStateManager.glBegin(GL_TRIANGLE_FAN);
+                GLStateManager.glNormal3f(0.0f, 0.0f, 1.0f);
+                GLStateManager.glVertex3f(0.0f, 0.0f, nsign * radius);
+                for (int j = 0; j <= slices; j++) {
+                    theta = (j == slices) ? 0.0f : j * dtheta;
+                    x = -sin(theta) * sin(drho);
+                    y = cos(theta) * sin(drho);
+                    z = nsign * cos(drho);
+                    if (normals) {
+                        emitNormal(x * nsign, y * nsign, z * nsign);
+                    }
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+                GLStateManager.glEnd();
+            }
+
+            ds = 1.0f / slices;
+            dt = 1.0f / stacks;
+            t = 1.0f;
+            if (super.textureFlag) {
+                imin = 0;
+                imax = stacks;
+            } else {
+                imin = 1;
+                imax = stacks - 1;
+            }
+
+            // draw intermediate stacks as triangle strips (GL_QUAD_STRIP removed in core profile)
+            for (int i = imin; i < imax; i++) {
+                rho = i * drho;
+                GLStateManager.glBegin(GL_TRIANGLE_STRIP);
+                s = 0.0f;
+                for (int j = 0; j <= slices; j++) {
+                    theta = (j == slices) ? 0.0f : j * dtheta;
+                    x = -sin(theta) * sin(rho);
+                    y = cos(theta) * sin(rho);
+                    z = nsign * cos(rho);
+                    if (normals) {
+                        emitNormal(x * nsign, y * nsign, z * nsign);
+                    }
+                    emitTexCoord(s, t);
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                    x = -sin(theta) * sin(rho + drho);
+                    y = cos(theta) * sin(rho + drho);
+                    z = nsign * cos(rho + drho);
+                    if (normals) {
+                        emitNormal(x * nsign, y * nsign, z * nsign);
+                    }
+                    emitTexCoord(s, t - dt);
+                    s += ds;
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+                GLStateManager.glEnd();
+                t -= dt;
+            }
+
+            if (!super.textureFlag) {
+                // draw -Z end as a triangle fan
+                GLStateManager.glBegin(GL_TRIANGLE_FAN);
+                GLStateManager.glNormal3f(0.0f, 0.0f, -1.0f);
+                GLStateManager.glVertex3f(0.0f, 0.0f, -radius * nsign);
+                rho = PI - drho;
+                s = 1.0f;
+                for (int j = slices; j >= 0; j--) {
+                    theta = (j == slices) ? 0.0f : j * dtheta;
+                    x = -sin(theta) * sin(rho);
+                    y = cos(theta) * sin(rho);
+                    z = nsign * cos(rho);
+                    if (normals) emitNormal(x * nsign, y * nsign, z * nsign);
+                    s -= ds;
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+                GLStateManager.glEnd();
+            }
+        } else if (super.drawStyle == GLU_LINE || super.drawStyle == GLU_SILHOUETTE) {
+            // draw stack lines
+            for (int i = 1; i < stacks; i++) {
+                rho = i * drho;
+                GLStateManager.glBegin(GL_LINE_LOOP);
+                for (int j = 0; j < slices; j++) {
+                    theta = j * dtheta;
+                    x = cos(theta) * sin(rho);
+                    y = sin(theta) * sin(rho);
+                    z = cos(rho);
+                    if (normals) emitNormal(x * nsign, y * nsign, z * nsign);
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+                GLStateManager.glEnd();
+            }
+            // draw slice lines
+            for (int j = 0; j < slices; j++) {
+                theta = j * dtheta;
+                GLStateManager.glBegin(GL_LINE_STRIP);
+                for (int i = 0; i <= stacks; i++) {
+                    rho = i * drho;
+                    x = cos(theta) * sin(rho);
+                    y = sin(theta) * sin(rho);
+                    z = cos(rho);
+                    if (normals) emitNormal(x * nsign, y * nsign, z * nsign);
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+                GLStateManager.glEnd();
+            }
+        } else if (super.drawStyle == GLU_POINT) {
+            // top and bottom-most points
+            GLStateManager.glBegin(GL_POINTS);
+            if (normals) GLStateManager.glNormal3f(0.0f, 0.0f, nsign);
+            GLStateManager.glVertex3f(0.0f, 0.0f, radius);
+            if (normals) GLStateManager.glNormal3f(0.0f, 0.0f, -nsign);
+            GLStateManager.glVertex3f(0.0f, 0.0f, -radius);
+
+            // loop over stacks
+            for (int i = 1; i < stacks - 1; i++) {
+                rho = i * drho;
+                for (int j = 0; j < slices; j++) {
+                    theta = j * dtheta;
+                    x = cos(theta) * sin(rho);
+                    y = sin(theta) * sin(rho);
+                    z = cos(rho);
+                    if (normals) emitNormal(x * nsign, y * nsign, z * nsign);
+                    GLStateManager.glVertex3f(x * radius, y * radius, z * radius);
+                }
+            }
+            GLStateManager.glEnd();
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/dsa/DSAARB.java

@@ -40,6 +40,7 @@ public class DSAARB extends DSAUnsupported {
 
     @Override
     public void texParameteri(int texture, int target, int pname, int param) {
+        param = GLStateManager.remapTexClamp(pname, param);
         if(!GLStateManager.updateTexParameteriCache(target, texture, pname, param)) return;
 
         ARBDirectStateAccess.glTextureParameteri(texture, pname, param);
@@ -47,6 +48,7 @@ public class DSAARB extends DSAUnsupported {
 
     @Override
     public void texParameterf(int texture, int target, int pname, float param) {
+        param = GLStateManager.remapTexClamp(pname, param);
         if(!GLStateManager.updateTexParameterfCache(target, texture, pname, param)) return;
 
         ARBDirectStateAccess.glTextureParameterf(texture, pname, param);
@@ -54,6 +56,7 @@ public class DSAARB extends DSAUnsupported {
 
     @Override
     public void texParameteriv(int texture, int target, int pname, IntBuffer params) {
+        GLStateManager.remapTexClampBuffer(pname, params);
         ARBDirectStateAccess.glTextureParameter(texture, pname, params);
     }
 
@@ -94,6 +97,11 @@ public class DSAARB extends DSAUnsupported {
         }
     }
 
+    @Override
+    public void bindTextureToUnit(int target, int unit, int texture) {
+        bindTextureToUnit(unit, texture);
+    }
+
     @Override
     public int bufferStorage(int target, FloatBuffer data, int usage) {
         final int buffer = GL45.glCreateBuffers();
@@ -121,4 +129,19 @@ public class DSAARB extends DSAUnsupported {
     public int createTexture(int target) {
         return ARBDirectStateAccess.glCreateTextures(target);
     }
+
+    @Override
+    public void textureStorage1D(int texture, int target, int levels, int internalFormat, int width) {
+        ARBDirectStateAccess.glTextureStorage1D(texture, levels, internalFormat, width);
+    }
+
+    @Override
+    public void textureStorage2D(int texture, int target, int levels, int internalFormat, int width, int height) {
+        ARBDirectStateAccess.glTextureStorage2D(texture, levels, internalFormat, width, height);
+    }
+
+    @Override
+    public void textureStorage3D(int texture, int target, int levels, int internalFormat, int width, int height, int depth) {
+        ARBDirectStateAccess.glTextureStorage3D(texture, levels, internalFormat, width, height, depth);
+    }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/dsa/DSAAccess.java

@@ -28,6 +28,7 @@ public interface DSAAccess {
     void copyTexSubImage2D(int destTexture, int target, int i, int i1, int i2, int i3, int i4, int width, int height);
 
     void bindTextureToUnit(int unit, int texture);
+    void bindTextureToUnit(int target, int unit, int texture);
 
     int bufferStorage(int target, FloatBuffer data, int usage);
 
@@ -37,4 +38,9 @@ public interface DSAAccess {
 
     int createFramebuffer();
     int createTexture(int target);
+
+    // Texture storage methods for custom images
+    void textureStorage1D(int texture, int target, int levels, int internalFormat, int width);
+    void textureStorage2D(int texture, int target, int levels, int internalFormat, int width, int height);
+    void textureStorage3D(int texture, int target, int levels, int internalFormat, int width, int height, int depth);
 }

src/main/java/com/gtnewhorizons/angelica/glsm/dsa/DSAEXT.java

@@ -0,0 +1,18 @@
+package com.gtnewhorizons.angelica.glsm.dsa;
+
+import org.lwjgl.opengl.EXTDirectStateAccess;
+
+import java.nio.ByteBuffer;
+import java.nio.IntBuffer;
+
+public class DSAEXT extends DSACore {
+    @Override
+    public void textureImage2D(int texture, int target, int level, int internalformat, int width, int height, int border, int format, int type, ByteBuffer pixels) {
+        EXTDirectStateAccess.glTextureImage2DEXT(texture, target, level, internalformat, width, height, border, format, type, pixels);
+    }
+
+    @Override
+    public void textureImage2D(int texture, int target, int level, int internalformat, int width, int height, int border, int format, int type, IntBuffer pixels) {
+        EXTDirectStateAccess.glTextureImage2DEXT(texture, target, level, internalformat, width, height, border, format, type, pixels);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/dsa/DSAUnsupported.java

@@ -2,12 +2,14 @@ package com.gtnewhorizons.angelica.glsm.dsa;
 
 import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import com.gtnewhorizons.angelica.glsm.RenderSystem;
-import net.minecraft.client.renderer.OpenGlHelper;
 import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL12;
 import org.lwjgl.opengl.GL13;
 import org.lwjgl.opengl.GL15;
 import org.lwjgl.opengl.GL20;
 import org.lwjgl.opengl.GL30;
+import org.lwjgl.opengl.GL31;
+import org.lwjgl.opengl.GL42;
 
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
@@ -74,13 +76,13 @@ public class DSAUnsupported implements DSAAccess {
 
     @Override
     public void readBuffer(int framebuffer, int buffer) {
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(GL30.GL_FRAMEBUFFER, framebuffer);
+        GLStateManager.glBindFramebuffer(GL30.GL_FRAMEBUFFER, framebuffer);
         GL11.glReadBuffer(buffer);
     }
 
     @Override
     public void drawBuffers(int framebuffer, IntBuffer buffers) {
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(GL30.GL_FRAMEBUFFER, framebuffer);
+        GLStateManager.glBindFramebuffer(GL30.GL_FRAMEBUFFER, framebuffer);
         GL20.glDrawBuffers(buffers);
     }
 
@@ -113,12 +115,18 @@ public class DSAUnsupported implements DSAAccess {
         GLStateManager.glBindTexture(GL11.GL_TEXTURE_2D, texture);
     }
 
+    @Override
+    public void bindTextureToUnit(int target, int unit, int texture) {
+        GLStateManager.glActiveTexture(GL13.GL_TEXTURE0 + unit);
+        GLStateManager.glBindTexture(target, texture);
+    }
+
     @Override
     public int bufferStorage(int target, FloatBuffer data, int usage) {
         final int buffer = GL15.glGenBuffers();
-        GL15.glBindBuffer(target, buffer);
+        GLStateManager.glBindBuffer(target, buffer);
         RenderSystem.bufferData(target, data, usage);
-        GL15.glBindBuffer(target, 0);
+        GLStateManager.glBindBuffer(target, 0);
 
         return buffer;
     }
@@ -126,21 +134,21 @@ public class DSAUnsupported implements DSAAccess {
     @Override
     public void blitFramebuffer(int source, int dest, int offsetX, int offsetY, int width, int height, int offsetX2, int offsetY2, int width2, int height2,
         int bufferChoice, int filter) {
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(GL30.GL_READ_FRAMEBUFFER, source);
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(GL30.GL_DRAW_FRAMEBUFFER, dest);
+        GLStateManager.glBindFramebuffer(GL30.GL_READ_FRAMEBUFFER, source);
+        GLStateManager.glBindFramebuffer(GL30.GL_DRAW_FRAMEBUFFER, dest);
         GL30.glBlitFramebuffer(offsetX, offsetY, width, height, offsetX2, offsetY2, width2, height2, bufferChoice, filter);
     }
 
     @Override
     public void framebufferTexture2D(int fb, int fbtarget, int attachment, int target, int texture, int levels) {
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(fbtarget, fb);
+        GLStateManager.glBindFramebuffer(fbtarget, fb);
         GL30.glFramebufferTexture2D(fbtarget, attachment, target, texture, levels);
     }
 
     @Override
     public int createFramebuffer() {
-        final int framebuffer = OpenGlHelper.func_153165_e/*glGenFramebuffers*/();
-        OpenGlHelper.func_153171_g/*glBindFramebuffer*/(GL30.GL_FRAMEBUFFER, framebuffer);
+        final int framebuffer = GLStateManager.glGenFramebuffers();
+        GLStateManager.glBindFramebuffer(GL30.GL_FRAMEBUFFER, framebuffer);
         return framebuffer;
     }
 
@@ -150,4 +158,28 @@ public class DSAUnsupported implements DSAAccess {
         GLStateManager.glBindTexture(GL11.GL_TEXTURE_2D, texture);
         return texture;
     }
+
+    @Override
+    public void textureStorage1D(int texture, int target, int levels, int internalFormat, int width) {
+        final int previous = GL11.glGetInteger(GL11.GL_TEXTURE_BINDING_1D);
+        GL11.glBindTexture(target, texture);
+        GL42.glTexStorage1D(target, levels, internalFormat, width);
+        GL11.glBindTexture(target, previous);
+    }
+
+    @Override
+    public void textureStorage2D(int texture, int target, int levels, int internalFormat, int width, int height) {
+        final int previous = (target == GL11.GL_TEXTURE_2D) ? GLStateManager.getBoundTextureForServerState() : GL11.glGetInteger(GL31.GL_TEXTURE_BINDING_RECTANGLE);
+        GL11.glBindTexture(target, texture);
+        GL42.glTexStorage2D(target, levels, internalFormat, width, height);
+        GL11.glBindTexture(target, previous);
+    }
+
+    @Override
+    public void textureStorage3D(int texture, int target, int levels, int internalFormat, int width, int height, int depth) {
+        final int previous = GL11.glGetInteger(GL12.GL_TEXTURE_BINDING_3D);
+        GL11.glBindTexture(target, texture);
+        GL42.glTexStorage3D(target, levels, internalFormat, width, height, depth);
+        GL11.glBindTexture(target, previous);
+    }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/DeferredBatchTessellator.java

@@ -0,0 +1,92 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.github.bsideup.jabel.Desugar;
+import com.gtnewhorizon.gtnhlib.client.renderer.DirectTessellator;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFlags;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import net.minecraft.client.renderer.Tessellator;
+import org.joml.Matrix4f;
+import org.joml.Matrix4fc;
+import org.joml.Vector3f;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memCopy;
+
+/**
+ * DirectTessellator subclass for deferred particle batching. Accumulates vertex data from
+ * multiple interceptDraw() calls, recording per-draw metadata as {@link DrawRange} entries.
+ * Computes a delta modelview matrix at each intercept to pre-transform vertices.
+ */
+class DeferredBatchTessellator extends DirectTessellator {
+
+    @Desugar
+    record DrawRange(long stateKey, int byteOffset, int byteLength, int vertexCount, int drawMode, int flags) {}
+
+    private final List<DrawRange> ranges = new ArrayList<>();
+    private final Matrix4f defaultModelview = new Matrix4f();
+    private final Matrix4f defaultModelviewInverse = new Matrix4f();
+    private final Matrix4f deltaMatrix = new Matrix4f(); // reusable scratch
+    private final Vector3f scratch = new Vector3f();
+    private Matrix4fc currentTransform;
+
+    DeferredBatchTessellator(ByteBuffer buffer) {
+        super(buffer, false); // deleteAfter=false: keep buffer across resets for reuse
+    }
+
+    @Override
+    protected long writeVertexData(VertexFormat format, int[] rawBuffer, int rawBufferIndex) {
+        if (currentTransform != null) {
+            return format.writeToBuffer0(writePtr, rawBuffer, rawBufferIndex, currentTransform, scratch);
+        }
+        return super.writeVertexData(format, rawBuffer, rawBufferIndex);
+    }
+
+    /** Snapshot the current modelview as the "default" for this bracket. */
+    void snapshotDefaultModelview() {
+        defaultModelview.set(GLStateManager.getModelViewMatrix());
+        defaultModelview.invert(defaultModelviewInverse);
+    }
+
+    @Override
+    protected int interceptDraw(Tessellator tess) {
+        // Compute delta: if current MV differs from default, pre-transform vertices
+        final Matrix4f currentMV = GLStateManager.getModelViewMatrix();
+        if (!currentMV.equals(defaultModelview)) {
+            defaultModelviewInverse.mul(currentMV, deltaMatrix);
+            this.currentTransform = deltaMatrix;
+        } else {
+            this.currentTransform = null;
+        }
+
+        final int byteOffsetBefore = bufferLimit();
+        final int vertCount = tess.vertexCount;
+        final int drawMode = tess.drawMode;
+        final int flags = VertexFlags.convertToFlags(tess.hasTexture, tess.hasColor, tess.hasNormals, tess.hasBrightness);
+        final long stateKey = DeferredDrawBatcher.captureStateKey();
+
+        final int result = super.interceptDraw(tess); // repacks int[] → ByteBuffer + transforms if vertexTransform set
+
+        final int byteOffsetAfter = bufferLimit();
+        ranges.add(new DrawRange(stateKey, byteOffsetBefore, byteOffsetAfter - byteOffsetBefore, vertCount, drawMode, flags));
+        this.currentTransform = null; // clear for next draw
+        return result;
+    }
+
+    List<DrawRange> getRanges() { return ranges; }
+
+    void clearRanges() { ranges.clear(); }
+
+    void copyRange(int byteOffset, int byteLength, long destAddress) {
+        memCopy(startPtr + byteOffset, destAddress, byteLength);
+    }
+
+    @Override
+    protected void onRemovedFromStack() {
+        clearRanges();
+        super.onRemovedFromStack(); // calls reset(), keeps baseBuffer (deleteAfter=false)
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/DeferredDrawBatcher.java

@@ -0,0 +1,173 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.TessellatorManager;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import lombok.Getter;
+import org.lwjgl.opengl.GL11;
+
+import java.util.Comparator;
+import java.util.List;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAlloc;
+
+/**
+ * Deferred draw batching coordinator. During rendering regions (e.g. particles),
+ * intercepts tessellator.draw() calls via DirectTessellator, captures pre-packed vertex data
+ * + GL state, then flushes all captured batches sorted by state key.
+ * <p>
+ * Vertices are pre-transformed at capture time.
+ */
+public class DeferredDrawBatcher {
+
+    private static final int INITIAL_BUFFER_SIZE = 64 * 1024;
+
+    @Getter private static boolean active = false;
+    private static DeferredBatchTessellator batchTessellator;
+
+    private DeferredDrawBatcher() {}
+
+    /**
+     * Begin deferred capture mode. Called after startDrawingQuads().
+     * Pushes a DeferredBatchTessellator onto the DirectTessellator stack so that
+     * subsequent tessellator.draw() calls are intercepted and accumulated.
+     */
+    public static void enter() {
+        active = true;
+        if (batchTessellator == null) {
+            batchTessellator = new DeferredBatchTessellator(memAlloc(INITIAL_BUFFER_SIZE));
+        }
+        batchTessellator.clearRanges();
+        batchTessellator.snapshotDefaultModelview();
+        TessellatorManager.startCapturingDirect(batchTessellator);
+    }
+
+    /**
+     * Exit deferred mode and flush all captured batches. Groups entries by state key
+     * and vertex format, issues one draw per unique group. Restores the GL state that
+     * was active for the last group so vanilla sees consistent state.
+     */
+    public static void exitAndFlush() {
+        active = false;
+        final List<DeferredBatchTessellator.DrawRange> ranges = batchTessellator.getRanges();
+
+        if (!ranges.isEmpty()) {
+            ranges.sort(Comparator.comparingLong(DeferredBatchTessellator.DrawRange::stateKey));
+            flushSorted(ranges);
+        }
+
+        TessellatorManager.stopCapturingDirect();
+    }
+
+    private static void flushSorted(List<DeferredBatchTessellator.DrawRange> ranges) {
+        long currentKey = ranges.get(0).stateKey();
+        int groupStart = 0;
+
+        for (int i = 0; i <= ranges.size(); i++) {
+            final boolean endOfList = (i == ranges.size());
+            final boolean keyChanged = !endOfList && ranges.get(i).stateKey() != currentKey;
+
+            if (endOfList || keyChanged) {
+                applyStateKey(currentKey);
+                flushGroup(ranges, groupStart, i);
+
+                if (!endOfList) {
+                    currentKey = ranges.get(i).stateKey();
+                    groupStart = i;
+                }
+            }
+        }
+    }
+
+    /**
+     * Flush a group of ranges sharing the same state key.
+     * Subgroups by (drawMode, format flags) since those must match for merged draws.
+     */
+    private static void flushGroup(List<DeferredBatchTessellator.DrawRange> ranges, int from, int to) {
+        int i = from;
+        while (i < to) {
+            final DeferredBatchTessellator.DrawRange first = ranges.get(i);
+            final int drawMode = first.drawMode();
+            final int flags = first.flags();
+
+            int totalBytes = 0;
+            int totalVertices = 0;
+            int subEnd = i;
+
+            while (subEnd < to) {
+                final DeferredBatchTessellator.DrawRange e = ranges.get(subEnd);
+                if (e.drawMode() != drawMode || e.flags() != flags) break;
+                totalBytes += e.byteLength();
+                totalVertices += e.vertexCount();
+                subEnd++;
+            }
+
+            TessellatorStreamingDrawer.drawPackedBatch(
+                batchTessellator, ranges, i, subEnd, totalBytes, totalVertices, drawMode, flags);
+
+            i = subEnd;
+        }
+    }
+
+    /**
+     * Pack current GLSM state into a long key for grouping.
+     * Layout: [tex1En:1][tex0En:1][textureId:20][srcRgb:12][dstRgb:12][blendEnabled:1][depthMask:1] = 48 bits
+     * GL blend constants (e.g. GL_SRC_ALPHA=0x0302) need 12 bits.
+     *
+     * NOT captured (uniform within a particle layer bracket — set once before startDrawingQuads,
+     * not changed by individual particles):
+     * - depth test enable (always GL_LEQUAL for particles)
+     * - alpha test func/ref (set per-layer, not per-particle)
+     * - separate blend alpha factors (srcAlpha/dstAlpha) — particles use glBlendFunc not glBlendFuncSeparate
+     * - fog state (mode, color, start/end — constant for the frame)
+     */
+    static long captureStateKey() {
+        final int textureId = GLStateManager.getTextures().getTextureUnitBindings(0).getBinding();
+        final int srcRgb = GLStateManager.getBlendState().getSrcRgb();
+        final int dstRgb = GLStateManager.getBlendState().getDstRgb();
+        final boolean blendEnabled = GLStateManager.getBlendMode().isEnabled();
+        final boolean depthMask = GLStateManager.getDepthState().isEnabled();
+        final boolean tex0Enabled = GLStateManager.getTextures().getTextureUnitStates(0).isEnabled();
+        final boolean tex1Enabled = GLStateManager.getTextures().getTextureUnitStates(1).isEnabled();
+
+        return packStateKey(textureId, srcRgb, dstRgb, blendEnabled, depthMask, tex0Enabled, tex1Enabled);
+    }
+
+    static long packStateKey(int textureId, int srcRgb, int dstRgb, boolean blendEnabled, boolean depthMask, boolean tex0Enabled, boolean tex1Enabled) {
+        return ((long) (textureId & 0xFFFFF) << 26)
+            | ((long) (srcRgb & 0xFFF) << 14)
+            | ((long) (dstRgb & 0xFFF) << 2)
+            | (blendEnabled ? 2L : 0L)
+            | (depthMask ? 1L : 0L)
+            | (tex0Enabled ? (1L << 46) : 0L)
+            | (tex1Enabled ? (1L << 47) : 0L);
+    }
+
+    static int unpackTextureId(long key) { return (int) ((key >> 26) & 0xFFFFF); }
+    static int unpackSrcRgb(long key) { return (int) ((key >> 14) & 0xFFF); }
+    static int unpackDstRgb(long key) { return (int) ((key >> 2) & 0xFFF); }
+    static boolean unpackBlendEnabled(long key) { return (key & 2L) != 0; }
+    static boolean unpackDepthMask(long key) { return (key & 1L) != 0; }
+    static boolean unpackTex0Enabled(long key) { return (key & (1L << 46)) != 0; }
+    static boolean unpackTex1Enabled(long key) { return (key & (1L << 47)) != 0; }
+
+    static void applyStateKey(long key) {
+        final int textureId = unpackTextureId(key);
+        final int srcRgb = unpackSrcRgb(key);
+        final int dstRgb = unpackDstRgb(key);
+        final boolean blendEnabled = unpackBlendEnabled(key);
+        final boolean depthMask = unpackDepthMask(key);
+        final boolean tex0Enabled = unpackTex0Enabled(key);
+        final boolean tex1Enabled = unpackTex1Enabled(key);
+
+        GLStateManager.getTextures().getTextureUnitStates(0).setEnabled(tex0Enabled);
+        GLStateManager.getTextures().getTextureUnitStates(1).setEnabled(tex1Enabled);
+        GLStateManager.glBindTexture(GL11.GL_TEXTURE_2D, textureId);
+        GLStateManager.glBlendFunc(srcRgb, dstRgb);
+        if (blendEnabled) {
+            GLStateManager.enableBlend();
+        } else {
+            GLStateManager.disableBlend();
+        }
+        GLStateManager.glDepthMask(depthMask);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/FragmentKey.java

@@ -0,0 +1,368 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import java.util.Arrays;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.states.TexEnvState;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL12;
+import org.lwjgl.opengl.GL13;
+
+/**
+ * Packed-long fragment shader permutation key for FFP emulation.
+ *
+ * Layout:
+ *   long[0]: global bits (10) + unit 0 (47 bits at offset 10)
+ *   long[1..3]: unit 1..3 (47 bits each, low-aligned)
+ * Only max(1, nrEnabledUnits) longs are significant.
+ *
+ * Per-unit packing (47 bits):
+ *   0:     enabled
+ *   1-3:   mode (MODULATE=0..COMBINE=5)
+ *   4:     needsEnvColor
+ *   5-8:   combineRgb (encoded 0-7)
+ *   9-12:  combineAlpha (encoded 0-7)
+ *   13-14: scaleShiftRgb
+ *   15-16: scaleShiftAlpha
+ *   17-21: arg0 RGB (source:3 + operand:2)
+ *   22-26: arg1 RGB
+ *   27-31: arg2 RGB
+ *   32-36: arg0 Alpha
+ *   37-41: arg1 Alpha
+ *   42-46: arg2 Alpha
+ */
+public final class FragmentKey {
+    private static final Logger LOGGER = LogManager.getLogger("FragmentKey");
+
+    public static final int TEX_ENV_MODULATE = 0;
+    public static final int TEX_ENV_REPLACE  = 1;
+    public static final int TEX_ENV_ADD      = 2;
+    public static final int TEX_ENV_DECAL    = 3;
+    public static final int TEX_ENV_BLEND    = 4;
+    public static final int TEX_ENV_COMBINE  = 5;
+
+    public static final int COMBINE_REPLACE      = 0;
+    public static final int COMBINE_MODULATE     = 1;
+    public static final int COMBINE_ADD          = 2;
+    public static final int COMBINE_ADD_SIGNED   = 3;
+    public static final int COMBINE_INTERPOLATE  = 4;
+    public static final int COMBINE_SUBTRACT     = 5;
+    public static final int COMBINE_DOT3_RGB     = 6;
+    public static final int COMBINE_DOT3_RGBA    = 7;
+
+    public static final int SRC_TEXTURE       = 0;
+    public static final int SRC_CONSTANT      = 1;
+    public static final int SRC_PRIMARY_COLOR = 2;
+    public static final int SRC_PREVIOUS      = 3;
+
+    public static final int OP_SRC_COLOR           = 0;
+    public static final int OP_ONE_MINUS_SRC_COLOR = 1;
+    public static final int OP_SRC_ALPHA           = 2;
+    public static final int OP_ONE_MINUS_SRC_ALPHA = 3;
+
+    public static final int FOG_NONE   = 0;
+    public static final int FOG_LINEAR = 1;
+    public static final int FOG_EXP    = 2;
+    public static final int FOG_EXP2   = 3;
+
+    private static final int GLOBAL_BITS = 10;
+    private static final int BIT_FOG_MODE          = 0;  // 2 bits
+    private static final int BIT_ALPHA_TEST        = 2;  // 1 bit
+    private static final int BIT_ALPHA_FUNC        = 3;  // 3 bits
+    private static final int BIT_SEPARATE_SPECULAR = 6;  // 1 bit
+    private static final int BIT_NR_ENABLED_UNITS  = 7;  // 3 bits
+
+    private static final int U_ENABLED         = 0;
+    private static final int U_MODE            = 1;   // 3 bits
+    private static final int U_NEEDS_ENV_COLOR = 4;   // 1 bit
+    private static final int U_COMBINE_RGB     = 5;   // 4 bits
+    private static final int U_COMBINE_ALPHA   = 9;   // 4 bits
+    private static final int U_SCALE_RGB       = 13;  // 2 bits
+    private static final int U_SCALE_ALPHA     = 15;  // 2 bits
+    private static final int U_ARG0_RGB        = 17;  // 5 bits (source:3 + operand:2)
+    private static final int U_ARG1_RGB        = 22;  // 5 bits
+    private static final int U_ARG2_RGB        = 27;  // 5 bits
+    private static final int U_ARG0_ALPHA      = 32;  // 5 bits
+    private static final int U_ARG1_ALPHA      = 37;  // 5 bits
+    private static final int U_ARG2_ALPHA      = 42;  // 5 bits
+
+    static final int MAX_UNITS = 4;
+
+    private final long[] packed;
+    private final int hash;
+
+    private FragmentKey(long[] packed, int hash) {
+        this.packed = packed;
+        this.hash = hash;
+    }
+
+    /**
+     * Pack current GLSM fragment state into pre-allocated output array.
+     * @param out must be at least MAX_UNITS (4) longs
+     * @return number of significant longs (1..4)
+     */
+    public static int packFromState(long[] out) {
+        long global = 0;
+
+        // Fog
+        if (GLStateManager.getFogMode().isEnabled()) {
+            final int fogMode = switch (GLStateManager.getFogState().getFogMode()) {
+                case GL11.GL_LINEAR -> FOG_LINEAR;
+                case GL11.GL_EXP    -> FOG_EXP;
+                case GL11.GL_EXP2   -> FOG_EXP2;
+                default -> FOG_NONE;
+            };
+            global |= (long) fogMode;
+        }
+
+        // Alpha test
+        if (GLStateManager.getAlphaTest().isEnabled()) {
+            global |= (1L << BIT_ALPHA_TEST);
+            global |= ((long) (encodeAlphaFunc(GLStateManager.getAlphaState().getFunction()) & 0x7)) << BIT_ALPHA_FUNC;
+        }
+
+        // Separate specular
+        if (GLStateManager.getLightingState().isEnabled()
+            && GLStateManager.getLightModel().colorControl == GL12.GL_SEPARATE_SPECULAR_COLOR) {
+            global |= (1L << BIT_SEPARATE_SPECULAR);
+        }
+
+        // Per-unit state
+        int highestEnabled = -1;
+        long unit0Bits = 0;
+        for (int i = 0; i < MAX_UNITS; i++) {
+            final boolean texEnabled = GLStateManager.getTextures().getTextureUnitStates(i).isEnabled();
+            if (texEnabled) highestEnabled = i;
+
+            final long unitBits = packUnit(i, texEnabled);
+            if (i == 0) {
+                unit0Bits = unitBits;
+            } else {
+                out[i] = unitBits;
+            }
+        }
+
+        final int nrEnabled = highestEnabled + 1;
+        global |= ((long) (nrEnabled & 0x7)) << BIT_NR_ENABLED_UNITS;
+        global |= (unit0Bits << GLOBAL_BITS);
+        out[0] = global;
+
+        return Math.max(1, nrEnabled);
+    }
+
+    private static long packUnit(int unitIndex, boolean texEnabled) {
+        if (!texEnabled) return 0;
+
+        final TexEnvState envState = GLStateManager.getTextures().getTexEnvState(unitIndex);
+        final int mode = encodeTexEnvMode(envState.mode);
+
+        long bits = 1L; // enabled
+        bits |= ((long) (mode & 0x7)) << U_MODE;
+
+        boolean needsEnvColor = (mode == TEX_ENV_BLEND);
+
+        if (mode == TEX_ENV_COMBINE) {
+            final int combRgb = encodeCombineFunc(envState.combineRgb);
+            final int combAlpha = encodeCombineFunc(envState.combineAlpha);
+            bits |= ((long) (combRgb & 0xF)) << U_COMBINE_RGB;
+            bits |= ((long) (combAlpha & 0xF)) << U_COMBINE_ALPHA;
+            bits |= ((long) (encodeScale(envState.scaleRgb) & 0x3)) << U_SCALE_RGB;
+            bits |= ((long) (encodeScale(envState.scaleAlpha) & 0x3)) << U_SCALE_ALPHA;
+
+            // Only pack args actually used by each channel's combine function.
+            // Unused arg slots stay 0, preventing TexEnvState defaults from inflating the cache.
+            final int numArgsRgb = combineNumArgs(combRgb);
+            final int numArgsAlpha = combineNumArgs(combAlpha);
+            final int maxArgs = Math.max(numArgsRgb, numArgsAlpha);
+
+            for (int a = 0; a < maxArgs; a++) {
+                if (a < numArgsRgb) {
+                    final int srcR = encodeSource(envState.sourceRgb[a]);
+                    final int opR = encodeOperand(envState.operandRgb[a]);
+                    bits |= ((long) ((srcR & 0x7) | ((opR & 0x3) << 3))) << (U_ARG0_RGB + a * 5);
+                    if (srcR == SRC_CONSTANT) needsEnvColor = true;
+                }
+                if (a < numArgsAlpha) {
+                    final int srcA = encodeSource(envState.sourceAlpha[a]);
+                    final int opA = encodeOperand(envState.operandAlpha[a]);
+                    bits |= ((long) ((srcA & 0x7) | ((opA & 0x3) << 3))) << (U_ARG0_ALPHA + a * 5);
+                    if (srcA == SRC_CONSTANT) needsEnvColor = true;
+                }
+            }
+        }
+
+        if (needsEnvColor) {
+            bits |= (1L << U_NEEDS_ENV_COLOR);
+        }
+
+        return bits;
+    }
+
+    /** Create FragmentKey from packed scratch data. Only called on cache miss. */
+    public static FragmentKey fromPacked(long[] scratch, int len) {
+        final long[] copy = Arrays.copyOf(scratch, len);
+        return new FragmentKey(copy, Arrays.hashCode(copy));
+    }
+
+    /** Convenience: pack + create. Allocates. For infrequent paths. */
+    public static FragmentKey fromState() {
+        final long[] scratch = new long[MAX_UNITS];
+        final int len = packFromState(scratch);
+        return fromPacked(scratch, len);
+    }
+
+    @Override
+    public int hashCode() {
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (!(obj instanceof FragmentKey other)) return false;
+        if (hash != other.hash) return false;
+        return Arrays.equals(packed, other.packed);
+    }
+
+    public int fogMode()              { return (int) (packed[0] & 0x3); }
+    public boolean alphaTestEnabled() { return ((packed[0] >> BIT_ALPHA_TEST) & 1) != 0; }
+    public int alphaTestFunc()        { return (int) ((packed[0] >> BIT_ALPHA_FUNC) & 0x7); }
+    public boolean separateSpecular() { return ((packed[0] >> BIT_SEPARATE_SPECULAR) & 1) != 0; }
+    public int nrEnabledUnits()       { return (int) ((packed[0] >> BIT_NR_ENABLED_UNITS) & 0x7); }
+
+    private long unitBits(int i) {
+        return (i == 0) ? (packed[0] >>> GLOBAL_BITS) : packed[i];
+    }
+
+    public boolean unitEnabled(int i)       { return (unitBits(i) & 1) != 0; }
+    public int unitMode(int i)              { return (int) ((unitBits(i) >> U_MODE) & 0x7); }
+    public boolean unitNeedsEnvColor(int i) { return ((unitBits(i) >> U_NEEDS_ENV_COLOR) & 1) != 0; }
+    public int unitCombineRgb(int i)        { return (int) ((unitBits(i) >> U_COMBINE_RGB) & 0xF); }
+    public int unitCombineAlpha(int i)      { return (int) ((unitBits(i) >> U_COMBINE_ALPHA) & 0xF); }
+    public int unitScaleShiftRgb(int i)     { return (int) ((unitBits(i) >> U_SCALE_RGB) & 0x3); }
+    public int unitScaleShiftAlpha(int i)   { return (int) ((unitBits(i) >> U_SCALE_ALPHA) & 0x3); }
+
+    public int unitSourceRgb(int i, int arg)    { return (int) ((unitBits(i) >> (U_ARG0_RGB + arg * 5)) & 0x7); }
+    public int unitOperandRgb(int i, int arg)   { return (int) ((unitBits(i) >> (U_ARG0_RGB + arg * 5 + 3)) & 0x3); }
+    public int unitSourceAlpha(int i, int arg)  { return (int) ((unitBits(i) >> (U_ARG0_ALPHA + arg * 5)) & 0x7); }
+    public int unitOperandAlpha(int i, int arg) { return (int) ((unitBits(i) >> (U_ARG0_ALPHA + arg * 5 + 3)) & 0x3); }
+
+    public boolean textureEnabled() {
+        for (int i = 0; i < nrEnabledUnits(); i++) {
+            if (unitEnabled(i)) return true;
+        }
+        return false;
+    }
+
+    public boolean lightmapEnabled() {
+        return nrEnabledUnits() > 1 && unitEnabled(1);
+    }
+
+    private static int encodeAlphaFunc(int glFunc) {
+        return glFunc & 0x7;
+    }
+
+    static int encodeTexEnvMode(int glMode) {
+        return switch (glMode) {
+            case GL11.GL_MODULATE -> TEX_ENV_MODULATE;
+            case GL11.GL_REPLACE  -> TEX_ENV_REPLACE;
+            case GL11.GL_ADD      -> TEX_ENV_ADD;
+            case GL11.GL_DECAL    -> TEX_ENV_DECAL;
+            case GL11.GL_BLEND    -> TEX_ENV_BLEND;
+            case GL13.GL_COMBINE -> TEX_ENV_COMBINE;
+            default -> TEX_ENV_MODULATE;
+        };
+    }
+
+    static int encodeCombineFunc(int glFunc) {
+        return switch (glFunc) {
+            case GL11.GL_REPLACE     -> COMBINE_REPLACE;
+            case GL11.GL_MODULATE    -> COMBINE_MODULATE;
+            case GL11.GL_ADD         -> COMBINE_ADD;
+            case GL13.GL_ADD_SIGNED  -> COMBINE_ADD_SIGNED;
+            case GL13.GL_INTERPOLATE -> COMBINE_INTERPOLATE;
+            case GL13.GL_SUBTRACT    -> COMBINE_SUBTRACT;
+            case GL13.GL_DOT3_RGB    -> COMBINE_DOT3_RGB;
+            case GL13.GL_DOT3_RGBA   -> COMBINE_DOT3_RGBA;
+            default -> COMBINE_REPLACE;
+        };
+    }
+
+    static int encodeSource(int glSource) {
+        return switch (glSource) {
+            case GL11.GL_TEXTURE       -> SRC_TEXTURE;
+            case GL13.GL_CONSTANT      -> SRC_CONSTANT;
+            case GL13.GL_PRIMARY_COLOR -> SRC_PRIMARY_COLOR;
+            case GL13.GL_PREVIOUS      -> SRC_PREVIOUS;
+            default -> {
+                LOGGER.debug("Unknown TexEnv source 0x{}, falling back to SRC_PREVIOUS", Integer.toHexString(glSource));
+                yield SRC_PREVIOUS;
+            }
+        };
+    }
+
+    static int encodeOperand(int glOperand) {
+        return switch (glOperand) {
+            case GL11.GL_SRC_COLOR           -> OP_SRC_COLOR;
+            case GL11.GL_ONE_MINUS_SRC_COLOR -> OP_ONE_MINUS_SRC_COLOR;
+            case GL11.GL_SRC_ALPHA           -> OP_SRC_ALPHA;
+            case GL11.GL_ONE_MINUS_SRC_ALPHA -> OP_ONE_MINUS_SRC_ALPHA;
+            default -> OP_SRC_COLOR;
+        };
+    }
+
+    /** Number of source/operand args used by the given (encoded) combine function. */
+    public static int combineNumArgs(int func) {
+        return switch (func) {
+            case COMBINE_REPLACE -> 1;
+            case COMBINE_INTERPOLATE -> 3;
+            default -> 2; // MODULATE, ADD, ADD_SIGNED, SUBTRACT, DOT3_*
+        };
+    }
+
+    private static int encodeScale(float scale) {
+        if (scale >= 4.0f) return 2;
+        if (scale >= 2.0f) return 1;
+        return 0;
+    }
+
+    public static int decodeAlphaFunc(int encoded) {
+        return 0x0200 | encoded;
+    }
+
+    @Override
+    public String toString() {
+        final String fogName = switch (fogMode()) {
+            case FOG_NONE   -> "NONE";
+            case FOG_LINEAR -> "LINEAR";
+            case FOG_EXP    -> "EXP";
+            case FOG_EXP2   -> "EXP2";
+            default -> "?";
+        };
+        final StringBuilder sb = new StringBuilder();
+        sb.append(String.format("FFPFragmentKey[fog=%s alpha=%b(%s) specSep=%b units=%d",
+            fogName, alphaTestEnabled(),
+            alphaTestEnabled() ? String.format("0x%04X", decodeAlphaFunc(alphaTestFunc())) : "-",
+            separateSpecular(), nrEnabledUnits()));
+        for (int i = 0; i < nrEnabledUnits(); i++) {
+            if (!unitEnabled(i)) {
+                sb.append(String.format(" u%d=OFF", i));
+            } else {
+                final String modeName = switch (unitMode(i)) {
+                    case TEX_ENV_MODULATE -> "MOD";
+                    case TEX_ENV_REPLACE  -> "REPL";
+                    case TEX_ENV_ADD      -> "ADD";
+                    case TEX_ENV_DECAL    -> "DEC";
+                    case TEX_ENV_BLEND    -> "BL";
+                    case TEX_ENV_COMBINE  -> "COMB";
+                    default -> "?";
+                };
+                sb.append(String.format(" u%d=%s", i, modeName));
+            }
+        }
+        sb.append(']');
+        return sb.toString();
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/FragmentShaderGenerator.java

@@ -0,0 +1,316 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import org.lwjgl.opengl.GL11;
+
+/**
+ * Generates GLSL 330 core fragment shaders for FFP emulation.
+ * Supports per-unit texenv chain including GL_COMBINE mode.
+ * Follows Mesa's ff_fragment_shader.c and st_nir_lower_fog.c.
+ */
+public final class FragmentShaderGenerator {
+
+    private FragmentShaderGenerator() {}
+
+    public static String generate(FragmentKey key) {
+        final StringBuilder sb = new StringBuilder(2048);
+        sb.append("#version 330 core\n\n");
+
+        emitInputs(sb, key);
+        emitUniforms(sb, key);
+        sb.append("out vec4 fragColor;\n\n");
+
+        sb.append("void main() {\n");
+        emitTextureSampling(sb, key);
+        emitTexEnvChain(sb, key);
+        emitSpecularAdd(sb, key);
+        emitAlphaTest(sb, key);
+        emitFog(sb, key);
+        sb.append("  fragColor = color;\n");
+        sb.append("}\n");
+
+        return sb.toString();
+    }
+
+    private static void emitInputs(StringBuilder sb, FragmentKey key) {
+        sb.append("// Inputs from vertex shader\n");
+        sb.append("in vec4 v_Color;\n");
+        if (key.separateSpecular()) {
+            sb.append("in vec3 v_SpecularColor;\n");
+        }
+        if (key.textureEnabled()) {
+            sb.append("in vec4 v_TexCoord0;\n");
+        }
+        if (key.lightmapEnabled()) {
+            sb.append("in vec4 v_TexCoord1;\n");
+        }
+        if (key.fogMode() != FragmentKey.FOG_NONE) {
+            sb.append("in float v_FogCoord;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitUniforms(StringBuilder sb, FragmentKey key) {
+        // Samplers for each enabled unit
+        for (int i = 0; i < key.nrEnabledUnits(); i++) {
+            if (key.unitEnabled(i)) {
+                sb.append("uniform sampler2D u_Sampler").append(i).append(";\n");
+            }
+        }
+        if (key.alphaTestEnabled()) {
+            sb.append("uniform float u_AlphaRef;\n");
+        }
+        // Per-unit texEnvColor uniforms
+        for (int i = 0; i < key.nrEnabledUnits(); i++) {
+            if (key.unitEnabled(i) && key.unitNeedsEnvColor(i)) {
+                sb.append("uniform vec4 u_TexEnvColor").append(i).append(";\n");
+            }
+        }
+        if (key.fogMode() != FragmentKey.FOG_NONE) {
+            sb.append("uniform vec4 u_FogParams;\n");
+            sb.append("uniform vec4 u_FogColor;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitTextureSampling(StringBuilder sb, FragmentKey key) {
+        for (int i = 0; i < key.nrEnabledUnits(); i++) {
+            if (!key.unitEnabled(i)) continue;
+            // Unit 1 is the lightmap — uses v_TexCoord1.
+            // Units 2-3 intentionally share unit 0's texture coordinates since
+            // the vertex shader only provides 2 tex coord varyings (unit 0 and unit 1/lightmap).
+            final String texCoord = (i == 1) ? "v_TexCoord1.st" : "v_TexCoord0.st";
+            sb.append("  vec4 tex").append(i).append("Color = texture(u_Sampler").append(i).append(", ").append(texCoord).append(");\n");
+        }
+    }
+
+    private static void emitTexEnvChain(StringBuilder sb, FragmentKey key) {
+        if (!key.textureEnabled()) {
+            sb.append("  // No texture — vertex color only\n");
+            sb.append("  vec4 color = v_Color;\n");
+            return;
+        }
+
+        // Process units in order; "previous" starts as vertex color
+        boolean firstUnit = true;
+        for (int i = 0; i < key.nrEnabledUnits(); i++) {
+            if (!key.unitEnabled(i)) continue;
+
+            final String texVar = "tex" + i + "Color";
+            final String envColorVar = "u_TexEnvColor" + i;
+            final String prevVar = firstUnit ? "v_Color" : "color";
+            final String assign = firstUnit ? "  vec4 color = " : "  color = ";
+
+            if (key.unitMode(i) == FragmentKey.TEX_ENV_COMBINE) {
+                emitCombineUnit(sb, key, i, texVar, envColorVar, prevVar, assign);
+            } else {
+                emitSimpleUnit(sb, key, i, texVar, envColorVar, prevVar, assign);
+            }
+            firstUnit = false;
+        }
+    }
+
+    private static void emitSimpleUnit(StringBuilder sb, FragmentKey key, int unit, String texVar, String envColorVar, String prevVar, String assign) {
+        switch (key.unitMode(unit)) {
+            case FragmentKey.TEX_ENV_REPLACE -> {
+                sb.append("  // Unit ").append(unit).append(" (REPLACE)\n");
+                sb.append(assign).append(texVar).append(";\n");
+            }
+            case FragmentKey.TEX_ENV_ADD -> {
+                sb.append("  // Unit ").append(unit).append(" (ADD)\n");
+                sb.append(assign).append("vec4(clamp(").append(prevVar).append(".rgb + ").append(texVar).append(".rgb, 0.0, 1.0), ")
+                    .append(prevVar).append(".a * ").append(texVar).append(".a);\n");
+            }
+            case FragmentKey.TEX_ENV_DECAL -> {
+                sb.append("  // Unit ").append(unit).append(" (DECAL)\n");
+                sb.append(assign).append("vec4(mix(").append(prevVar).append(".rgb, ").append(texVar).append(".rgb, ").append(texVar).append(".a), ")
+                    .append(prevVar).append(".a);\n");
+            }
+            case FragmentKey.TEX_ENV_BLEND -> {
+                sb.append("  // Unit ").append(unit).append(" (BLEND)\n");
+                sb.append(assign).append("vec4(").append(prevVar).append(".rgb * (vec3(1.0) - ").append(texVar).append(".rgb) + ")
+                    .append(envColorVar).append(".rgb * ").append(texVar).append(".rgb, ")
+                    .append(prevVar).append(".a * ").append(texVar).append(".a);\n");
+            }
+            default -> { // MODULATE
+                sb.append("  // Unit ").append(unit).append(" (MODULATE)\n");
+                sb.append(assign).append(prevVar).append(" * ").append(texVar).append(";\n");
+            }
+        }
+    }
+
+    /** Emit a GL_COMBINE texenv unit */
+    private static void emitCombineUnit(StringBuilder sb, FragmentKey key, int unit, String texVar, String envColorVar, String prevVar, String assign) {
+        sb.append("  // Unit ").append(unit).append(" (COMBINE)\n");
+
+        final String rgbResult = "combRgb" + unit;
+        final String alphaResult = "combAlpha" + unit;
+
+        if (key.unitCombineRgb(unit) == FragmentKey.COMBINE_DOT3_RGBA) {
+            sb.append("  vec3 ").append(rgbResult).append(";\n");
+            sb.append("  {\n");
+            emitCombineChannel(sb, key, unit, texVar, envColorVar, prevVar, true);
+            sb.append("  }\n");
+            sb.append(assign).append("vec4(").append(rgbResult).append(", ").append(rgbResult).append(".x);\n");
+        } else {
+            sb.append("  vec3 ").append(rgbResult).append(";\n");
+            sb.append("  float ").append(alphaResult).append(";\n");
+            sb.append("  {\n");
+            emitCombineChannel(sb, key, unit, texVar, envColorVar, prevVar, true);
+            emitCombineChannel(sb, key, unit, texVar, envColorVar, prevVar, false);
+            sb.append("  }\n");
+            sb.append(assign).append("vec4(").append(rgbResult).append(", ").append(alphaResult).append(");\n");
+        }
+    }
+
+    /**
+     * Emit one channel (RGB or Alpha) of a GL_COMBINE unit.
+     */
+    private static void emitCombineChannel(StringBuilder sb, FragmentKey key, int unit, String texVar, String envColorVar, String prevVar, boolean isRgb) {
+        final String suffix = isRgb ? "Rgb" : "Alpha";
+        final String type = isRgb ? "vec3" : "float";
+        final int combineFunc = isRgb ? key.unitCombineRgb(unit) : key.unitCombineAlpha(unit);
+        final int scaleShift = isRgb ? key.unitScaleShiftRgb(unit) : key.unitScaleShiftAlpha(unit);
+
+        // Guard: DOT3 is invalid for alpha channel — fallback to REPLACE
+        final int effectiveFunc;
+        if (!isRgb && (combineFunc == FragmentKey.COMBINE_DOT3_RGB || combineFunc == FragmentKey.COMBINE_DOT3_RGBA)) {
+            effectiveFunc = FragmentKey.COMBINE_REPLACE;
+        } else {
+            effectiveFunc = combineFunc;
+        }
+
+        // Determine how many args we need
+        final int numArgs = combineNumArgs(effectiveFunc);
+
+        // Emit argument resolution
+        for (int a = 0; a < numArgs; a++) {
+            final int source = isRgb ? key.unitSourceRgb(unit, a) : key.unitSourceAlpha(unit, a);
+            final int operand = isRgb ? key.unitOperandRgb(unit, a) : key.unitOperandAlpha(unit, a);
+            final String argName = "arg" + suffix + a + "_" + unit;
+            final String sourceExpr = resolveSource(source, texVar, envColorVar, prevVar);
+            final String operandExpr = applyOperand(sourceExpr, operand, isRgb);
+            sb.append("    ").append(type).append(" ").append(argName).append(" = ").append(operandExpr).append(";\n");
+        }
+
+        // Emit combine operation
+        final String resultName = "comb" + suffix + unit;
+        final String a0 = "arg" + suffix + "0_" + unit;
+        final String a1 = "arg" + suffix + "1_" + unit;
+        final String a2 = "arg" + suffix + "2_" + unit;
+
+        sb.append("    ").append(resultName).append(" = ");
+        switch (effectiveFunc) {
+            case FragmentKey.COMBINE_REPLACE -> sb.append(a0);
+            case FragmentKey.COMBINE_MODULATE -> sb.append(a0).append(" * ").append(a1);
+            case FragmentKey.COMBINE_ADD -> sb.append(a0).append(" + ").append(a1);
+            case FragmentKey.COMBINE_ADD_SIGNED ->
+                sb.append(a0).append(" + ").append(a1).append(" - ").append(isRgb ? "vec3(0.5)" : "0.5");
+            case FragmentKey.COMBINE_SUBTRACT -> sb.append(a0).append(" - ").append(a1);
+            case FragmentKey.COMBINE_INTERPOLATE ->
+                sb.append("mix(").append(a1).append(", ").append(a0).append(", ").append(a2).append(")");
+            case FragmentKey.COMBINE_DOT3_RGB, FragmentKey.COMBINE_DOT3_RGBA ->
+                sb.append("vec3(4.0 * dot(").append(a0).append(" - vec3(0.5), ").append(a1).append(" - vec3(0.5)))");
+            default -> sb.append(a0); // fallback to REPLACE
+        }
+        sb.append(";\n");
+
+        // Apply scale
+        if (scaleShift > 0) {
+            final String scaleFactor = scaleShift == 1 ? "2.0" : "4.0";
+            sb.append("    ").append(resultName).append(" *= ").append(scaleFactor).append(";\n");
+        }
+
+        // Clamp
+        sb.append("    ").append(resultName).append(" = clamp(").append(resultName).append(", ")
+            .append(isRgb ? "vec3(0.0), vec3(1.0)" : "0.0, 1.0").append(");\n");
+    }
+
+    private static String resolveSource(int source, String texVar, String envColorVar, String prevVar) {
+        return switch (source) {
+            case FragmentKey.SRC_TEXTURE -> texVar;
+            case FragmentKey.SRC_CONSTANT -> envColorVar;
+            case FragmentKey.SRC_PRIMARY_COLOR -> "v_Color";
+            case FragmentKey.SRC_PREVIOUS -> prevVar;
+            default -> prevVar;
+        };
+    }
+
+    private static String applyOperand(String sourceExpr, int operand, boolean isRgb) {
+        if (isRgb) {
+            return switch (operand) {
+                case FragmentKey.OP_SRC_COLOR -> sourceExpr + ".rgb";
+                case FragmentKey.OP_ONE_MINUS_SRC_COLOR -> "(vec3(1.0) - " + sourceExpr + ".rgb)";
+                case FragmentKey.OP_SRC_ALPHA -> "vec3(" + sourceExpr + ".a)";
+                case FragmentKey.OP_ONE_MINUS_SRC_ALPHA -> "vec3(1.0 - " + sourceExpr + ".a)";
+                default -> sourceExpr + ".rgb";
+            };
+        } else {
+            return switch (operand) {
+                case FragmentKey.OP_SRC_ALPHA -> sourceExpr + ".a";
+                case FragmentKey.OP_ONE_MINUS_SRC_ALPHA -> "(1.0 - " + sourceExpr + ".a)";
+                // Per GL spec, alpha channel operands are SRC_ALPHA or ONE_MINUS_SRC_ALPHA only, but handle color operands gracefully
+                case FragmentKey.OP_SRC_COLOR -> sourceExpr + ".a";
+                case FragmentKey.OP_ONE_MINUS_SRC_COLOR -> "(1.0 - " + sourceExpr + ".a)";
+                default -> sourceExpr + ".a";
+            };
+        }
+    }
+
+    private static int combineNumArgs(int func) {
+        return FragmentKey.combineNumArgs(func);
+    }
+
+    private static void emitSpecularAdd(StringBuilder sb, FragmentKey key) {
+        if (key.separateSpecular()) {
+            sb.append("  // Add separate specular\n");
+            sb.append("  color.rgb += v_SpecularColor;\n");
+        }
+    }
+
+    private static void emitAlphaTest(StringBuilder sb, FragmentKey key) {
+        if (!key.alphaTestEnabled()) return;
+
+        sb.append("  // Alpha test\n");
+        final int func = FragmentKey.decodeAlphaFunc(key.alphaTestFunc());
+
+        switch (func) {
+            case GL11.GL_NEVER ->
+                sb.append("  discard;\n");
+            case GL11.GL_LESS ->
+                sb.append("  if (color.a >= u_AlphaRef) discard;\n");
+            case GL11.GL_EQUAL ->
+                sb.append("  if (color.a != u_AlphaRef) discard;\n");
+            case GL11.GL_LEQUAL ->
+                sb.append("  if (color.a > u_AlphaRef) discard;\n");
+            case GL11.GL_GREATER ->
+                sb.append("  if (color.a <= u_AlphaRef) discard;\n");
+            case GL11.GL_NOTEQUAL ->
+                sb.append("  if (color.a == u_AlphaRef) discard;\n");
+            case GL11.GL_GEQUAL ->
+                sb.append("  if (color.a < u_AlphaRef) discard;\n");
+            case GL11.GL_ALWAYS -> {}
+        }
+    }
+
+    private static void emitFog(StringBuilder sb, FragmentKey key) {
+        final int fogMode = key.fogMode();
+        if (fogMode == FragmentKey.FOG_NONE) return;
+
+        sb.append("  // Fog\n");
+        sb.append("  float f;\n");
+
+        switch (fogMode) {
+            case FragmentKey.FOG_LINEAR ->
+                sb.append("  f = v_FogCoord * u_FogParams.x + u_FogParams.y;\n");
+            case FragmentKey.FOG_EXP ->
+                sb.append("  f = exp2(-(v_FogCoord * u_FogParams.z));\n");
+            case FragmentKey.FOG_EXP2 -> {
+                sb.append("  float fogTmp = v_FogCoord * u_FogParams.w;\n");
+                sb.append("  f = exp2(-(fogTmp * fogTmp));\n");
+            }
+        }
+
+        sb.append("  f = clamp(f, 0.0, 1.0);\n");
+        sb.append("  color.rgb = mix(u_FogColor.rgb, color.rgb, f);\n");
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/GeometryShaderGenerator.java

@@ -0,0 +1,104 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+/**
+ * Generates GLSL 330 core geometry shaders for wide line emulation.
+ */
+public final class GeometryShaderGenerator {
+
+    private GeometryShaderGenerator() {}
+
+    public static String generate(VertexKey key) {
+        final StringBuilder sb = new StringBuilder(1024);
+        sb.append("#version 330 core\n\n");
+
+        sb.append("layout(lines) in;\n");
+        sb.append("layout(triangle_strip, max_vertices = 4) out;\n\n");
+
+        sb.append("uniform vec2 u_ViewportSize;\n");
+        sb.append("uniform float u_LineWidth;\n\n");
+
+        sb.append("// Pass-through varyings\n");
+        sb.append("in vec4 v_Color_gs[];\n");
+        if (key.separateSpecular()) {
+            sb.append("in vec3 v_SpecularColor_gs[];\n");
+        }
+        if (key.textureEnabled() || key.hasVertexTexCoord() || key.texGenEnabled()) {
+            sb.append("in vec4 v_TexCoord0_gs[];\n");
+        }
+        if (key.lightmapEnabled()) {
+            sb.append("in vec4 v_TexCoord1_gs[];\n");
+        }
+        if (key.fogEnabled()) {
+            sb.append("in float v_FogCoord_gs[];\n");
+        }
+        sb.append('\n');
+
+        sb.append("out vec4 v_Color;\n");
+        if (key.separateSpecular()) {
+            sb.append("out vec3 v_SpecularColor;\n");
+        }
+        if (key.textureEnabled() || key.hasVertexTexCoord() || key.texGenEnabled()) {
+            sb.append("out vec4 v_TexCoord0;\n");
+        }
+        if (key.lightmapEnabled()) {
+            sb.append("out vec4 v_TexCoord1;\n");
+        }
+        if (key.fogEnabled()) {
+            sb.append("out float v_FogCoord;\n");
+        }
+        sb.append('\n');
+
+        sb.append("void main() {\n");
+        sb.append("    vec4 c0 = gl_in[0].gl_Position;\n");
+        sb.append("    vec4 c1 = gl_in[1].gl_Position;\n\n");
+
+        sb.append("    // NDC positions\n");
+        sb.append("    vec2 n0 = c0.xy / c0.w;\n");
+        sb.append("    vec2 n1 = c1.xy / c1.w;\n\n");
+
+        sb.append("    // Screen-space direction and perpendicular\n");
+        sb.append("    vec2 dir = normalize((n1 - n0) * u_ViewportSize);\n");
+        sb.append("    vec2 offset = vec2(-dir.y, dir.x) * u_LineWidth / u_ViewportSize;\n\n");
+
+        emitVertex(sb, key, 0, "+offset");
+        emitVertex(sb, key, 0, "-offset");
+        emitVertex(sb, key, 1, "+offset");
+        emitVertex(sb, key, 1, "-offset");
+
+        sb.append("    EndPrimitive();\n");
+        sb.append("}\n");
+
+        return sb.toString();
+    }
+
+    private static void emitVertex(StringBuilder sb, VertexKey key, int endpointIdx, String offsetExpr) {
+        final String ci = "c" + endpointIdx;
+        final String ni = "n" + endpointIdx;
+        final String idx = "[" + endpointIdx + "]";
+
+        sb.append("    // Endpoint ").append(endpointIdx).append(' ').append(offsetExpr).append('\n');
+
+        sb.append("    v_Color = v_Color_gs").append(idx).append(";\n");
+        if (key.separateSpecular()) {
+            sb.append("    v_SpecularColor = v_SpecularColor_gs").append(idx).append(";\n");
+        }
+        if (key.textureEnabled() || key.hasVertexTexCoord() || key.texGenEnabled()) {
+            sb.append("    v_TexCoord0 = v_TexCoord0_gs").append(idx).append(";\n");
+        }
+        if (key.lightmapEnabled()) {
+            sb.append("    v_TexCoord1 = v_TexCoord1_gs").append(idx).append(";\n");
+        }
+        if (key.fogEnabled()) {
+            sb.append("    v_FogCoord = v_FogCoord_gs").append(idx).append(";\n");
+        }
+
+        if (key.clipPlanesEnabled()) {
+            for (int i = 0; i < 8; i++) {
+                sb.append("    gl_ClipDistance[").append(i).append("] = gl_in").append(idx).append(".gl_ClipDistance[").append(i).append("];\n");
+            }
+        }
+
+        sb.append("    gl_Position = vec4((").append(ni).append(' ').append(offsetExpr).append(") * ").append(ci).append(".w, ").append(ci).append(".z, ").append(ci).append(".w);\n");
+        sb.append("    EmitVertex();\n\n");
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/Program.java

@@ -0,0 +1,273 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizons.angelica.glsm.GLDebug;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.RenderSystem;
+import lombok.Getter;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL20;
+import org.lwjgl.opengl.GL32;
+import org.lwjgl.opengl.GL40;
+import org.lwjgl.opengl.GL43;
+import org.lwjgl.opengl.KHRDebug;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * A compiled and linked FFP emulation program (vertex + fragment + optional geometry shaders). Owns the GL program handle and caches uniform locations.
+ */
+public class Program {
+
+    private static final Logger LOGGER = LogManager.getLogger("FFPProgram");
+    private static final AtomicInteger PROGRAM_COUNTER = new AtomicInteger();
+
+    @Getter private final int programId;
+    @Getter private final VertexKey vertexKey;
+    @Getter private final FragmentKey fragmentKey;
+
+    // Uniform locations (-1 = not present in this variant)
+    // Matrices
+    public int locModelViewMatrix = -1;
+    public int locProjectionMatrix = -1;
+    public int locMVPMatrix = -1;
+    public int locNormalMatrix = -1;
+    public int locTextureMatrix0 = -1;
+
+    // Current state defaults
+    public int locCurrentNormal = -1;
+    public int locCurrentColor = -1;
+    public int locCurrentTexCoord = -1;
+    public int locCurrentLightmapCoord = -1;
+    public int locLightmapTextureMatrix = -1;
+
+    // Lighting - color material path (raw values)
+    public int locLightModelAmbient = -1;
+    public int locMaterialEmission = -1;
+    public int locMaterialAmbient = -1;
+    public int locMaterialDiffuse = -1;
+    public int locMaterialSpecular = -1;
+    public int locMaterialShininess = -1;
+    public int locLight0Ambient = -1;
+    public int locLight0Diffuse = -1;
+    public int locLight0Specular = -1;
+    public int locLight1Ambient = -1;
+    public int locLight1Diffuse = -1;
+    public int locLight1Specular = -1;
+
+    // Lighting - pre-computed path
+    public int locSceneColor = -1;
+    public int locLightProd0Ambient = -1;
+    public int locLightProd0Diffuse = -1;
+    public int locLightProd0Specular = -1;
+    public int locLightProd1Ambient = -1;
+    public int locLightProd1Diffuse = -1;
+    public int locLightProd1Specular = -1;
+
+    // Light positions
+    public int locLight0Position = -1;
+    public int locLight1Position = -1;
+
+    // Normal scale (for rescale normals)
+    public int locNormalScale = -1;
+
+    // TexGen plane uniforms
+    public int locTexGenObjPlaneS = -1;
+    public int locTexGenObjPlaneT = -1;
+    public int locTexGenObjPlaneR = -1;
+    public int locTexGenObjPlaneQ = -1;
+    public int locTexGenEyePlaneS = -1;
+    public int locTexGenEyePlaneT = -1;
+    public int locTexGenEyePlaneR = -1;
+    public int locTexGenEyePlaneQ = -1;
+
+    // Clip planes
+    public int locClipPlanes = -1;
+
+    // Wide line emulation (geometry shader)
+    public int locViewportSize = -1;
+    public int locLineWidth = -1;
+
+    // Fragment uniforms
+    public final int[] locSampler = { -1, -1, -1, -1 };
+    public int locAlphaRef = -1;
+    public final int[] locTexEnvColor = { -1, -1, -1, -1 };
+    public int locFogParams = -1;
+    public int locFogColor = -1;
+
+    Program(int programId, VertexKey vertexKey, FragmentKey fragmentKey) {
+        this.programId = programId;
+        this.vertexKey = vertexKey;
+        this.fragmentKey = fragmentKey;
+        resolveLocations();
+    }
+
+    private void resolveLocations() {
+        locModelViewMatrix = loc("u_ModelViewMatrix");
+        locProjectionMatrix = loc("u_ProjectionMatrix");
+        locMVPMatrix = loc("u_MVPMatrix");
+        locNormalMatrix = loc("u_NormalMatrix");
+        locTextureMatrix0 = loc("u_TextureMatrix0");
+
+        locCurrentNormal = loc("u_CurrentNormal");
+        locCurrentColor = loc("u_CurrentColor");
+        locCurrentTexCoord = loc("u_CurrentTexCoord");
+        locCurrentLightmapCoord = loc("u_CurrentLightmapCoord");
+        locLightmapTextureMatrix = loc("u_LightmapTextureMatrix");
+
+        // Color material path
+        locLightModelAmbient = loc("u_LightModelAmbient");
+        locMaterialEmission = loc("u_MaterialEmission");
+        locMaterialAmbient = loc("u_MaterialAmbient");
+        locMaterialDiffuse = loc("u_MaterialDiffuse");
+        locMaterialSpecular = loc("u_MaterialSpecular");
+        locMaterialShininess = loc("u_MaterialShininess");
+        locLight0Ambient = loc("u_Light0Ambient");
+        locLight0Diffuse = loc("u_Light0Diffuse");
+        locLight0Specular = loc("u_Light0Specular");
+        locLight1Ambient = loc("u_Light1Ambient");
+        locLight1Diffuse = loc("u_Light1Diffuse");
+        locLight1Specular = loc("u_Light1Specular");
+
+        // Pre-computed path
+        locSceneColor = loc("u_SceneColor");
+        locLightProd0Ambient = loc("u_LightProd0Ambient");
+        locLightProd0Diffuse = loc("u_LightProd0Diffuse");
+        locLightProd0Specular = loc("u_LightProd0Specular");
+        locLightProd1Ambient = loc("u_LightProd1Ambient");
+        locLightProd1Diffuse = loc("u_LightProd1Diffuse");
+        locLightProd1Specular = loc("u_LightProd1Specular");
+
+        // Light positions
+        locLight0Position = loc("u_Light0Position");
+        locLight1Position = loc("u_Light1Position");
+
+        locNormalScale = loc("u_NormalScale");
+
+        // TexGen
+        locTexGenObjPlaneS = loc("u_TexGenObjPlaneS");
+        locTexGenObjPlaneT = loc("u_TexGenObjPlaneT");
+        locTexGenObjPlaneR = loc("u_TexGenObjPlaneR");
+        locTexGenObjPlaneQ = loc("u_TexGenObjPlaneQ");
+        locTexGenEyePlaneS = loc("u_TexGenEyePlaneS");
+        locTexGenEyePlaneT = loc("u_TexGenEyePlaneT");
+        locTexGenEyePlaneR = loc("u_TexGenEyePlaneR");
+        locTexGenEyePlaneQ = loc("u_TexGenEyePlaneQ");
+
+        // Clip planes
+        locClipPlanes = loc("u_ClipPlane[0]");
+
+        // Wide line emulation
+        locViewportSize = loc("u_ViewportSize");
+        locLineWidth = loc("u_LineWidth");
+
+        // Fragment
+        for (int i = 0; i < 4; i++) {
+            locSampler[i] = loc("u_Sampler" + i);
+        }
+        locAlphaRef = loc("u_AlphaRef");
+        for (int i = 0; i < 4; i++) {
+            locTexEnvColor[i] = loc("u_TexEnvColor" + i);
+        }
+        locFogParams = loc("u_FogParams");
+        locFogColor = loc("u_FogColor");
+    }
+
+    private int loc(String name) {
+        return GL20.glGetUniformLocation(programId, name);
+    }
+
+    public void destroy() {
+        GL20.glDeleteProgram(programId);
+    }
+
+    /**
+     * Compile vertex + fragment + optional geometry shaders, link into a program, and return the FFPProgram.
+     */
+    static Program create(VertexKey vk, FragmentKey fk, String vertSrc, String fragSrc, String geomSrc) {
+        final int id = PROGRAM_COUNTER.getAndIncrement();
+        final String vkHex = Long.toHexString(vk.pack());
+        final boolean hasGeom = geomSrc != null;
+
+        int shaderCount = 0;
+        final int[] shaders = new int[5]; // vertex, fragment, geometry, tess control, tess evaluation
+        int program = 0;
+        try {
+            shaders[shaderCount++] = compileShader(GL20.GL_VERTEX_SHADER, vertSrc, "ffp_v_" + vkHex);
+            shaders[shaderCount++] = compileShader(GL20.GL_FRAGMENT_SHADER, fragSrc, "ffp_f_" + id);
+            if (geomSrc != null) {
+                shaders[shaderCount++] = compileShader(GL32.GL_GEOMETRY_SHADER, geomSrc, "ffp_g_" + id);
+            }
+
+            program = GL20.glCreateProgram();
+            for (int i = 0; i < shaderCount; i++) GL20.glAttachShader(program, shaders[i]);
+            GL20.glLinkProgram(program);
+
+            final String log = RenderSystem.getProgramInfoLog(program);
+            if (!log.isEmpty()) {
+                LOGGER.warn("FFP program link log (vk=0x{}, fk={}): {}", vkHex, fk, log);
+            }
+
+            if (GL20.glGetProgrami(program, GL20.GL_LINK_STATUS) != GL11.GL_TRUE) {
+                throw new RuntimeException("FFP shader link failed (vk=0x" + vkHex + ", fk=" + fk + "): " + log);
+            }
+
+            final String debugName = "FFP(v=0x" + vkHex + ",f=" + id + (hasGeom ? ",g" : "") + ")";
+            GLDebug.nameObject(KHRDebug.GL_PROGRAM, program, debugName);
+
+            // Detach and delete individual shaders — they're linked into the program
+            for (int i = 0; i < shaderCount; i++) {
+                GL20.glDetachShader(program, shaders[i]);
+                GL20.glDeleteShader(shaders[i]);
+            }
+            shaderCount = 0;
+
+            final Program ffpProgram = new Program(program, vk, fk);
+
+            final int previousProgram = GLStateManager.getActiveProgram();
+            GL20.glUseProgram(program);
+            for (int i = 0; i < 4; i++) {
+                if (ffpProgram.locSampler[i] != -1) GL20.glUniform1i(ffpProgram.locSampler[i], i);
+            }
+            GL20.glUseProgram(previousProgram);
+
+            return ffpProgram;
+        } catch (RuntimeException e) {
+            if (program != 0) GL20.glDeleteProgram(program);
+            for (int i = 0; i < shaderCount; i++) GL20.glDeleteShader(shaders[i]);
+            throw e;
+        }
+    }
+
+    private static int compileShader(int type, String src, String name) {
+        final int shader = GL20.glCreateShader(type);
+        GL20.glShaderSource(shader, src);
+        GL20.glCompileShader(shader);
+
+        final String typeName = switch (type) {
+            case GL20.GL_VERTEX_SHADER -> "vertex";
+            case GL20.GL_FRAGMENT_SHADER -> "fragment";
+            case GL32.GL_GEOMETRY_SHADER -> "geometry";
+            case GL40.GL_TESS_CONTROL_SHADER -> "tess_control";
+            case GL40.GL_TESS_EVALUATION_SHADER -> "tess_evaluation";
+            case GL43.GL_COMPUTE_SHADER -> "compute";
+            default -> "unknown(0x" + Integer.toHexString(type) + ")";
+        };
+        GLDebug.nameObject(KHRDebug.GL_SHADER, shader, name + "(" + typeName + ")");
+
+        final String log = RenderSystem.getShaderInfoLog(shader);
+        if (!log.isEmpty()) {
+            LOGGER.warn("FFP {} shader compilation log for {}: {}", typeName, name, log);
+        }
+
+        final int result = GL20.glGetShaderi(shader, GL20.GL_COMPILE_STATUS);
+        if (result != GL11.GL_TRUE) {
+            LOGGER.error("FFP {} shader source:\n{}", typeName, src);
+            GL20.glDeleteShader(shader);
+            throw new RuntimeException("FFP " + typeName + " shader compilation failed for " + name + ": " + log);
+        }
+
+        return shader;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/ShaderCache.java

@@ -0,0 +1,296 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+import lombok.Setter;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.IdentityHashMap;
+
+
+/**
+ * Open-addressed cache for FFP shader program variants.
+ * Keyed on (vertexKey, fragmentKey) pairs stored inline as raw longs — zero allocation on cache hits.
+ * Converges on Mesa's prog_cache.c: hash+memcmp over packed bytes, open addressing.
+ *
+ * <p>Layout per slot in {@code keys[]}: {@link #SLOT_STRIDE}=6 longs
+ * <pre>
+ *   [0]: vertexKeyPacked
+ *   [1]: (fkLen &lt;&lt; 48) | (hash &amp; 0x0000_FFFF_FFFF_FFFF)  — never 0 for valid entries (fkLen &gt;= 1)
+ *   [2..5]: fk0..fk3
+ * </pre>
+ */
+public class ShaderCache {
+    private static final Logger LOGGER = LogManager.getLogger("FFPShaderCache");
+    private static final int SLOT_STRIDE = 6;
+    private static final int INITIAL_CAPACITY = 64; // power of 2
+    private static final long EMPTY_MARKER = 0L; // slot [1] == 0 means empty (fkLen >= 1 guarantees nonzero)
+
+    private final Long2ObjectOpenHashMap<String> vertexSourceCache = new Long2ObjectOpenHashMap<>();
+    private final Long2ObjectOpenHashMap<String> geometrySourceCache = new Long2ObjectOpenHashMap<>();
+
+    // Open-addressed table — parallel arrays
+    private long[] keys;
+    private Program[] programs;
+    private String[] fragSources; // fragment source per slot; reused across VK variants via findFragSource
+    private int capacity;
+    private int count;
+    private int uniqueFragCount;
+
+    // Fast-path: last-used key (raw longs, no objects)
+    private long lastVK = Long.MIN_VALUE;
+    private int lastFKLen;
+    private long lastFK0, lastFK1, lastFK2, lastFK3;
+    private Program lastProgram;
+
+    private int fragmentDumpCounter;
+
+    @Setter private Path dumpDir = null;
+
+    public ShaderCache() {
+        capacity = INITIAL_CAPACITY;
+        keys = new long[capacity * SLOT_STRIDE];
+        programs = new Program[capacity];
+        fragSources = new String[capacity];
+    }
+
+    /**
+     * Get or create an FFP program for the given state keys.
+     *
+     * @param vkPacked packed vertex key
+     * @param fkPacked pre-allocated scratch array with packed fragment key longs
+     * @param fkLen number of significant longs in fkPacked (1..4)
+     */
+    public Program getOrCreate(long vkPacked, long[] fkPacked, int fkLen) {
+        // Fast-path: compare raw longs inline
+        if (vkPacked == lastVK && fkLen == lastFKLen && lastProgram != null
+            && fkPacked[0] == lastFK0
+            && (fkLen < 2 || fkPacked[1] == lastFK1)
+            && (fkLen < 3 || fkPacked[2] == lastFK2)
+            && (fkLen < 4 || fkPacked[3] == lastFK3)) {
+            return lastProgram;
+        }
+
+        final long hash = hashKey(vkPacked, fkPacked, fkLen);
+        final long storedWord = ((long) fkLen << 48) | (hash & 0x0000_FFFF_FFFF_FFFFL);
+        final int mask = capacity - 1;
+        int idx = (int) (hash & mask);
+        while (true) {
+            final int base = idx * SLOT_STRIDE;
+            final long slot1 = keys[base + 1];
+            if (slot1 == EMPTY_MARKER) {
+                break;
+            }
+            if (slot1 == storedWord && keys[base] == vkPacked && keysMatch(base + 2, fkPacked, fkLen)) {
+                final Program p = programs[idx];
+                setLastUsed(vkPacked, fkPacked, fkLen, p);
+                return p;
+            }
+            idx = (idx + 1) & mask;
+        }
+
+        if (count >= (capacity * 3) / 4) {
+            grow();
+            return getOrCreate(vkPacked, fkPacked, fkLen);
+        }
+
+        final VertexKey vk = VertexKey.fromPacked(vkPacked);
+        final String vertSrc = getOrGenerateVertex(vk);
+
+        final FragmentKey fk = FragmentKey.fromPacked(fkPacked, fkLen);
+        String fragSrc = findFragSource(fkPacked, fkLen);
+        if (fragSrc == null) {
+            fragSrc = FragmentShaderGenerator.generate(fk);
+            uniqueFragCount++;
+        }
+
+        final String geomSrc = vk.wideLineEmulation() ? getOrGenerateGeometry(vk) : null;
+        final Program program = Program.create(vk, fk, vertSrc, fragSrc, geomSrc);
+
+        final int insertIdx = findEmptySlot(hash);
+        final int base = insertIdx * SLOT_STRIDE;
+        keys[base] = vkPacked;
+        keys[base + 1] = storedWord;
+        for (int i = 0; i < fkLen; i++) keys[base + 2 + i] = fkPacked[i];
+        programs[insertIdx] = program;
+        fragSources[insertIdx] = fragSrc;
+        count++;
+
+        setLastUsed(vkPacked, fkPacked, fkLen, program);
+
+        LOGGER.debug("FFP variant compiled: {} + {} (total: {} programs)", vk, fk, count);
+
+        if (dumpDir != null) {
+            dumpShader(Long.toHexString(vkPacked), ".vert.glsl", vertSrc);
+            dumpShader("frag_" + fragmentDumpCounter++, ".frag.glsl", fragSrc);
+            if (geomSrc != null) {
+                dumpShader(Long.toHexString(vkPacked), ".geom.glsl", geomSrc);
+            }
+        }
+
+        return program;
+    }
+
+    private String findFragSource(long[] fkPacked, int fkLen) {
+        for (int i = 0; i < capacity; i++) {
+            final int base = i * SLOT_STRIDE;
+            if (keys[base + 1] == EMPTY_MARKER) continue;
+            final int storedLen = (int) (keys[base + 1] >>> 48);
+            if (storedLen != fkLen) continue;
+            if (keysMatch(base + 2, fkPacked, fkLen)) {
+                return fragSources[i];
+            }
+        }
+        return null;
+    }
+
+    private boolean keysMatch(int keysOffset, long[] fkPacked, int fkLen) {
+        for (int i = 0; i < fkLen; i++) {
+            if (keys[keysOffset + i] != fkPacked[i]) return false;
+        }
+        return true;
+    }
+
+    private void setLastUsed(long vkPacked, long[] fkPacked, int fkLen, Program program) {
+        lastVK = vkPacked;
+        lastFKLen = fkLen;
+        lastFK0 = fkPacked[0];
+        lastFK1 = fkLen >= 2 ? fkPacked[1] : 0;
+        lastFK2 = fkLen >= 3 ? fkPacked[2] : 0;
+        lastFK3 = fkLen >= 4 ? fkPacked[3] : 0;
+        lastProgram = program;
+    }
+
+    private int findEmptySlot(long hash) {
+        final int mask = capacity - 1;
+        int idx = (int) (hash & mask);
+        while (keys[idx * SLOT_STRIDE + 1] != EMPTY_MARKER) {
+            idx = (idx + 1) & mask;
+        }
+        return idx;
+    }
+
+    /**
+     * Hash over (vk + fk longs). Adapted from Mesa's hash_key — mix-rotate-multiply.
+     */
+    private static long hashKey(long vkPacked, long[] fkPacked, int fkLen) {
+        long h = vkPacked * 0x9E3779B97F4A7C15L;
+        for (int i = 0; i < fkLen; i++) {
+            h ^= fkPacked[i] * 0x517CC1B727220A95L;
+            h = Long.rotateLeft(h, 31) * 0x9E3779B97F4A7C15L;
+        }
+        return h | 1L; // ensure nonzero lower bits
+    }
+
+    private void grow() {
+        final int oldCap = capacity;
+        final long[] oldKeys = keys;
+        final Program[] oldPrograms = programs;
+        final String[] oldFragSources = fragSources;
+
+        capacity = oldCap * 2;
+        keys = new long[capacity * SLOT_STRIDE];
+        programs = new Program[capacity];
+        fragSources = new String[capacity];
+        count = 0;
+
+        final int mask = capacity - 1;
+        for (int i = 0; i < oldCap; i++) {
+            final int oldBase = i * SLOT_STRIDE;
+            if (oldKeys[oldBase + 1] == EMPTY_MARKER) continue;
+
+            final long storedHash = oldKeys[oldBase + 1] & 0x0000_FFFF_FFFF_FFFFL;
+            int idx = (int) (storedHash & mask);
+            while (keys[idx * SLOT_STRIDE + 1] != EMPTY_MARKER) {
+                idx = (idx + 1) & mask;
+            }
+            final int newBase = idx * SLOT_STRIDE;
+            System.arraycopy(oldKeys, oldBase, keys, newBase, SLOT_STRIDE);
+            programs[idx] = oldPrograms[i];
+            fragSources[idx] = oldFragSources[i];
+            count++;
+        }
+    }
+
+    private String getOrGenerateVertex(VertexKey vk) {
+        return vertexSourceCache.computeIfAbsent(vk.pack(), k -> VertexShaderGenerator.generate(vk));
+    }
+
+    private String getOrGenerateGeometry(VertexKey vk) {
+        return geometrySourceCache.computeIfAbsent(vk.pack(), k -> GeometryShaderGenerator.generate(vk));
+    }
+
+    private void dumpShader(String name, String suffix, String source) {
+        if (dumpDir == null) return;
+        try {
+            Files.createDirectories(dumpDir);
+            final Path file = dumpDir.resolve("ffp_" + name + suffix);
+            if (!Files.exists(file)) {
+                Files.writeString(file, source, StandardCharsets.UTF_8);
+            }
+        } catch (IOException e) {
+            LOGGER.warn("Failed to dump FFP shader to {}: {}", dumpDir, e.getMessage());
+        }
+    }
+
+    /** Dump all cached shaders to disk. */
+    public void dumpAll(Path outputDir) {
+        try {
+            Files.createDirectories(outputDir);
+            for (var entry : vertexSourceCache.entrySet()) {
+                dumpShader(Long.toHexString(entry.getKey()), ".vert.glsl", entry.getValue());
+            }
+            final IdentityHashMap<String, Integer> seen = new IdentityHashMap<>();
+            for (int i = 0; i < capacity; i++) {
+                if (fragSources[i] != null && !seen.containsKey(fragSources[i])) {
+                    final int idx = seen.size();
+                    seen.put(fragSources[i], idx);
+                    dumpShader("frag_" + idx, ".frag.glsl", fragSources[i]);
+                }
+            }
+            for (var entry : geometrySourceCache.entrySet()) {
+                dumpShader(Long.toHexString(entry.getKey()), ".geom.glsl", entry.getValue());
+            }
+            LOGGER.info("Dumped {} vertex, {} geometry, and {} fragment FFP shader sources to {}",
+                vertexSourceCache.size(), geometrySourceCache.size(), seen.size(), outputDir);
+        } catch (IOException e) {
+            LOGGER.warn("Failed to dump FFP shaders: {}", e.getMessage());
+        }
+    }
+
+    /** Destroy all cached programs and clear caches. */
+    public void destroy() {
+        for (int i = 0; i < capacity; i++) {
+            if (programs[i] != null) {
+                programs[i].destroy();
+            }
+        }
+        Arrays.fill(keys, 0);
+        Arrays.fill(programs, null);
+        Arrays.fill(fragSources, null);
+        count = 0;
+        uniqueFragCount = 0;
+        vertexSourceCache.clear();
+        geometrySourceCache.clear();
+        lastProgram = null;
+        lastVK = Long.MIN_VALUE;
+        LOGGER.debug("FFP shader cache cleared");
+    }
+
+    public int getProgramCount() {
+        return count;
+    }
+
+    public int getVertexVariantCount() {
+        return vertexSourceCache.size();
+    }
+
+    public int getFragmentVariantCount() {
+        return uniqueFragCount;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/ShaderManager.java

@@ -0,0 +1,203 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import java.util.Arrays;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.stacks.IStateStack;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFlags;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
+import com.gtnewhorizons.angelica.glsm.CompatUniformManager;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.stacks.Vec3fStack;
+import com.gtnewhorizons.angelica.glsm.stacks.Vec4fStack;
+import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
+import lombok.Getter;
+import net.coderbot.iris.gl.blending.BlendModeStorage;
+import net.minecraft.launchwrapper.Launch;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.joml.Vector3f;
+import org.joml.Vector4f;
+import org.lwjgl.opengl.GL20;
+
+import java.nio.file.Paths;
+
+/**
+ * FFP shader manager
+ */
+public class ShaderManager {
+    private static final Logger LOGGER = LogManager.getLogger("FFPShaderManager");
+
+    private static final class Holder { static final ShaderManager INSTANCE = new ShaderManager(); }
+
+    private final ShaderCache cache = new ShaderCache();
+    private final Uniforms uniforms = new Uniforms();
+    private final Int2IntOpenHashMap vaoVertexFlags = new Int2IntOpenHashMap();
+
+    @Getter
+    private boolean active = false;
+    private Program currentProgram = null;
+    private long currentVertexKeyPacked = Long.MIN_VALUE;
+    private final long[] currentFKScratch = new long[FragmentKey.MAX_UNITS];
+    private final long[] currentFKPacked = new long[FragmentKey.MAX_UNITS];
+    private int currentFKLen = 0;
+
+    @Getter private static final Vector3f currentNormal = new Vector3f(0.0f, 0.0f, 1.0f);
+    @Getter private static final Vector4f currentTexCoord = new Vector4f(0.0f, 0.0f, 0.0f, 1.0f);
+    @Getter private static final Vec3fStack normalStack = new Vec3fStack(currentNormal);
+    @Getter private static final Vec4fStack texCoordStack = new Vec4fStack(currentTexCoord);
+    @Getter private static int normalGeneration;
+    @Getter private static int texCoordGeneration;
+    @Getter private boolean enabled = false;
+    private int currentVertexFlags = VertexFlags.TEXTURE_BIT | VertexFlags.COLOR_BIT | VertexFlags.NORMAL_BIT;
+
+    private ShaderManager() {
+        vaoVertexFlags.defaultReturnValue(-1);
+        boolean isDev = false;
+        try {
+            final Object deobfEnv = Launch.blackboard != null ? Launch.blackboard.get("fml.deobfuscatedEnvironment") : null;
+            isDev = Boolean.TRUE.equals(deobfEnv);
+        } catch (Exception ignored) {}
+        if (isDev || Boolean.parseBoolean(System.getProperty("angelica.ffp.dumpShaders", "false"))) {
+            cache.setDumpDir(Paths.get("ffp_shaders"));
+        }
+    }
+
+    public static ShaderManager getInstance() {
+        return Holder.INSTANCE;
+    }
+
+    public void enable() {
+        enabled = true;
+
+        VertexFormat.registerSetupBufferStateOverride((format, offset) -> {
+            currentVertexFlags = format.getVertexFlags();
+            vaoVertexFlags.put(GLStateManager.getBoundVAO(), currentVertexFlags);
+            return false;
+        });
+
+        LOGGER.info("FFP shader emulation enabled");
+    }
+
+    public void disable() {
+        enabled = false;
+    }
+
+    public void activate() {
+        active = true;
+        updateVariant(true, true, true, true);
+        uploadUniforms();
+    }
+
+    public void deactivate() {
+        active = false;
+        currentProgram = null;
+        currentVertexKeyPacked = Long.MIN_VALUE;
+        currentFKLen = 0;
+    }
+
+
+
+    public void preDraw(boolean hasColor, boolean hasNormal, boolean hasTexCoord, boolean hasLightmap) {
+        GLStateManager.flushDeferredVertexAttribs();
+        BlendModeStorage.flushDeferredBlend();
+
+        if (!active) {
+            if (enabled) {
+                final int currentProgramId = GLStateManager.getActiveProgram();
+                if (currentProgramId != 0) {
+                    CompatUniformManager.onUseProgram(currentProgramId);
+                    return;
+                }
+                active = true;
+            } else {
+                return;
+            }
+        }
+
+        final long vkPacked = VertexKey.packFromState(hasColor, hasNormal, hasTexCoord, hasLightmap);
+        final int fkLen = FragmentKey.packFromState(currentFKScratch);
+
+        if (vkPacked != currentVertexKeyPacked || !Arrays.equals(currentFKScratch, 0, fkLen, currentFKPacked, 0, currentFKLen)) {
+            commitVariant(vkPacked, fkLen);
+        }
+
+        uploadUniforms();
+    }
+
+    public void preDraw(int vertexFlags) {
+        currentVertexFlags = vertexFlags;
+        preDraw(
+            (vertexFlags & VertexFlags.COLOR_BIT) != 0,
+            (vertexFlags & VertexFlags.NORMAL_BIT) != 0,
+            (vertexFlags & VertexFlags.TEXTURE_BIT) != 0,
+            (vertexFlags & VertexFlags.BRIGHTNESS_BIT) != 0
+        );
+    }
+
+    public void preDraw() {
+        preDraw(currentVertexFlags);
+    }
+
+    private void updateVariant(boolean hasColor, boolean hasNormal, boolean hasTexCoord, boolean hasLightmap) {
+        final long vkPacked = VertexKey.packFromState(hasColor, hasNormal, hasTexCoord, hasLightmap);
+        final int fkLen = FragmentKey.packFromState(currentFKScratch);
+        commitVariant(vkPacked, fkLen);
+    }
+
+    private void commitVariant(long vkPacked, int fkLen) {
+        currentVertexKeyPacked = vkPacked;
+        System.arraycopy(currentFKScratch, 0, currentFKPacked, 0, fkLen);
+        currentFKLen = fkLen;
+        currentProgram = cache.getOrCreate(vkPacked, currentFKPacked, currentFKLen);
+        GL20.glUseProgram(currentProgram.getProgramId());
+    }
+
+    private void uploadUniforms() {
+        if (currentProgram != null) {
+            uniforms.upload(currentProgram);
+        }
+    }
+
+    public static void setCurrentNormal(float x, float y, float z) {
+        currentNormal.set(x, y, z);
+        normalGeneration++;
+    }
+
+    public static void setCurrentTexCoord(float s, float t, float r, float q) {
+        currentTexCoord.set(s, t, r, q);
+        texCoordGeneration++;
+    }
+
+    public static void bumpNormalGeneration() { normalGeneration++; }
+    public static void bumpTexCoordGeneration() { texCoordGeneration++; }
+
+    public void enableClientVertexFlag(int flag)  { currentVertexFlags |= flag; }
+    public void disableClientVertexFlag(int flag) { currentVertexFlags &= ~flag; }
+    public int getCurrentVertexFlags() { return currentVertexFlags; }
+    public void setCurrentVertexFlags(int flags) { currentVertexFlags = flags; }
+
+    public void onBindVertexArray(int vaoId) {
+        final int flags = vaoVertexFlags.get(vaoId);
+        if (flags != -1) {
+            currentVertexFlags = flags;
+        }
+    }
+
+    public void onDeleteVertexArray(int vaoId) {
+        vaoVertexFlags.remove(vaoId);
+    }
+
+    public void destroy() {
+        cache.destroy();
+        uniforms.destroy();
+        TessellatorStreamingDrawer.destroy();
+        com.gtnewhorizons.angelica.glsm.QuadConverter.destroy();
+        active = false;
+        currentProgram = null;
+    }
+
+    public String getDebugInfo() {
+        return String.format("FFP: %d programs (%d vert, %d frag variants)",
+            cache.getProgramCount(), cache.getVertexVariantCount(), cache.getFragmentVariantCount());
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/TessellatorStreamingDrawer.java

@@ -0,0 +1,297 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.DirectTessellator;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.DefaultVertexFormat;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFlags;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.QuadConverter;
+import com.gtnewhorizons.angelica.glsm.RenderSystem;
+import com.gtnewhorizons.angelica.glsm.streaming.OrphanStreamingBuffer;
+import com.gtnewhorizons.angelica.glsm.streaming.PersistentStreamingBuffer;
+import net.minecraft.client.renderer.Tessellator;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL15;
+import org.lwjgl.opengl.GL30;
+
+import java.nio.ByteBuffer;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAddress0;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAlloc;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memFree;
+
+/**
+ * Replaces the vanilla Tessellator's FFP client-array draw path with a streaming VBO+VAO approach for GL 3.3 core profile compatibility.
+ * <p>
+ * Uses a persistent-mapped ring buffer on GL4.4+ hardware (zero-copy uploads with fence sync),
+ * falling back to the classic orphan pattern on older hardware or on overflow.
+ * Maintains two VAO sets (persistent + orphan) per vertex format (up to 16 combinations).
+ */
+public class TessellatorStreamingDrawer {
+
+    private static final Logger LOGGER = LogManager.getLogger("TessellatorStreamingDrawer");
+    private static final int FORMAT_COUNT = VertexFlags.BITSET_SIZE; // 16
+
+    private static PersistentStreamingBuffer persistentBuffer;
+    private static final OrphanStreamingBuffer[] orphanBuffers = new OrphanStreamingBuffer[FORMAT_COUNT];
+
+    private static final int[] persistentVAOs = new int[FORMAT_COUNT];
+    private static final int[] orphanVAOs = new int[FORMAT_COUNT];
+
+    private static ByteBuffer repackBuffer;
+    private static long repackAddress;
+    private static int repackCapacity;
+
+    private static boolean initialized = false;
+
+    static {
+        // Initial repack buffer: 64KB
+        repackCapacity = 0x10000;
+        repackBuffer = memAlloc(repackCapacity);
+        repackAddress = memAddress0(repackBuffer);
+    }
+
+    private static void init() {
+        if (initialized) return;
+        initialized = true;
+
+        if (RenderSystem.supportsBufferStorage() && !Boolean.getBoolean("angelica.forceOrphanStreaming")) {
+            try {
+                persistentBuffer = new PersistentStreamingBuffer();
+                LOGGER.info("Persistent streaming buffer created ({}MB)", PersistentStreamingBuffer.DEFAULT_CAPACITY / (1024 * 1024));
+            } catch (Exception e) {
+                LOGGER.warn("Failed to create persistent streaming buffer, using orphan fallback", e);
+                persistentBuffer = null;
+            }
+        }
+    }
+
+    /**
+     * Draw the vanilla Tessellator's data using streaming VBO+VAO instead of FFP client arrays.
+     */
+    public static int draw(Tessellator tess) {
+        if (!tess.isDrawing) {
+            throw new IllegalStateException("Not tesselating!");
+        }
+
+        tess.isDrawing = false;
+
+        final int vertexCount = tess.vertexCount;
+        if (vertexCount == 0) {
+            final int result = tess.rawBufferIndex * 4;
+            tess.reset();
+            return result;
+        }
+
+        // Determine the optimal vertex format from the tessellator's flags
+        final int flags = VertexFlags.convertToFlags(tess.hasTexture, tess.hasColor, tess.hasNormals, tess.hasBrightness);
+        final VertexFormat format = DefaultVertexFormat.ALL_FORMATS[flags];
+        final int vertexSize = format.getVertexSize();
+
+        final int requiredBytes = vertexCount * vertexSize;
+        ensureRepackCapacity(requiredBytes);
+
+        final long writePtr = format.writeToBuffer0(repackAddress, tess.rawBuffer, tess.rawBufferIndex);
+        repackBuffer.position(0);
+        repackBuffer.limit((int)(writePtr - repackAddress));
+
+        uploadAndDraw(repackBuffer, flags, format, vertexSize, tess.drawMode, vertexCount);
+
+        // Shrink rawBuffer if oversized
+        if (tess.rawBufferSize > 0x20000 && tess.rawBufferIndex < (tess.rawBufferSize << 3)) {
+            tess.rawBufferSize = 0x10000;
+            tess.rawBuffer = new int[tess.rawBufferSize];
+        }
+
+        final int result = tess.rawBufferIndex * 4;
+        tess.reset();
+        return result;
+    }
+
+    /**
+     * Draw DirectTessellator data via streaming VBO+VAO. Used for live immediate mode emulation.
+     */
+    public static void drawDirect(DirectTessellator dt) {
+        final VertexFormat format = dt.getVertexFormat();
+        if (format == null) return;
+
+        final int vertexCount = dt.getVertexCount();
+        if (vertexCount == 0) return;
+
+        final int drawMode = dt.getDrawMode();
+        final int flags = format.getVertexFlags();
+        final ByteBuffer buffer = dt.getWriteBuffer();
+        final int vertexSize = format.getVertexSize();
+
+        uploadAndDraw(buffer, flags, format, vertexSize, drawMode, vertexCount);
+    }
+
+    private static String cachedDebugInfo = "Stream: not initialized";
+    private static long lastDebugUpdateNanos;
+    private static final long DEBUG_UPDATE_INTERVAL_NS = 500_000_000L; // 500ms
+
+    public static String getDebugInfo() {
+        if (!initialized) return "Stream: not initialized";
+
+        final long now = System.nanoTime();
+        if (now - lastDebugUpdateNanos < DEBUG_UPDATE_INTERVAL_NS) {
+            return cachedDebugInfo;
+        }
+        lastDebugUpdateNanos = now;
+
+        int orphanCount = 0;
+        int orphanBytes = 0;
+        for (int i = 0; i < FORMAT_COUNT; i++) {
+            if (orphanBuffers[i] != null) {
+                orphanCount++;
+                orphanBytes += orphanBuffers[i].getCapacity();
+            }
+        }
+
+        if (persistentBuffer != null) {
+            cachedDebugInfo = String.format("Stream: Persistent %s (%s free) + %d orphan (%s)",
+                formatBytes(persistentBuffer.getCapacity()), formatBytes(persistentBuffer.getRemaining()),
+                orphanCount, formatBytes(orphanBytes));
+        } else {
+            cachedDebugInfo = String.format("Stream: Orphan (%d bufs, %s)", orphanCount, formatBytes(orphanBytes));
+        }
+        return cachedDebugInfo;
+    }
+
+    private static String formatBytes(int bytes) {
+        if (bytes >= 1024 * 1024) return String.format("%5.1fMB", bytes / (1024.0 * 1024.0));
+        if (bytes >= 1024) return String.format("%5.1fKB", bytes / 1024.0);
+        return String.format("%5dB", bytes);
+    }
+
+    public static void endFrame() {
+        if (persistentBuffer != null) {
+            persistentBuffer.postDraw();
+        }
+    }
+
+    /**
+     * Draw a merged batch of pre-packed vertex data from a DeferredBatchTessellator.
+     * Copies byte ranges into repackBuffer, then uploads and draws.
+     */
+    static void drawPackedBatch(DeferredBatchTessellator source,
+                                java.util.List<DeferredBatchTessellator.DrawRange> ranges,
+                                int from, int to,
+                                int totalBytes, int totalVertices,
+                                int drawMode, int flags) {
+        if (totalVertices == 0) return;
+
+        final VertexFormat format = DefaultVertexFormat.ALL_FORMATS[flags];
+        final int vertexSize = format.getVertexSize();
+
+        ensureRepackCapacity(totalBytes);
+
+        long writePos = repackAddress;
+        for (int j = from; j < to; j++) {
+            final DeferredBatchTessellator.DrawRange r = ranges.get(j);
+            source.copyRange(r.byteOffset(), r.byteLength(), writePos);
+            writePos += r.byteLength();
+        }
+        repackBuffer.position(0);
+        repackBuffer.limit(totalBytes);
+
+        uploadAndDraw(repackBuffer, flags, format, vertexSize, drawMode, totalVertices);
+    }
+
+    /**
+     * Upload packed vertex data to a streaming buffer and issue the draw call.
+     * Tries the persistent ring buffer first, falls back to orphan buffer on overflow.
+     */
+    private static void uploadAndDraw(ByteBuffer packed, int flags, VertexFormat format, int vertexSize, int drawMode, int vertexCount) {
+        ensureVAO(flags, format);
+
+        int firstVertex = -1;
+
+        if (persistentBuffer != null) {
+            firstVertex = persistentBuffer.upload(packed, vertexSize);
+        }
+
+        if (firstVertex >= 0) {
+            GLStateManager.glBindVertexArray(persistentVAOs[flags]);
+        } else {
+            GLStateManager.glBindVertexArray(orphanVAOs[flags]);
+            orphanBuffers[flags].upload(packed);
+            firstVertex = 0;
+        }
+
+        GLStateManager.prepareWideLineEmulation(drawMode);
+        ShaderManager.getInstance().preDraw(flags);
+        drawWithQuadConversion(drawMode, firstVertex, vertexCount);
+        GLStateManager.glBindVertexArray(0);
+    }
+
+    private static void drawWithQuadConversion(int drawMode, int firstVertex, int vertexCount) {
+        if (drawMode == GL11.GL_QUADS) {
+            QuadConverter.drawQuadsAsTriangles(firstVertex, vertexCount);
+        } else {
+            GL11.glDrawArrays(drawMode, firstVertex, vertexCount);
+        }
+    }
+
+    private static void ensureRepackCapacity(int requiredBytes) {
+        if (requiredBytes <= repackCapacity) return;
+
+        int newCapacity = repackCapacity;
+        while (newCapacity < requiredBytes) {
+            newCapacity *= 2;
+        }
+
+        memFree(repackBuffer);
+        repackBuffer = memAlloc(newCapacity);
+        repackAddress = memAddress0(repackBuffer);
+        repackCapacity = newCapacity;
+    }
+
+    private static void ensureVAO(int flags, VertexFormat format) {
+        init();
+
+        if (orphanVAOs[flags] == 0) {
+            orphanBuffers[flags] = new OrphanStreamingBuffer();
+
+            orphanVAOs[flags] = GL30.glGenVertexArrays();
+            GLStateManager.glBindVertexArray(orphanVAOs[flags]);
+            GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, orphanBuffers[flags].getBufferId());
+            format.setupBufferState(0L);
+            GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
+            GLStateManager.glBindVertexArray(0);
+        }
+
+        if (persistentBuffer != null && persistentVAOs[flags] == 0) {
+            persistentVAOs[flags] = GL30.glGenVertexArrays();
+            GLStateManager.glBindVertexArray(persistentVAOs[flags]);
+            GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, persistentBuffer.getBufferId());
+            format.setupBufferState(0L);
+            GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
+            GLStateManager.glBindVertexArray(0);
+        }
+    }
+
+    /**
+     * Clean up all VAOs, streaming buffers, and the repack buffer.
+     */
+    public static void destroy() {
+        for (int i = 0; i < FORMAT_COUNT; i++) {
+            if (persistentVAOs[i] != 0) { GLStateManager.glDeleteVertexArrays(persistentVAOs[i]); persistentVAOs[i] = 0; }
+            if (orphanVAOs[i] != 0) { GLStateManager.glDeleteVertexArrays(orphanVAOs[i]); orphanVAOs[i] = 0; }
+            if (orphanBuffers[i] != null) { orphanBuffers[i].destroy(); orphanBuffers[i] = null; }
+        }
+        if (persistentBuffer != null) {
+            persistentBuffer.destroy();
+            persistentBuffer = null;
+        }
+        if (repackBuffer != null) {
+            memFree(repackBuffer);
+            repackBuffer = null;
+            repackAddress = 0;
+            repackCapacity = 0;
+        }
+        initialized = false;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/Uniforms.java

@@ -0,0 +1,494 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.states.ClipPlaneState;
+import com.gtnewhorizons.angelica.glsm.states.FogState;
+import com.gtnewhorizons.angelica.glsm.states.LightState;
+import com.gtnewhorizons.angelica.glsm.states.MaterialState;
+import com.gtnewhorizons.angelica.glsm.states.TexGenState;
+import net.minecraft.client.renderer.OpenGlHelper;
+import org.joml.Matrix3f;
+import org.joml.Matrix4f;
+import org.joml.Vector4f;
+import org.lwjgl.opengl.GL20;
+
+import java.nio.FloatBuffer;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAllocFloat;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memFree;
+
+/**
+ * Uploads GLSM cached state to the active FFP program's uniforms.
+ *
+ * Follows Mesa's prog_statevars.c patterns:
+ * - Pre-computed derived state (light products, scene color) when material is static
+ * - Raw light/material values when color material is active
+ * - Optimized fog params (pre-divided for single MAD in shader)
+ */
+public class Uniforms {
+    // Reusable temp buffers for uniform upload
+    private final FloatBuffer mat4Buf = memAllocFloat(16);
+    private final FloatBuffer mat3Buf = memAllocFloat(9);
+    private final FloatBuffer vec4Buf = memAllocFloat(4);
+    private final FloatBuffer vec3Buf = memAllocFloat(3);
+    private final FloatBuffer clipPlaneBuf = memAllocFloat(32); // 8 planes * vec4
+
+    // Derived matrices (computed on CPU)
+    private final Matrix4f mvpMatrix = new Matrix4f();
+    private final Matrix3f normalMatrix = new Matrix3f();
+
+    // Temp vectors for light product and normal scale computation
+    private final Vector4f tempVec4 = new Vector4f();
+    private final org.joml.Vector3f tempVec3 = new org.joml.Vector3f();
+
+    // Pre-computed constants for fog params (Mesa STATE_FOG_PARAMS_OPTIMIZED)
+    private static final double LN2 = Math.log(2.0);
+    private static final double SQRT_LN2 = Math.sqrt(LN2);
+
+    // Dirty tracking: last-uploaded generation per category + program ID.
+    // Program change forces full re-upload since uniform locations differ.
+    private int lastProgramId = -1;
+    private int lastMvGen = -1;
+    private int lastProjGen = -1;
+    private int lastTexMatGen = -1;
+    private int lastLightingGen = -1;
+    private int lastFragmentGen = -1;
+    private int lastColorGen = -1;
+    private int lastNormalGen = -1;
+    private int lastTexCoordGen = -1;
+    private float lastLightmapX = Float.NaN;
+    private float lastLightmapY = Float.NaN;
+    private int lastTexGenGen = -1;
+    private int lastClipPlaneGen = -1;
+    private float lastLineWidth = Float.NaN;
+    private int lastViewportWidth = -1;
+    private int lastViewportHeight = -1;
+
+    /**
+     * Upload all relevant uniforms to the given FFP program based on current GLSM state.
+     * Uses generation counters to skip categories that haven't changed since last upload.
+     */
+    public void upload(Program program) {
+        final boolean programChanged = program.getProgramId() != lastProgramId;
+        lastProgramId = program.getProgramId();
+
+        final int mvGen = GLStateManager.mvGeneration;
+        final int projGen = GLStateManager.projGeneration;
+        final int texMatGen = GLStateManager.texMatrixGeneration;
+        final boolean mvChanged = programChanged || mvGen != lastMvGen;
+        final boolean projChanged = programChanged || projGen != lastProjGen;
+        final boolean texMatChanged = programChanged || texMatGen != lastTexMatGen;
+        if (mvChanged || projChanged || texMatChanged) {
+            uploadMatrices(program, mvChanged, projChanged, texMatChanged);
+            lastMvGen = mvGen;
+            lastProjGen = projGen;
+            lastTexMatGen = texMatGen;
+        }
+
+        if (program.getVertexKey().lightingEnabled()) {
+            final int litGen = GLStateManager.lightingGeneration;
+            if (programChanged || litGen != lastLightingGen) {
+                uploadLighting(program);
+                lastLightingGen = litGen;
+            }
+        }
+
+        // Current color/normal/texcoord — skip if generation unchanged
+        if (!program.getVertexKey().hasVertexColor()) {
+            final int colorGen = GLStateManager.colorGeneration;
+            if (programChanged || colorGen != lastColorGen) {
+                uploadCurrentColor(program);
+                lastColorGen = colorGen;
+            }
+        }
+
+        if (!program.getVertexKey().hasVertexNormal() && program.getVertexKey().lightingEnabled()) {
+            final int normalGen = ShaderManager.getNormalGeneration();
+            if (programChanged || normalGen != lastNormalGen) {
+                uploadCurrentNormal(program);
+                lastNormalGen = normalGen;
+            }
+        }
+
+        if (!program.getVertexKey().hasVertexTexCoord() && program.getVertexKey().textureEnabled()) {
+            final int texGen = ShaderManager.getTexCoordGeneration();
+            if (programChanged || texGen != lastTexCoordGen) {
+                uploadCurrentTexCoord(program);
+                lastTexCoordGen = texGen;
+            }
+        }
+
+        if (program.getVertexKey().lightmapEnabled() && !program.getVertexKey().hasVertexLightmap()) {
+            if (programChanged || OpenGlHelper.lastBrightnessX != lastLightmapX || OpenGlHelper.lastBrightnessY != lastLightmapY) {
+                uploadCurrentLightmapCoord(program);
+                lastLightmapX = OpenGlHelper.lastBrightnessX;
+                lastLightmapY = OpenGlHelper.lastBrightnessY;
+            }
+        }
+
+        if (program.getVertexKey().texGenEnabled()) {
+            final int tgGen = GLStateManager.texGenGeneration;
+            if (programChanged || tgGen != lastTexGenGen) {
+                uploadTexGen(program);
+                lastTexGenGen = tgGen;
+            }
+        }
+
+        if (program.getVertexKey().clipPlanesEnabled()) {
+            final int cpGen = GLStateManager.clipPlaneGeneration;
+            if (programChanged || cpGen != lastClipPlaneGen) {
+                uploadClipPlanes(program);
+                lastClipPlaneGen = cpGen;
+            }
+        }
+
+        final int fragGen = GLStateManager.fragmentGeneration;
+        if (programChanged || fragGen != lastFragmentGen) {
+            uploadFragmentUniforms(program);
+            lastFragmentGen = fragGen;
+        }
+
+        // Wide line emulation uniforms
+        if (program.locLineWidth != -1 && program.locViewportSize != -1) {
+            uploadWideLineUniforms(program, programChanged);
+        }
+    }
+
+    private void uploadMatrices(Program program, boolean mvChanged, boolean projChanged, boolean texMatChanged) {
+        final Matrix4f mv = GLStateManager.getModelViewMatrix();
+        final Matrix4f proj = GLStateManager.getProjectionMatrix();
+
+        // ModelView + derived (normal matrix, normal scale)
+        if (mvChanged) {
+            if (program.locModelViewMatrix != -1) {
+                mv.get(mat4Buf);
+                GL20.glUniformMatrix4(program.locModelViewMatrix, false, mat4Buf);
+            }
+
+            // Normal matrix = inverse transpose of upper-left 3x3 of ModelView
+            if (program.locNormalMatrix != -1 || program.locNormalScale != -1) {
+                mv.normal(normalMatrix);
+            }
+            if (program.locNormalMatrix != -1) {
+                normalMatrix.get(mat3Buf);
+                GL20.glUniformMatrix3(program.locNormalMatrix, false, mat3Buf);
+            }
+
+            // Normal scale (for GL_RESCALE_NORMAL without GL_NORMALIZE)
+            if (program.locNormalScale != -1) {
+                // Scale factor = 1/length of first column of normal matrix
+                final float scale = 1.0f / normalMatrix.getColumn(0, tempVec3).length();
+                GL20.glUniform1f(program.locNormalScale, scale);
+            }
+        }
+
+        // Projection
+        if (projChanged) {
+            if (program.locProjectionMatrix != -1) {
+                proj.get(mat4Buf);
+                GL20.glUniformMatrix4(program.locProjectionMatrix, false, mat4Buf);
+            }
+        }
+
+        // MVP = Projection * ModelView — needs recompute if either input changed
+        if ((mvChanged || projChanged) && program.locMVPMatrix != -1) {
+            proj.mul(mv, mvpMatrix);
+            mvpMatrix.get(mat4Buf);
+            GL20.glUniformMatrix4(program.locMVPMatrix, false, mat4Buf);
+        }
+
+        // Texture matrices
+        if (texMatChanged) {
+            // Texture matrix unit 0
+            if (program.locTextureMatrix0 != -1) {
+                final Matrix4f texMat = GLStateManager.getTextures().getTextureUnitMatrix(0);
+                texMat.get(mat4Buf);
+                GL20.glUniformMatrix4(program.locTextureMatrix0, false, mat4Buf);
+            }
+
+            // Texture matrix unit 1 (lightmap)
+            if (program.locLightmapTextureMatrix != -1) {
+                final Matrix4f lmTexMat = GLStateManager.getTextures().getTextureUnitMatrix(1);
+                lmTexMat.get(mat4Buf);
+                GL20.glUniformMatrix4(program.locLightmapTextureMatrix, false, mat4Buf);
+            }
+        }
+    }
+
+    private void uploadLighting(Program program) {
+        final VertexKey vk = program.getVertexKey();
+
+        if (vk.colorMaterialEnabled()) {
+            uploadLightingColorMaterial(program, vk);
+        } else {
+            uploadLightingPreComputed(program, vk);
+        }
+    }
+
+    /**
+     * Color material active: upload raw light and material values.
+     * The shader multiplies them with vertex color at runtime.
+     */
+    private void uploadLightingColorMaterial(Program program, VertexKey vk) {
+        final MaterialState mat = GLStateManager.getFrontMaterial();
+
+        uploadVec4(program.locLightModelAmbient, GLStateManager.getLightModel().ambient);
+        uploadVec4(program.locMaterialEmission, mat.emission);
+        uploadVec4(program.locMaterialAmbient, mat.ambient);
+        uploadVec4(program.locMaterialDiffuse, mat.diffuse);
+        uploadVec4(program.locMaterialSpecular, mat.specular);
+        if (program.locMaterialShininess != -1) {
+            GL20.glUniform1f(program.locMaterialShininess, mat.shininess);
+        }
+
+        if (vk.light0Enabled()) {
+            final LightState light0 = GLStateManager.getLightDataStates()[0];
+            uploadVec4(program.locLight0Ambient, light0.ambient);
+            uploadVec4(program.locLight0Diffuse, light0.diffuse);
+            uploadVec4(program.locLight0Specular, light0.specular);
+            uploadVec4(program.locLight0Position, light0.position);
+        }
+        if (vk.light1Enabled()) {
+            final LightState light1 = GLStateManager.getLightDataStates()[1];
+            uploadVec4(program.locLight1Ambient, light1.ambient);
+            uploadVec4(program.locLight1Diffuse, light1.diffuse);
+            uploadVec4(program.locLight1Specular, light1.specular);
+            uploadVec4(program.locLight1Position, light1.position);
+        }
+    }
+
+    /**
+     * No color material: upload pre-computed light products and scene color.
+     * Fewer shader multiplies since material is static.
+     */
+    private void uploadLightingPreComputed(Program program, VertexKey vk) {
+        final MaterialState mat = GLStateManager.getFrontMaterial();
+
+        // Scene color = emission + ambient * lightModel.ambient
+        // Alpha = material.diffuse.a
+        if (program.locSceneColor != -1) {
+            tempVec4.set(
+                mat.emission.x + mat.ambient.x * GLStateManager.getLightModel().ambient.x,
+                mat.emission.y + mat.ambient.y * GLStateManager.getLightModel().ambient.y,
+                mat.emission.z + mat.ambient.z * GLStateManager.getLightModel().ambient.z,
+                mat.diffuse.w  // alpha from diffuse
+            );
+            uploadVec4(program.locSceneColor, tempVec4);
+        }
+
+        if (program.locMaterialShininess != -1) {
+            GL20.glUniform1f(program.locMaterialShininess, mat.shininess);
+        }
+
+        // Per-light products
+        if (vk.light0Enabled()) {
+            final LightState light0 = GLStateManager.getLightDataStates()[0];
+            uploadVec4(program.locLight0Position, light0.position);
+            uploadLightProduct(program.locLightProd0Ambient, light0.ambient, mat.ambient);
+            uploadLightProduct(program.locLightProd0Diffuse, light0.diffuse, mat.diffuse);
+            uploadLightProduct(program.locLightProd0Specular, light0.specular, mat.specular);
+        }
+        if (vk.light1Enabled()) {
+            final LightState light1 = GLStateManager.getLightDataStates()[1];
+            uploadVec4(program.locLight1Position, light1.position);
+            uploadLightProduct(program.locLightProd1Ambient, light1.ambient, mat.ambient);
+            uploadLightProduct(program.locLightProd1Diffuse, light1.diffuse, mat.diffuse);
+            uploadLightProduct(program.locLightProd1Specular, light1.specular, mat.specular);
+        }
+    }
+
+    /**
+     * Upload pre-multiplied light product: light.X * material.X (RGB only).
+     */
+    private void uploadLightProduct(int loc, Vector4f lightVal, Vector4f materialVal) {
+        if (loc == -1) return;
+        vec3Buf.clear();
+        vec3Buf.put(lightVal.x * materialVal.x);
+        vec3Buf.put(lightVal.y * materialVal.y);
+        vec3Buf.put(lightVal.z * materialVal.z);
+        vec3Buf.flip();
+        GL20.glUniform3(loc, vec3Buf);
+    }
+
+    private void uploadCurrentColor(Program program) {
+        if (program.locCurrentColor == -1) return;
+        // Upload the current color from GLSM
+        final var color = GLStateManager.getColor();
+        vec4Buf.clear();
+        vec4Buf.put(color.getRed());
+        vec4Buf.put(color.getGreen());
+        vec4Buf.put(color.getBlue());
+        vec4Buf.put(color.getAlpha());
+        vec4Buf.flip();
+        GL20.glUniform4(program.locCurrentColor, vec4Buf);
+    }
+
+    private void uploadCurrentTexCoord(Program program) {
+        if (program.locCurrentTexCoord == -1) return;
+        final var tc = ShaderManager.getCurrentTexCoord();
+        uploadVec4(program.locCurrentTexCoord, tc);
+    }
+
+    private void uploadCurrentLightmapCoord(Program program) {
+        if (program.locCurrentLightmapCoord == -1) return;
+        GL20.glUniform2f(program.locCurrentLightmapCoord,
+            OpenGlHelper.lastBrightnessX, OpenGlHelper.lastBrightnessY);
+    }
+
+    private void uploadCurrentNormal(Program program) {
+        if (program.locCurrentNormal == -1) return;
+        // Upload current normal from FFPShaderManager's tracked normal
+        final var normal = ShaderManager.getCurrentNormal();
+        vec3Buf.clear();
+        vec3Buf.put(normal.x);
+        vec3Buf.put(normal.y);
+        vec3Buf.put(normal.z);
+        vec3Buf.flip();
+        GL20.glUniform3(program.locCurrentNormal, vec3Buf);
+    }
+
+    private void uploadTexGen(Program program) {
+        final VertexKey vk = program.getVertexKey();
+        final TexGenState tg = GLStateManager.getTextures().getTexGenState(0);
+
+        if (vk.texGenModeS() == VertexKey.TG_OBJ_LINEAR) {
+            uploadPlane(program.locTexGenObjPlaneS, tg.getObjectPlane(org.lwjgl.opengl.GL11.GL_S));
+        } else if (vk.texGenModeS() == VertexKey.TG_EYE_LINEAR) {
+            uploadPlane(program.locTexGenEyePlaneS, tg.getEyePlane(org.lwjgl.opengl.GL11.GL_S));
+        }
+
+        if (vk.texGenModeT() == VertexKey.TG_OBJ_LINEAR) {
+            uploadPlane(program.locTexGenObjPlaneT, tg.getObjectPlane(org.lwjgl.opengl.GL11.GL_T));
+        } else if (vk.texGenModeT() == VertexKey.TG_EYE_LINEAR) {
+            uploadPlane(program.locTexGenEyePlaneT, tg.getEyePlane(org.lwjgl.opengl.GL11.GL_T));
+        }
+
+        if (vk.texGenModeR() == VertexKey.TG_OBJ_LINEAR) {
+            uploadPlane(program.locTexGenObjPlaneR, tg.getObjectPlane(org.lwjgl.opengl.GL11.GL_R));
+        } else if (vk.texGenModeR() == VertexKey.TG_EYE_LINEAR) {
+            uploadPlane(program.locTexGenEyePlaneR, tg.getEyePlane(org.lwjgl.opengl.GL11.GL_R));
+        }
+
+        if (vk.texGenModeQ() == VertexKey.TG_OBJ_LINEAR) {
+            uploadPlane(program.locTexGenObjPlaneQ, tg.getObjectPlane(org.lwjgl.opengl.GL11.GL_Q));
+        } else if (vk.texGenModeQ() == VertexKey.TG_EYE_LINEAR) {
+            uploadPlane(program.locTexGenEyePlaneQ, tg.getEyePlane(org.lwjgl.opengl.GL11.GL_Q));
+        }
+    }
+
+    private void uploadPlane(int loc, float[] plane) {
+        if (loc == -1) return;
+        vec4Buf.clear();
+        vec4Buf.put(plane[0]);
+        vec4Buf.put(plane[1]);
+        vec4Buf.put(plane[2]);
+        vec4Buf.put(plane[3]);
+        vec4Buf.flip();
+        GL20.glUniform4(loc, vec4Buf);
+    }
+
+    private void uploadClipPlanes(Program program) {
+        if (program.locClipPlanes == -1) return;
+        final ClipPlaneState cps = GLStateManager.getClipPlaneState();
+        clipPlaneBuf.clear();
+        for (int i = 0; i < GLStateManager.MAX_CLIP_PLANES; i++) {
+            cps.putEyePlane(i, clipPlaneBuf);
+        }
+        clipPlaneBuf.flip();
+        GL20.glUniform4(program.locClipPlanes, clipPlaneBuf);
+    }
+
+    private void uploadFragmentUniforms(Program program) {
+        final FragmentKey fk = program.getFragmentKey();
+
+        // Alpha test reference
+        if (fk.alphaTestEnabled() && program.locAlphaRef != -1) {
+            GL20.glUniform1f(program.locAlphaRef, GLStateManager.getAlphaState().getReference());
+        }
+
+        // Per-unit tex env color
+        for (int i = 0; i < 4; i++) {
+            if (program.locTexEnvColor[i] != -1) {
+                final var envState = GLStateManager.getTextures().getTexEnvState(i);
+                vec4Buf.clear();
+                vec4Buf.put(envState.envColorR);
+                vec4Buf.put(envState.envColorG);
+                vec4Buf.put(envState.envColorB);
+                vec4Buf.put(envState.envColorA);
+                vec4Buf.flip();
+                GL20.glUniform4(program.locTexEnvColor[i], vec4Buf);
+            }
+        }
+
+        // Fog
+        if (fk.fogMode() != FragmentKey.FOG_NONE) {
+            uploadFog(program);
+        }
+    }
+
+    /**
+     * Upload optimized fog params (following Mesa's STATE_FOG_PARAMS_OPTIMIZED):
+     */
+    private void uploadFog(Program program) {
+        final FogState fog = GLStateManager.getFogState();
+
+        if (program.locFogParams != -1) {
+            final float start = fog.getStart();
+            final float end = fog.getEnd();
+            final float density = fog.getDensity();
+            final float range = end - start;
+
+            vec4Buf.clear();
+            vec4Buf.put(range != 0.0f ? -1.0f / range : 0.0f);     // [0]: -1/(end-start)
+            vec4Buf.put(range != 0.0f ? end / range : 1.0f);         // [1]: end/(end-start)
+            vec4Buf.put((float)(density / LN2));        // [2]: density/ln(2)
+            vec4Buf.put((float)(density / SQRT_LN2));  // [3]: density/sqrt(ln(2))
+            vec4Buf.flip();
+            GL20.glUniform4(program.locFogParams, vec4Buf);
+        }
+
+        if (program.locFogColor != -1) {
+            vec4Buf.clear();
+            vec4Buf.put((float) fog.getFogColor().x);
+            vec4Buf.put((float) fog.getFogColor().y);
+            vec4Buf.put((float) fog.getFogColor().z);
+            vec4Buf.put(fog.getFogAlpha());
+            vec4Buf.flip();
+            GL20.glUniform4(program.locFogColor, vec4Buf);
+        }
+    }
+
+    private void uploadWideLineUniforms(Program program, boolean programChanged) {
+        final float lineWidth = GLStateManager.getLineState().getWidth();
+        if (programChanged || lineWidth != lastLineWidth) {
+            GL20.glUniform1f(program.locLineWidth, lineWidth);
+            lastLineWidth = lineWidth;
+        }
+        final int vw = GLStateManager.getViewportState().width;
+        final int vh = GLStateManager.getViewportState().height;
+        if (programChanged || vw != lastViewportWidth || vh != lastViewportHeight) {
+            GL20.glUniform2f(program.locViewportSize, vw, vh);
+            lastViewportWidth = vw;
+            lastViewportHeight = vh;
+        }
+    }
+
+    private void uploadVec4(int loc, Vector4f v) {
+        if (loc == -1) return;
+        vec4Buf.clear();
+        vec4Buf.put(v.x);
+        vec4Buf.put(v.y);
+        vec4Buf.put(v.z);
+        vec4Buf.put(v.w);
+        vec4Buf.flip();
+        GL20.glUniform4(loc, vec4Buf);
+    }
+
+    public void destroy() {
+        memFree(mat4Buf);
+        memFree(mat3Buf);
+        memFree(vec4Buf);
+        memFree(vec3Buf);
+        memFree(clipPlaneBuf);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/VertexKey.java

@@ -0,0 +1,265 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizons.angelica.glsm.DisplayListManager;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import com.gtnewhorizons.angelica.glsm.states.TexGenState;
+import org.joml.Matrix4f;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL12;
+
+/**
+ * Compact key capturing the vertex shader permutation axes for FFP emulation.
+ * Packed into a single long for fast hash/compare.
+ */
+public final class VertexKey {
+
+    private final long packed;
+
+    private static final int BIT_LIGHTING            = 0;
+    private static final int BIT_LIGHT0              = 1;
+    private static final int BIT_LIGHT1              = 2;
+    private static final int BIT_LIGHT0_DIR          = 3;
+    private static final int BIT_LIGHT1_DIR          = 4;
+    private static final int BIT_COLOR_MATERIAL      = 5;
+    private static final int BIT_SEPARATE_SPECULAR   = 6;
+    private static final int BIT_FOG                 = 7;
+    private static final int BIT_FOG_DIST_MODE       = 8;
+    private static final int BIT_NORMALIZE           = 10;
+    private static final int BIT_RESCALE_NORMAL      = 11;
+    private static final int BIT_TEXTURE             = 12;
+    private static final int BIT_LIGHTMAP            = 13;
+    private static final int BIT_TEX_MATRIX          = 14;
+    private static final int BIT_HAS_VERTEX_COLOR    = 15;
+    private static final int BIT_HAS_VERTEX_NORMAL   = 16;
+    private static final int BIT_HAS_VERTEX_TEX      = 17;
+    private static final int BIT_HAS_VERTEX_LIGHTMAP = 18;
+    private static final int BIT_COLOR_MAT_MODE      = 19;
+    // bits 19-21: colorMaterialMode (3 bits)
+    // TexGen modes: 3 bits each (0=NONE, 1=OBJ_LINEAR, 2=EYE_LINEAR)
+    private static final int BIT_TEXGEN_S            = 22;
+    private static final int BIT_TEXGEN_T            = 25;
+    private static final int BIT_TEXGEN_R            = 28;
+    private static final int BIT_TEXGEN_Q            = 31;
+    // bits 31-33: texGenModeQ (3 bits)
+    private static final int BIT_CLIP_PLANES         = 34;
+    private static final int BIT_WIDE_LINE           = 35;
+
+    public static final int TG_NONE                  = 0;
+    public static final int TG_OBJ_LINEAR            = 1;
+    public static final int TG_EYE_LINEAR            = 2;
+
+    public static final int CM_AMBIENT               = 0;
+    public static final int CM_DIFFUSE               = 1;
+    public static final int CM_SPECULAR              = 2;
+    public static final int CM_EMISSION              = 3;
+    public static final int CM_AMBIENT_AND_DIFFUSE   = 4;
+
+    private VertexKey(long packed) {
+        this.packed = packed;
+    }
+
+    public long pack() { return packed; }
+
+    public boolean lightingEnabled()       { return bit(BIT_LIGHTING); }
+    public boolean light0Enabled()         { return bit(BIT_LIGHT0); }
+    public boolean light1Enabled()         { return bit(BIT_LIGHT1); }
+    public boolean light0Directional()     { return bit(BIT_LIGHT0_DIR); }
+    public boolean light1Directional()     { return bit(BIT_LIGHT1_DIR); }
+    public boolean colorMaterialEnabled()  { return bit(BIT_COLOR_MATERIAL); }
+    public boolean separateSpecular()      { return bit(BIT_SEPARATE_SPECULAR); }
+    public boolean fogEnabled()            { return bit(BIT_FOG); }
+    public int fogDistanceMode()           { return (int)((packed >> BIT_FOG_DIST_MODE) & 0x3); }
+    public boolean normalizeEnabled()      { return bit(BIT_NORMALIZE); }
+    public boolean rescaleNormalsEnabled() { return bit(BIT_RESCALE_NORMAL); }
+    public boolean textureEnabled()        { return bit(BIT_TEXTURE); }
+    public boolean lightmapEnabled()       { return bit(BIT_LIGHTMAP); }
+    public boolean textureMatrixEnabled()  { return bit(BIT_TEX_MATRIX); }
+    public boolean hasVertexColor()        { return bit(BIT_HAS_VERTEX_COLOR); }
+    public boolean hasVertexNormal()       { return bit(BIT_HAS_VERTEX_NORMAL); }
+    public boolean hasVertexTexCoord()     { return bit(BIT_HAS_VERTEX_TEX); }
+    public boolean hasVertexLightmap()    { return bit(BIT_HAS_VERTEX_LIGHTMAP); }
+    /** Color material mode (CM_AMBIENT, CM_DIFFUSE, CM_SPECULAR, CM_EMISSION, CM_AMBIENT_AND_DIFFUSE). Only meaningful when colorMaterialEnabled(). */
+    public int colorMaterialMode()        { return (int)((packed >> BIT_COLOR_MAT_MODE) & 0x7); }
+
+    /** TexGen mode for S coordinate (TG_NONE, TG_OBJ_LINEAR, TG_EYE_LINEAR). */
+    public int texGenModeS()              { return (int)((packed >> BIT_TEXGEN_S) & 0x7); }
+    /** TexGen mode for T coordinate. */
+    public int texGenModeT()              { return (int)((packed >> BIT_TEXGEN_T) & 0x7); }
+    /** TexGen mode for R coordinate. */
+    public int texGenModeR()              { return (int)((packed >> BIT_TEXGEN_R) & 0x7); }
+    /** TexGen mode for Q coordinate. */
+    public int texGenModeQ()              { return (int)((packed >> BIT_TEXGEN_Q) & 0x7); }
+    /** Whether any texgen coordinate is enabled. */
+    public boolean texGenEnabled()        { return texGenModeS() != TG_NONE || texGenModeT() != TG_NONE || texGenModeR() != TG_NONE || texGenModeQ() != TG_NONE; }
+    /** Whether any clip plane is enabled. */
+    public boolean clipPlanesEnabled()    { return bit(BIT_CLIP_PLANES); }
+    /** Whether wide line GS emulation is active for this variant. */
+    public boolean wideLineEmulation()   { return bit(BIT_WIDE_LINE); }
+
+    /** Whether vertex color replaces material ambient in this variant. */
+    public boolean cmReplacesAmbient()    { final int m = colorMaterialMode(); return m == CM_AMBIENT || m == CM_AMBIENT_AND_DIFFUSE; }
+    /** Whether vertex color replaces material diffuse in this variant. */
+    public boolean cmReplacesDiffuse()    { final int m = colorMaterialMode(); return m == CM_DIFFUSE || m == CM_AMBIENT_AND_DIFFUSE; }
+    /** Whether vertex color replaces material specular in this variant. */
+    public boolean cmReplacesSpecular()   { return colorMaterialMode() == CM_SPECULAR; }
+    /** Whether vertex color replaces material emission in this variant. */
+    public boolean cmReplacesEmission()   { return colorMaterialMode() == CM_EMISSION; }
+
+    private boolean bit(int pos) { return ((packed >> pos) & 1) != 0; }
+
+    static int encodeTexGenMode(int glMode) {
+        return switch (glMode) {
+            case GL11.GL_OBJECT_LINEAR -> TG_OBJ_LINEAR;
+            case GL11.GL_EYE_LINEAR -> TG_EYE_LINEAR;
+            default -> TG_NONE;
+        };
+    }
+
+    static int encodeColorMaterialMode(int glMode) {
+        return switch (glMode) {
+            case GL11.GL_AMBIENT -> CM_AMBIENT;
+            case GL11.GL_DIFFUSE -> CM_DIFFUSE;
+            case GL11.GL_SPECULAR -> CM_SPECULAR;
+            case GL11.GL_EMISSION -> CM_EMISSION;
+            case GL11.GL_AMBIENT_AND_DIFFUSE -> CM_AMBIENT_AND_DIFFUSE;
+            default -> CM_AMBIENT_AND_DIFFUSE;
+        };
+    }
+
+    public static long packFromState(boolean hasColor, boolean hasNormal, boolean hasTexCoord, boolean hasLightmap) {
+        long bits = 0;
+
+        final boolean lighting = GLStateManager.getLightingState().isEnabled();
+        if (lighting) {
+            bits |= (1L << BIT_LIGHTING);
+
+            if (GLStateManager.getLightStates()[0].isEnabled()) {
+                bits |= (1L << BIT_LIGHT0);
+                // position.w == 0 means directional
+                if (GLStateManager.getLightDataStates()[0].position.w == 0.0f) {
+                    bits |= (1L << BIT_LIGHT0_DIR);
+                }
+            }
+            if (GLStateManager.getLightStates()[1].isEnabled()) {
+                bits |= (1L << BIT_LIGHT1);
+                if (GLStateManager.getLightDataStates()[1].position.w == 0.0f) {
+                    bits |= (1L << BIT_LIGHT1_DIR);
+                }
+            }
+
+            if (GLStateManager.getColorMaterial().isEnabled()) {
+                bits |= (1L << BIT_COLOR_MATERIAL);
+                final int cmMode = encodeColorMaterialMode(GLStateManager.getColorMaterialParameter().getValue());
+                bits |= ((long) cmMode & 0x7) << BIT_COLOR_MAT_MODE;
+            }
+
+            if (GLStateManager.getLightModel().colorControl == GL12.GL_SEPARATE_SPECULAR_COLOR) {
+                bits |= (1L << BIT_SEPARATE_SPECULAR);
+            }
+        }
+
+        if (GLStateManager.getFogMode().isEnabled()) {
+            bits |= (1L << BIT_FOG);
+            final int fogDistMode = GLStateManager.getFogState().getFogDistanceMode();
+            bits |= ((long) fogDistMode & 0x3) << BIT_FOG_DIST_MODE;
+        }
+
+        if (GLStateManager.getNormalizeState().isEnabled()) {
+            bits |= (1L << BIT_NORMALIZE);
+        }
+        if (GLStateManager.getRescaleNormalState().isEnabled()) {
+            bits |= (1L << BIT_RESCALE_NORMAL);
+        }
+
+        // Texture unit 0 (base texture)
+        if (GLStateManager.getTextures().getTextureUnitStates(0).isEnabled()) {
+            bits |= (1L << BIT_TEXTURE);
+        }
+        // Texture unit 1 (lightmap)
+        if (GLStateManager.getTextures().getTextureUnitStates(1).isEnabled()) {
+            bits |= (1L << BIT_LIGHTMAP);
+        }
+
+        // Check if texture matrix unit 0 is non-identity
+        final Matrix4f texMat = GLStateManager.getTextures().getTextureUnitMatrix(0);
+        if (!DisplayListManager.isIdentity(texMat)) {
+            bits |= (1L << BIT_TEX_MATRIX);
+        }
+
+        // TexGen (unit 0 only) — encode per-coordinate mode if enabled
+        final var texUnit = GLStateManager.getTextures();
+        final TexGenState tg = texUnit.getTexGenState(0);
+        boolean anyTexGen = false;
+        if (texUnit.getTexGenSStates(0).isEnabled() && tg.getMode(GL11.GL_S) != 0) {
+            final int m = encodeTexGenMode(tg.getMode(GL11.GL_S));
+            bits |= ((long) m & 0x7) << BIT_TEXGEN_S;
+            if (m != TG_NONE) anyTexGen = true;
+        }
+        if (texUnit.getTexGenTStates(0).isEnabled() && tg.getMode(GL11.GL_T) != 0) {
+            final int m = encodeTexGenMode(tg.getMode(GL11.GL_T));
+            bits |= ((long) m & 0x7) << BIT_TEXGEN_T;
+            if (m != TG_NONE) anyTexGen = true;
+        }
+        if (texUnit.getTexGenRStates(0).isEnabled() && tg.getMode(GL11.GL_R) != 0) {
+            final int m = encodeTexGenMode(tg.getMode(GL11.GL_R));
+            bits |= ((long) m & 0x7) << BIT_TEXGEN_R;
+            if (m != TG_NONE) anyTexGen = true;
+        }
+        if (texUnit.getTexGenQStates(0).isEnabled() && tg.getMode(GL11.GL_Q) != 0) {
+            final int m = encodeTexGenMode(tg.getMode(GL11.GL_Q));
+            bits |= ((long) m & 0x7) << BIT_TEXGEN_Q;
+            if (m != TG_NONE) anyTexGen = true;
+        }
+        // Force texture matrix on when texgen is active (end portal pattern always uses it)
+        if (anyTexGen) {
+            bits |= (1L << BIT_TEX_MATRIX);
+        }
+
+        // Vertex format flags
+        if (hasColor) bits |= (1L << BIT_HAS_VERTEX_COLOR);
+        if (hasNormal) bits |= (1L << BIT_HAS_VERTEX_NORMAL);
+        if (hasTexCoord) bits |= (1L << BIT_HAS_VERTEX_TEX);
+        if (hasLightmap) bits |= (1L << BIT_HAS_VERTEX_LIGHTMAP);
+
+        // Clip planes
+        if (GLStateManager.anyClipPlaneEnabled()) {
+            bits |= (1L << BIT_CLIP_PLANES);
+        }
+
+        // Wide line GS emulation
+        if (GLStateManager.wideLineEmulationActive) {
+            bits |= (1L << BIT_WIDE_LINE);
+        }
+
+        return bits;
+    }
+
+    public static VertexKey fromState(boolean hasColor, boolean hasNormal, boolean hasTexCoord, boolean hasLightmap) {
+        return new VertexKey(packFromState(hasColor, hasNormal, hasTexCoord, hasLightmap));
+    }
+
+    static VertexKey fromPacked(long packed) {
+        return new VertexKey(packed);
+    }
+
+    @Override
+    public int hashCode() {
+        return Long.hashCode(packed);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (!(obj instanceof VertexKey other)) return false;
+        return packed == other.packed;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("FFPVertexKey[0x%09X: lit=%b l0=%b l1=%b cm=%b fog=%b tex=%b lm=%b col=%b nrm=%b vtex=%b vlm=%b tg=%d/%d/%d/%d clip=%b wline=%b]",
+            packed, lightingEnabled(), light0Enabled(), light1Enabled(),
+            colorMaterialEnabled(), fogEnabled(), textureEnabled(), lightmapEnabled(),
+            hasVertexColor(), hasVertexNormal(), hasVertexTexCoord(), hasVertexLightmap(),
+            texGenModeS(), texGenModeT(), texGenModeR(), texGenModeQ(), clipPlanesEnabled(), wideLineEmulation());
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/ffp/VertexShaderGenerator.java

@@ -0,0 +1,416 @@
+package com.gtnewhorizons.angelica.glsm.ffp;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormatElement;
+
+/**
+ * Generates GLSL 330 core vertex shaders for FFP emulation.
+ * Follows Mesa's ffvertex_prog.c build order.
+ *
+ * Attribute locations are sourced from {@link VertexFormatElement.Usage} to stay in sync with GTNHLib's vertex format setup.
+ */
+public final class VertexShaderGenerator {
+
+    private VertexShaderGenerator() {}
+
+    public static String generate(VertexKey key) {
+        final StringBuilder sb = new StringBuilder(2048);
+        sb.append("#version 330 core\n\n");
+
+        emitAttributes(sb, key);
+        emitUniforms(sb, key);
+        emitOutputs(sb, key);
+
+        sb.append("void main() {\n");
+        emitPositionTransform(sb, key);
+        if (key.lightingEnabled()) {
+            emitNormalTransform(sb, key);
+            emitLighting(sb, key);
+        } else {
+            emitColorPassthrough(sb, key);
+        }
+        emitTexCoordPassthrough(sb, key);
+        if (key.fogEnabled()) {
+            emitFogDistance(sb, key);
+        }
+        if (key.clipPlanesEnabled()) {
+            emitClipDistances(sb);
+        }
+        sb.append("}\n");
+
+        String source = sb.toString();
+        if (key.wideLineEmulation()) {
+            source = source.replace("v_SpecularColor", "v_SpecularColor_gs")
+                           .replace("v_TexCoord0", "v_TexCoord0_gs")
+                           .replace("v_TexCoord1", "v_TexCoord1_gs")
+                           .replace("v_FogCoord", "v_FogCoord_gs")
+                           .replace("v_Color", "v_Color_gs");
+        }
+        return source;
+    }
+
+    private static void emitAttributes(StringBuilder sb, VertexKey key) {
+        sb.append("// Vertex attributes\n");
+        sb.append("layout(location = ").append(VertexFormatElement.Usage.POSITION.getAttributeLocation()).append(") in vec3 a_Position;\n");
+        if (key.hasVertexColor()) {
+            sb.append("layout(location = ").append(VertexFormatElement.Usage.COLOR.getAttributeLocation()).append(") in vec4 a_Color;\n");
+        }
+        if (key.hasVertexTexCoord()) {
+            sb.append("layout(location = ").append(VertexFormatElement.Usage.PRIMARY_UV.getAttributeLocation()).append(") in vec2 a_TexCoord0;\n");
+        }
+        if (key.hasVertexLightmap()) {
+            sb.append("layout(location = ").append(VertexFormatElement.Usage.SECONDARY_UV.getAttributeLocation()).append(") in vec2 a_TexCoord1;\n");
+        }
+        if (key.hasVertexNormal()) {
+            sb.append("layout(location = ").append(VertexFormatElement.Usage.NORMAL.getAttributeLocation()).append(") in vec3 a_Normal;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitUniforms(StringBuilder sb, VertexKey key) {
+        sb.append("// Matrices\n");
+        sb.append("uniform mat4 u_ModelViewMatrix;\n");
+        sb.append("uniform mat4 u_ProjectionMatrix;\n");
+        sb.append("uniform mat4 u_MVPMatrix;\n");
+
+        if (key.lightingEnabled()) {
+            sb.append("uniform mat3 u_NormalMatrix;\n");
+        }
+
+        if (key.textureMatrixEnabled()) {
+            sb.append("uniform mat4 u_TextureMatrix0;\n");
+        }
+
+        // TexGen plane uniforms
+        if (key.texGenModeS() == VertexKey.TG_OBJ_LINEAR) sb.append("uniform vec4 u_TexGenObjPlaneS;\n");
+        if (key.texGenModeS() == VertexKey.TG_EYE_LINEAR) sb.append("uniform vec4 u_TexGenEyePlaneS;\n");
+        if (key.texGenModeT() == VertexKey.TG_OBJ_LINEAR) sb.append("uniform vec4 u_TexGenObjPlaneT;\n");
+        if (key.texGenModeT() == VertexKey.TG_EYE_LINEAR) sb.append("uniform vec4 u_TexGenEyePlaneT;\n");
+        if (key.texGenModeR() == VertexKey.TG_OBJ_LINEAR) sb.append("uniform vec4 u_TexGenObjPlaneR;\n");
+        if (key.texGenModeR() == VertexKey.TG_EYE_LINEAR) sb.append("uniform vec4 u_TexGenEyePlaneR;\n");
+        if (key.texGenModeQ() == VertexKey.TG_OBJ_LINEAR) sb.append("uniform vec4 u_TexGenObjPlaneQ;\n");
+        if (key.texGenModeQ() == VertexKey.TG_EYE_LINEAR) sb.append("uniform vec4 u_TexGenEyePlaneQ;\n");
+
+        if (!key.hasVertexNormal() && key.lightingEnabled()) {
+            sb.append("uniform vec3 u_CurrentNormal;\n");
+        }
+
+        if (!key.hasVertexColor()) {
+            sb.append("uniform vec4 u_CurrentColor;\n");
+        }
+
+        if (!key.hasVertexTexCoord() && key.textureEnabled()) {
+            sb.append("uniform vec4 u_CurrentTexCoord;\n");
+        }
+
+        if (key.lightmapEnabled() && !key.hasVertexLightmap()) {
+            sb.append("uniform vec2 u_CurrentLightmapCoord;\n");
+        }
+
+        if (key.lightmapEnabled()) {
+            sb.append("uniform mat4 u_LightmapTextureMatrix;\n");
+        }
+
+        if (key.lightingEnabled()) {
+            emitLightingUniforms(sb, key);
+        }
+
+        if (key.lightingEnabled() && (key.normalizeEnabled() || key.rescaleNormalsEnabled())) {
+            // normalize is done in shader; rescale uses normalScale
+            if (key.rescaleNormalsEnabled() && !key.normalizeEnabled()) {
+                sb.append("uniform float u_NormalScale;\n");
+            }
+        }
+
+        if (key.clipPlanesEnabled()) {
+            sb.append("uniform vec4 u_ClipPlane[8];\n");
+        }
+
+        sb.append('\n');
+    }
+
+    private static void emitLightingUniforms(StringBuilder sb, VertexKey key) {
+        sb.append("\n// Lighting\n");
+
+        if (key.colorMaterialEnabled()) {
+            // When color material is active, we can't pre-compute light products so we upload raw light and material values
+            sb.append("uniform vec4 u_LightModelAmbient;\n");
+            sb.append("uniform vec4 u_MaterialEmission;\n");
+            sb.append("uniform vec4 u_MaterialAmbient;\n");
+            sb.append("uniform vec4 u_MaterialDiffuse;\n");
+            sb.append("uniform vec4 u_MaterialSpecular;\n");
+            sb.append("uniform float u_MaterialShininess;\n");
+
+            if (key.light0Enabled()) {
+                sb.append("uniform vec4 u_Light0Ambient;\n");
+                sb.append("uniform vec4 u_Light0Diffuse;\n");
+                sb.append("uniform vec4 u_Light0Specular;\n");
+                sb.append("uniform vec4 u_Light0Position;\n");
+            }
+            if (key.light1Enabled()) {
+                sb.append("uniform vec4 u_Light1Ambient;\n");
+                sb.append("uniform vec4 u_Light1Diffuse;\n");
+                sb.append("uniform vec4 u_Light1Specular;\n");
+                sb.append("uniform vec4 u_Light1Position;\n");
+            }
+        } else {
+            // Pre-computed: sceneColor + lightProducts
+            sb.append("uniform vec4 u_SceneColor;\n");
+
+            if (key.light0Enabled()) {
+                sb.append("uniform vec4 u_Light0Position;\n");
+                sb.append("uniform vec3 u_LightProd0Ambient;\n");
+                sb.append("uniform vec3 u_LightProd0Diffuse;\n");
+                sb.append("uniform vec3 u_LightProd0Specular;\n");
+            }
+            if (key.light1Enabled()) {
+                sb.append("uniform vec4 u_Light1Position;\n");
+                sb.append("uniform vec3 u_LightProd1Ambient;\n");
+                sb.append("uniform vec3 u_LightProd1Diffuse;\n");
+                sb.append("uniform vec3 u_LightProd1Specular;\n");
+            }
+            sb.append("uniform float u_MaterialShininess;\n");
+        }
+    }
+
+    private static void emitOutputs(StringBuilder sb, VertexKey key) {
+        sb.append("// Outputs\n");
+        sb.append("out vec4 v_Color;\n");
+        if (key.separateSpecular()) {
+            sb.append("out vec3 v_SpecularColor;\n");
+        }
+        if (key.textureEnabled() || key.hasVertexTexCoord() || key.texGenEnabled()) {
+            sb.append("out vec4 v_TexCoord0;\n");
+        }
+        if (key.lightmapEnabled()) {
+            sb.append("out vec4 v_TexCoord1;\n");
+        }
+        if (key.fogEnabled()) {
+            sb.append("out float v_FogCoord;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitPositionTransform(StringBuilder sb, VertexKey key) {
+        sb.append("  // Position transform\n");
+        sb.append("  vec4 pos4 = vec4(a_Position, 1.0);\n");
+        sb.append("  gl_Position = u_MVPMatrix * pos4;\n");
+
+        // Eye position needed for lighting, fog, EYE_LINEAR texgen, and clip planes
+        if (key.lightingEnabled() || key.fogEnabled() || texGenNeedsEyePos(key) || key.clipPlanesEnabled()) {
+            sb.append("  vec4 eyePos = u_ModelViewMatrix * pos4;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitNormalTransform(StringBuilder sb, VertexKey key) {
+        sb.append("  // Normal transform\n");
+        if (key.hasVertexNormal()) {
+            sb.append("  vec3 normal = u_NormalMatrix * a_Normal;\n");
+        } else {
+            sb.append("  vec3 normal = u_NormalMatrix * u_CurrentNormal;\n");
+        }
+
+        if (key.normalizeEnabled()) {
+            sb.append("  normal = normalize(normal);\n");
+        } else if (key.rescaleNormalsEnabled()) {
+            sb.append("  normal *= u_NormalScale;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitLighting(StringBuilder sb, VertexKey key) {
+        sb.append("  // Gouraud lighting\n");
+
+        if (key.colorMaterialEnabled()) {
+            // Color material: vertex color replaces specific material properties per glColorMaterial mode (Mesa ffvertex_prog.c get_material() bitmask approach)
+            sb.append("  vec4 matColor = ");
+            sb.append(key.hasVertexColor() ? "a_Color" : "u_CurrentColor");
+            sb.append(";\n");
+
+            // Emission source: vertex color for CM_EMISSION, else material uniform
+            final String emSrc = key.cmReplacesEmission() ? "matColor.rgb" : "u_MaterialEmission.rgb";
+            // Ambient source for scene color: vertex color for CM_AMBIENT / CM_AMBIENT_AND_DIFFUSE
+            final String amSrc = key.cmReplacesAmbient() ? "matColor.rgb" : "u_MaterialAmbient.rgb";
+            sb.append("  vec3 sceneColor = ").append(emSrc).append(" + ").append(amSrc).append(" * u_LightModelAmbient.rgb;\n");
+
+            // Alpha from diffuse source (per GL spec)
+            sb.append("  float outAlpha = ").append(key.cmReplacesDiffuse() ? "matColor.a" : "u_MaterialDiffuse.a").append(";\n");
+        } else {
+            // Pre-computed scene color
+            sb.append("  vec3 sceneColor = u_SceneColor.rgb;\n");
+            sb.append("  float outAlpha = u_SceneColor.a;\n");
+        }
+
+        sb.append("  vec3 color0 = sceneColor;\n");
+        if (key.separateSpecular()) {
+            sb.append("  vec3 specAccum = vec3(0.0);\n");
+        }
+
+        // Per-light accumulation
+        if (key.light0Enabled()) {
+            emitLightContribution(sb, key, 0);
+        }
+        if (key.light1Enabled()) {
+            emitLightContribution(sb, key, 1);
+        }
+
+        sb.append("  v_Color = vec4(clamp(color0, 0.0, 1.0), outAlpha);\n");
+        if (key.separateSpecular()) {
+            sb.append("  v_SpecularColor = clamp(specAccum, 0.0, 1.0);\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitLightContribution(StringBuilder sb, VertexKey key, int lightIndex) {
+        final String li = String.valueOf(lightIndex);
+        final boolean directional = (lightIndex == 0) ? key.light0Directional() : key.light1Directional();
+        final String posUniform = "u_Light" + li + "Position";
+
+        sb.append("  { // Light ").append(li).append('\n');
+
+        // Light vector
+        if (directional) {
+            // Directional: position is already normalized direction
+            sb.append("    vec3 VPpli = normalize(").append(posUniform).append(".xyz);\n");
+        } else {
+            // Positional light
+            sb.append("    vec3 VPpli = ").append(posUniform).append(".xyz - eyePos.xyz;\n");
+            sb.append("    VPpli = normalize(VPpli);\n");
+        }
+
+        // Dot products
+        sb.append("    float NdotVP = max(dot(normal, VPpli), 0.0);\n");
+
+        // Half vector for specular (infinite viewer: H = normalize(L + (0,0,1)))
+        sb.append("    vec3 halfVec = normalize(VPpli + vec3(0.0, 0.0, 1.0));\n");
+        sb.append("    float NdotHV = max(dot(normal, halfVec), 0.0);\n");
+
+        // Specular power
+        sb.append("    float spec = (NdotVP > 0.0 && u_MaterialShininess > 0.0) ? pow(NdotHV, u_MaterialShininess) : 0.0;\n");
+
+        // Accumulate — per-property source depends on color material mode
+        if (key.colorMaterialEnabled()) {
+            final String ambU = "u_Light" + li + "Ambient";
+            final String difU = "u_Light" + li + "Diffuse";
+            final String speU = "u_Light" + li + "Specular";
+            // Ambient product: light.ambient * (vertex color or material)
+            final String ambMat = key.cmReplacesAmbient() ? "matColor.rgb" : "u_MaterialAmbient.rgb";
+            sb.append("    vec3 ambient = ").append(ambU).append(".rgb * ").append(ambMat).append(";\n");
+            // Diffuse product
+            final String difMat = key.cmReplacesDiffuse() ? "matColor.rgb" : "u_MaterialDiffuse.rgb";
+            sb.append("    vec3 diffuse = ").append(difU).append(".rgb * ").append(difMat).append(";\n");
+            // Specular product
+            final String speMat = key.cmReplacesSpecular() ? "matColor.rgb" : "u_MaterialSpecular.rgb";
+            sb.append("    vec3 specular = ").append(speU).append(".rgb * ").append(speMat).append(";\n");
+        } else {
+            sb.append("    vec3 ambient = u_LightProd").append(li).append("Ambient;\n");
+            sb.append("    vec3 diffuse = u_LightProd").append(li).append("Diffuse;\n");
+            sb.append("    vec3 specular = u_LightProd").append(li).append("Specular;\n");
+        }
+
+        sb.append("    color0 += ambient + NdotVP * diffuse;\n");
+        if (key.separateSpecular()) {
+            sb.append("    specAccum += spec * specular;\n");
+        } else {
+            sb.append("    color0 += spec * specular;\n");
+        }
+
+        sb.append("  }\n");
+    }
+
+    private static void emitColorPassthrough(StringBuilder sb, VertexKey key) {
+        sb.append("  // Color passthrough (no lighting)\n");
+        if (key.hasVertexColor()) {
+            sb.append("  v_Color = a_Color;\n");
+        } else {
+            sb.append("  v_Color = u_CurrentColor;\n");
+        }
+        sb.append('\n');
+    }
+
+    private static void emitTexCoordPassthrough(StringBuilder sb, VertexKey key) {
+        if (key.texGenEnabled()) {
+            emitTexGenCoordGeneration(sb, key);
+        } else if (key.textureEnabled() || key.hasVertexTexCoord()) {
+            sb.append("  // Texture coordinates\n");
+            if (key.hasVertexTexCoord()) {
+                if (key.textureMatrixEnabled()) {
+                    sb.append("  v_TexCoord0 = u_TextureMatrix0 * vec4(a_TexCoord0, 0.0, 1.0);\n");
+                } else {
+                    sb.append("  v_TexCoord0 = vec4(a_TexCoord0, 0.0, 1.0);\n");
+                }
+            } else {
+                if (key.textureMatrixEnabled()) {
+                    sb.append("  v_TexCoord0 = u_TextureMatrix0 * u_CurrentTexCoord;\n");
+                } else {
+                    sb.append("  v_TexCoord0 = u_CurrentTexCoord;\n");
+                }
+            }
+        }
+        if (key.lightmapEnabled()) {
+            if (key.hasVertexLightmap()) {
+                sb.append("  v_TexCoord1 = u_LightmapTextureMatrix * vec4(a_TexCoord1, 0.0, 1.0);\n");
+            } else {
+                sb.append("  v_TexCoord1 = u_LightmapTextureMatrix * vec4(u_CurrentLightmapCoord, 0.0, 1.0);\n");
+            }
+        }
+    }
+
+    /**
+     * Emit per-coordinate texgen code following Mesa's ffvertex_prog.c build order.
+     * OBJ_LINEAR: dot(pos4, objPlane), EYE_LINEAR: dot(eyePos, eyePlane).
+     * Coordinates without texgen use vertex attrib or default (0,0,0,1).
+     */
+    private static void emitTexGenCoordGeneration(StringBuilder sb, VertexKey key) {
+        sb.append("  // TexGen coordinate generation\n");
+        sb.append("  vec4 texGenCoord = vec4(0.0, 0.0, 0.0, 1.0);\n");
+
+        emitTexGenComponent(sb, key.texGenModeS(), "s", "S", key);
+        emitTexGenComponent(sb, key.texGenModeT(), "t", "T", key);
+        emitTexGenComponent(sb, key.texGenModeR(), "r", "R", key);
+        emitTexGenComponent(sb, key.texGenModeQ(), "q", "Q", key);
+
+        // Always apply texture matrix when texgen is active (forced on in VertexKey)
+        sb.append("  v_TexCoord0 = u_TextureMatrix0 * texGenCoord;\n");
+    }
+
+    private static void emitTexGenComponent(StringBuilder sb, int mode, String swizzle, String coordName, VertexKey key) {
+        switch (mode) {
+            case VertexKey.TG_OBJ_LINEAR ->
+                sb.append("  texGenCoord.").append(swizzle).append(" = dot(pos4, u_TexGenObjPlane").append(coordName).append(");\n");
+            case VertexKey.TG_EYE_LINEAR ->
+                sb.append("  texGenCoord.").append(swizzle).append(" = dot(eyePos, u_TexGenEyePlane").append(coordName).append(");\n");
+            // TG_NONE: keep default (0 for s/t/r, 1 for q) — already set in texGenCoord init
+        }
+    }
+
+    private static boolean texGenNeedsEyePos(VertexKey key) {
+        return key.texGenModeS() == VertexKey.TG_EYE_LINEAR
+            || key.texGenModeT() == VertexKey.TG_EYE_LINEAR
+            || key.texGenModeR() == VertexKey.TG_EYE_LINEAR
+            || key.texGenModeQ() == VertexKey.TG_EYE_LINEAR;
+    }
+
+    private static void emitFogDistance(StringBuilder sb, VertexKey key) {
+        sb.append("  // Fog distance\n");
+        // Mesa ffvertex_prog.c build_fog(): FDM_EYE_RADIAL/EYE_PLANE/EYE_PLANE_ABS
+        final int fogDistMode = key.fogDistanceMode();
+        switch (fogDistMode) {
+            case 0 -> // FDM_EYE_RADIAL: Euclidean distance
+                sb.append("  v_FogCoord = length(eyePos.xyz);\n");
+            case 1 -> // FDM_EYE_PLANE: raw Z (can be negative, clamped by fog factor)
+                sb.append("  v_FogCoord = eyePos.z;\n");
+            case 2 -> // FDM_EYE_PLANE_ABS: absolute Z
+                sb.append("  v_FogCoord = abs(eyePos.z);\n");
+            default ->
+                sb.append("  v_FogCoord = abs(eyePos.z);\n");
+        }
+    }
+
+    private static void emitClipDistances(StringBuilder sb) {
+        sb.append("  // Clip distances\n");
+        for (int i = 0; i < 8; i++) {
+            sb.append("  gl_ClipDistance[").append(i).append("] = dot(u_ClipPlane[").append(i).append("], eyePos);\n");
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/AccumulatedDraw.java

@@ -1,11 +1,10 @@
 package com.gtnewhorizons.angelica.glsm.recording;
 
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.quad.ModelQuadViewMutable;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.util.ModelQuadUtil;
-import org.joml.Matrix4f;
+import com.gtnewhorizon.gtnhlib.client.renderer.DirectTessellator;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
 
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
 import java.util.List;
 
 /**
@@ -13,54 +12,53 @@ import java.util.List;
  * Matrix-as-Data Architecture: Stores untransformed vertices + captured matrix.
  * The matrix will be applied at runtime, not baked into vertices.
  */
-public class AccumulatedDraw {
-    public final List<ModelQuadViewMutable> quads;
-    public final Matrix4f transform;
-    public final CapturingTessellator.Flags flags;
+public final class AccumulatedDraw {
+    public final VertexFormat format;
+    public final List<ByteBuffer> drawBuffers;
+    public final int drawMode;
     public final int commandIndex; // Position in command list for state tracking
-    public final int matrixGeneration; // For batching: same generation = same transform context
-    public final int stateGeneration; // Same value = no state commands between draws, can merge
+    public final int stateGeneration; // Position in command list for state tracking
+    public RestoreData restoreData;
 
-    /**
-     * Last vertex restoration data for immediate mode draws.
-     * Null for tessellator draws (no restoration needed).
-     */
-    public final RestoreData restoreData;
+    public AccumulatedDraw(DirectTessellator tessellator, int commandIndex, int stateGeneration, boolean copyLast) {
+        this.format = tessellator.getVertexFormat();
+        this.drawMode = tessellator.drawMode;
+        this.drawBuffers = new ArrayList<>();
+        this.drawBuffers.add(tessellator.allocateBufferCopy());
+        this.commandIndex = commandIndex;
+        this.stateGeneration = stateGeneration;
+
+        if (copyLast) {
+            this.restoreData = new RestoreData(tessellator);
+        }
+    }
+
+
+    public void mergeDraw(DirectTessellator tessellator, boolean copyLast) {
+        this.drawBuffers.add(tessellator.allocateBufferCopy());
+
+        if (copyLast) {
+            this.restoreData = new RestoreData(tessellator);
+        }
+    }
 
     /**
      * Holds last vertex attribute values for GL state restoration after VBO draw.
      * Used to sync GLSM cache with actual GL state after VBO rendering.
      */
-    @Desugar
-    public record RestoreData(
-        float lastColorR, float lastColorG, float lastColorB, float lastColorA,
-        float lastNormalX, float lastNormalY, float lastNormalZ,
-        float lastTexCoordS, float lastTexCoordT) {}
+    public static final class RestoreData {
+        public final int lastColor;
+        public final int lastNormal;
+        public final float lastTexCoordU;
+        public final float lastTexCoordV;
+        public final int flags;
 
-    public AccumulatedDraw(List<ModelQuadViewMutable> quads, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int matrixGeneration) {
-        this(quads, transform, flags, commandIndex, matrixGeneration, 0, null);
-    }
-
-    public AccumulatedDraw(List<ModelQuadViewMutable> quads, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int matrixGeneration, int stateGeneration) {
-        this(quads, transform, flags, commandIndex, matrixGeneration, stateGeneration, null);
-    }
-
-    public AccumulatedDraw(List<ModelQuadViewMutable> quads, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int matrixGeneration, int stateGeneration, RestoreData restoreData) {
-        // Deep copy quads - pooled quads are reused after callback
-        this.quads = ModelQuadUtil.deepCopyQuads(quads);
-
-        this.transform = new Matrix4f(transform); // Snapshot for runtime application
-        this.flags = flags;
-        this.commandIndex = commandIndex;
-        this.matrixGeneration = matrixGeneration;
-        this.stateGeneration = stateGeneration;
-        this.restoreData = restoreData;
-    }
-
-    @Override
-    public String toString() {
-        return String.format("AccumulatedDraw[quads=%d, cmdIdx=%d, matrixGen=%d, stateGen=%d, flags=C%dT%dL%dN%d, restore=%s]",
-            quads.size(), commandIndex, matrixGeneration, stateGeneration, flags.hasColor ? 1 : 0, flags.hasTexture ? 1 : 0, flags.hasBrightness ? 1 : 0, flags.hasNormals ? 1 : 0,
-            restoreData != null ? "yes" : "no");
+        public RestoreData(DirectTessellator tessellator) {
+            this.lastColor = tessellator.getPackedColor();
+            this.lastNormal = tessellator.getPackedNormal();
+            this.lastTexCoordU = (float) tessellator.getLastTextureU();
+            this.lastTexCoordV = (float) tessellator.getLastTextureV();
+            this.flags = tessellator.getVertexFormat().getVertexFlags();
+        }
     }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/recording/AccumulatedLineDraw.java

@@ -1,39 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.recording;
-
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import org.joml.Matrix4f;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Represents an accumulated line draw call during display list compilation.
- * Similar to AccumulatedDraw but for line primitives.
- * Stores untransformed line vertices + captured matrix.
- */
-public class AccumulatedLineDraw {
-    public final List<ImmediateModeRecorder.LineVertex> lines;
-    public final Matrix4f transform;
-    public final CapturingTessellator.Flags flags;
-    public final int commandIndex; // Position in command list for state tracking
-    public final int stateGeneration; // Same value = no state commands between draws, can merge
-
-    public AccumulatedLineDraw(List<ImmediateModeRecorder.LineVertex> lines, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex) {
-        this(lines, transform, flags, commandIndex, 0);
-    }
-
-    public AccumulatedLineDraw(List<ImmediateModeRecorder.LineVertex> lines, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int stateGeneration) {
-        // Copy lines - the source list may be cleared
-        this.lines = new ArrayList<>(lines);
-        this.transform = new Matrix4f(transform); // Snapshot for runtime application
-        this.flags = flags;
-        this.commandIndex = commandIndex;
-        this.stateGeneration = stateGeneration;
-    }
-
-    @Override
-    public String toString() {
-        return String.format("AccumulatedLineDraw[lines=%d, cmdIdx=%d, flags=C%dT%dL%dN%d]",
-            lines.size() / 2, commandIndex, flags.hasColor ? 1 : 0, flags.hasTexture ? 1 : 0, flags.hasBrightness ? 1 : 0, flags.hasNormals ? 1 : 0);
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/AccumulatedPrimitiveDraw.java

@@ -1,66 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.recording;
-
-import com.gtnewhorizon.gtnhlib.client.renderer.CapturingTessellator;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.line.ModelLine;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.primitive.ModelPrimitiveView;
-import com.gtnewhorizon.gtnhlib.client.renderer.cel.model.tri.ModelTriangle;
-import org.joml.Matrix4f;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Represents an accumulated primitive draw call during display list compilation.
- * Stores primitives (lines, triangles) from tessellator callback with their transform.
- * <p>
- * Unlike AccumulatedLineDraw which stores ImmediateModeRecorder.LineVertex (16-byte: pos+color),
- * this stores ModelPrimitiveView (32-byte: pos+color+tex+light+normal) from the tessellator.
- */
-public class AccumulatedPrimitiveDraw {
-    public final List<ModelPrimitiveView> primitives;
-    public final Matrix4f transform;
-    public final CapturingTessellator.Flags flags;
-    public final int commandIndex;
-    public final int matrixGeneration; // For batching: same generation = same transform context
-    public final int stateGeneration; // Same value = no state commands between draws, can merge
-
-    public AccumulatedPrimitiveDraw(List<ModelPrimitiveView> primitives, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int matrixGeneration) {
-        this(primitives, transform, flags, commandIndex, matrixGeneration, 0);
-    }
-
-    public AccumulatedPrimitiveDraw(List<ModelPrimitiveView> primitives, Matrix4f transform, CapturingTessellator.Flags flags, int commandIndex, int matrixGeneration, int stateGeneration) {
-        // Deep copy primitives - pooled primitives are reused after callback
-        this.primitives = deepCopyPrimitives(primitives);
-        this.transform = new Matrix4f(transform);
-        this.flags = flags;
-        this.commandIndex = commandIndex;
-        this.matrixGeneration = matrixGeneration;
-        this.stateGeneration = stateGeneration;
-    }
-
-    /**
-     * Creates deep copies of all primitives in the list.
-     * Required because CapturingTessellator pools and reuses primitive objects.
-     */
-    private static List<ModelPrimitiveView> deepCopyPrimitives(List<ModelPrimitiveView> source) {
-        final int size = source.size();
-        final List<ModelPrimitiveView> copies = new ArrayList<>(size);
-        for (int i = 0; i < size; i++) {
-            final ModelPrimitiveView prim = source.get(i);
-            if (prim instanceof ModelLine ml) {
-                copies.add(new ModelLine().copyFrom(ml));
-            } else if (prim instanceof ModelTriangle mt) {
-                copies.add(new ModelTriangle().copyFrom(mt));
-            }
-        }
-        return copies;
-    }
-
-    @Override
-    public String toString() {
-        return String.format("AccumulatedPrimitiveDraw[primitives=%d, cmdIdx=%d, matrixGen=%d, stateGen=%d, mode=%d, flags=C%dT%dL%dN%d]",
-            primitives.size(), commandIndex, matrixGeneration, stateGeneration, flags.drawMode,
-            flags.hasColor ? 1 : 0, flags.hasTexture ? 1 : 0,
-            flags.hasBrightness ? 1 : 0, flags.hasNormals ? 1 : 0);
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/CommandBuffer.java

@@ -14,12 +14,6 @@ import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.*;
 public final class CommandBuffer {
     private static final int DEFAULT_CAPACITY = 4096; // Guess at typical display list size
 
-    // Flag bits for DRAW_RANGE_RESTORE command
-    public static final int FLAG_HAS_BRIGHTNESS = 1 << 0;
-    public static final int FLAG_HAS_COLOR      = 1 << 1;
-    public static final int FLAG_HAS_NORMALS    = 1 << 2;
-    public static final int FLAG_HAS_TEXTURE    = 1 << 3;
-
     private ByteBuffer buffer;
     private long basePointer;
     private long writePointer;
@@ -42,6 +36,11 @@ public final class CommandBuffer {
         writePointer += 4;
     }
 
+    private void writeLong(long value) {
+        memPutLong(writePointer, value);
+        writePointer += 8;
+    }
+
     private void writeFloat(float value) {
         memPutFloat(writePointer, value);
         writePointer += 4;
@@ -264,6 +263,15 @@ public final class CommandBuffer {
         writeInt(height);
     }
 
+    public void writeScissor(int x, int y, int width, int height) {
+        ensureCapacity(20);
+        writeInt(GLCommand.SCISSOR);
+        writeInt(x);
+        writeInt(y);
+        writeInt(width);
+        writeInt(height);
+    }
+
     public void writeBlendFunc(int srcRgb, int dstRgb, int srcAlpha, int dstAlpha) {
         ensureCapacity(20);
         writeInt(GLCommand.BLEND_FUNC);
@@ -546,15 +554,22 @@ public final class CommandBuffer {
         }
     }
 
+    public void writeClipPlane(int plane, double a, double b, double c, double d) {
+        ensureCapacity(40);
+        writeInt(GLCommand.CLIP_PLANE);
+        writeInt(plane);
+        writeDouble(a);
+        writeDouble(b);
+        writeDouble(c);
+        writeDouble(d);
+    }
+
     // === Draw commands ===
 
-    public void writeDrawRange(int vboIndex, int startVertex, int vertexCount, boolean hasBrightness) {
-        ensureCapacity(20);
+    public void writeDrawRange(int vboIndex) {
+        ensureCapacity(8);
         writeInt(GLCommand.DRAW_RANGE);
         writeInt(vboIndex);
-        writeInt(startVertex);
-        writeInt(vertexCount);
-        writeInt(hasBrightness ? 1 : 0);
     }
 
     /**
@@ -562,51 +577,21 @@ public final class CommandBuffer {
      * Used for immediate mode VBOs to restore GL_CURRENT_COLOR, GL_CURRENT_NORMAL, GL_CURRENT_TEXTURE_COORDS.
      *
      * @param vboIndex Index into ownedVbos array
-     * @param startVertex First vertex to draw
-     * @param vertexCount Number of vertices to draw
-     * @param hasBrightness True if VBO has brightness/lightmap data
-     * @param hasColor True if color should be restored after draw
-     * @param hasNormals True if normal should be restored after draw
-     * @param hasTexture True if texcoord should be restored after draw
-     * @param lastColorR Last vertex's red color component
-     * @param lastColorG Last vertex's green color component
-     * @param lastColorB Last vertex's blue color component
-     * @param lastColorA Last vertex's alpha color component
-     * @param lastNormalX Last vertex's normal X
-     * @param lastNormalY Last vertex's normal Y
-     * @param lastNormalZ Last vertex's normal Z
-     * @param lastTexS Last vertex's texture S coordinate
-     * @param lastTexT Last vertex's texture T coordinate
      */
     public void writeDrawRangeRestore(
-        int vboIndex, int startVertex, int vertexCount,
-        boolean hasBrightness, boolean hasColor, boolean hasNormals, boolean hasTexture,
-        float lastColorR, float lastColorG, float lastColorB, float lastColorA,
-        float lastNormalX, float lastNormalY, float lastNormalZ,
-        float lastTexS, float lastTexT
+        int vboIndex, AccumulatedDraw.RestoreData restoreData
     ) {
-        ensureCapacity(56);
+        ensureCapacity(28);
         writeInt(GLCommand.DRAW_RANGE_RESTORE);
         writeInt(vboIndex);
-        writeInt(startVertex);
-        writeInt(vertexCount);
-        int flags = (hasBrightness ? FLAG_HAS_BRIGHTNESS : 0)
-                  | (hasColor ? FLAG_HAS_COLOR : 0)
-                  | (hasNormals ? FLAG_HAS_NORMALS : 0)
-                  | (hasTexture ? FLAG_HAS_TEXTURE : 0);
-        writeInt(flags);
-        // Last color (4 floats = 16 bytes)
-        writeFloat(lastColorR);
-        writeFloat(lastColorG);
-        writeFloat(lastColorB);
-        writeFloat(lastColorA);
-        // Last normal (3 floats = 12 bytes)
-        writeFloat(lastNormalX);
-        writeFloat(lastNormalY);
-        writeFloat(lastNormalZ);
+        writeInt(restoreData.flags);
+        // Last color (4 bytes)
+        writeInt(restoreData.lastColor);
+        // Last normal (4 bytes)
+        writeInt(restoreData.lastNormal);
         // Last texcoord (2 floats = 8 bytes)
-        writeFloat(lastTexS);
-        writeFloat(lastTexT);
+        writeFloat(restoreData.lastTexCoordU);
+        writeFloat(restoreData.lastTexCoordV);
     }
 
     public void writeCallList(int listId) {
@@ -615,6 +600,35 @@ public final class CommandBuffer {
         writeInt(listId);
     }
 
+    public void writeDrawArrays(int mode, int start, int count) {
+        ensureCapacity(16);
+        writeInt(GLCommand.DRAW_ARRAYS);
+        writeInt(mode);
+        writeInt(start);
+        writeInt(count);
+    }
+
+    public void writeDrawElements(int mode, int indices_count, int type, long indices_buffer_offset) {
+        ensureCapacity(24);
+        writeInt(GLCommand.DRAW_ELEMENTS);
+        writeInt(mode);
+        writeInt(indices_count);
+        writeInt(type);
+        writeLong(indices_buffer_offset);
+    }
+
+    public void writeBindVBO(int vbo) {
+        ensureCapacity(8);
+        writeInt(GLCommand.BIND_VBO);
+        writeInt(vbo);
+    }
+
+    public void writeBindVAO(int vao) {
+        ensureCapacity(8);
+        writeInt(GLCommand.BIND_VAO);
+        writeInt(vao);
+    }
+
     public void writeDrawBuffer(int mode) {
         ensureCapacity(8);
         writeInt(GLCommand.DRAW_BUFFER);
@@ -685,6 +699,12 @@ public final class CommandBuffer {
         return value;
     }
 
+    public long readLong() {
+        final long value = memGetLong(readPointer);
+        readPointer += 8;
+        return value;
+    }
+
     /**
      * Read a float from the current position.
      */

src/main/java/com/gtnewhorizons/angelica/glsm/recording/CommandBufferExecutor.java

@@ -1,17 +1,20 @@
 package com.gtnewhorizons.angelica.glsm.recording;
 
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
+import com.gtnewhorizon.gtnhlib.client.opengl.UniversalVAO;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFlags;
 import com.gtnewhorizons.angelica.glsm.DisplayListManager;
 import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import com.gtnewhorizons.angelica.glsm.recording.commands.DisplayListCommand;
 import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL15;
 
 import java.nio.ByteBuffer;
+import java.nio.DoubleBuffer;
 import java.nio.FloatBuffer;
 import java.nio.IntBuffer;
 
 import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.*;
-import static com.gtnewhorizons.angelica.glsm.recording.CommandBuffer.*;
 
 /**
  * Executes commands from a CommandBuffer
@@ -23,6 +26,8 @@ public final class CommandBufferExecutor {
     private static final FloatBuffer MATRIX_BUFFER = BufferUtils.createFloatBuffer(16);
     // Static reusable buffer for fog/light/material params
     private static final FloatBuffer PARAMS_BUFFER = BufferUtils.createFloatBuffer(4);
+    // Static reusable buffer for clip plane equation
+    private static final DoubleBuffer PARAMS_DOUBLE_BUFFER = BufferUtils.createDoubleBuffer(4);
     // Static reusable buffer for draw buffers
     private static final int MAX_DRAW_BUFFERS = 8;
     private static final IntBuffer DRAW_BUFFERS_BUFFER = BufferUtils.createIntBuffer(MAX_DRAW_BUFFERS);
@@ -34,7 +39,7 @@ public final class CommandBufferExecutor {
      * @param complexObjects Array of complex objects (TexImage2DCmd, etc.)
      * @param ownedVbos Array of VBOs owned by the display list (indexed by DrawRange commands)
      */
-    public static void execute(ByteBuffer buffer, Object[] complexObjects, VertexBuffer[] ownedVbos) {
+    public static void execute(ByteBuffer buffer, Object[] complexObjects, DisplayListVBO ownedVbos) {
         long ptr = memAddress(buffer);
         final long end = ptr + buffer.limit();
 
@@ -194,6 +199,14 @@ public final class CommandBufferExecutor {
                     ptr += 16;
                     GLStateManager.glViewport(x, y, width, height);
                 }
+                case GLCommand.SCISSOR -> {
+                    final int x = memGetInt(ptr);
+                    final int y = memGetInt(ptr + 4);
+                    final int width = memGetInt(ptr + 8);
+                    final int height = memGetInt(ptr + 12);
+                    ptr += 16;
+                    GLStateManager.glScissor(x, y, width, height);
+                }
                 case GLCommand.BLEND_FUNC -> {
                     final int srcRgb = memGetInt(ptr);
                     final int dstRgb = memGetInt(ptr + 4);
@@ -447,51 +460,55 @@ public final class CommandBufferExecutor {
                     GLStateManager.glMaterial(face, pname, PARAMS_BUFFER);
                 }
 
+                case GLCommand.CLIP_PLANE -> {
+                    final int plane = memGetInt(ptr);
+                    final double a = memGetDouble(ptr + 4);
+                    final double b = memGetDouble(ptr + 12);
+                    final double c = memGetDouble(ptr + 20);
+                    final double d = memGetDouble(ptr + 28);
+                    ptr += 36;
+                    PARAMS_DOUBLE_BUFFER.clear();
+                    PARAMS_DOUBLE_BUFFER.put(a).put(b).put(c).put(d);
+                    PARAMS_DOUBLE_BUFFER.flip();
+                    GLStateManager.glClipPlane(plane, PARAMS_DOUBLE_BUFFER);
+                }
+
                 // === Draw commands ===
                 case GLCommand.DRAW_RANGE -> {
                     final int vboIndex = memGetInt(ptr);
-                    final int start = memGetInt(ptr + 4);
-                    final int count = memGetInt(ptr + 8);
-                    final boolean hasBrightness = memGetInt(ptr + 12) != 0;
-                    ptr += 16;
-                    final VertexBuffer vbo = ownedVbos[vboIndex];
-                    vbo.setupState();
-                    vbo.draw(start, count);
-                    vbo.cleanupState();
+                    ptr += 4;
+                    ownedVbos.render(vboIndex);
                 }
                 case GLCommand.DRAW_RANGE_RESTORE -> {
                     // Draw VBO range then restore GL current state from last vertex attributes
                     final int vboIndex = memGetInt(ptr);
-                    final int start = memGetInt(ptr + 4);
-                    final int count = memGetInt(ptr + 8);
-                    final int flags = memGetInt(ptr + 12);
+                    final int flags = memGetInt(ptr + 4);
 
                     // Draw the VBO
-                    final VertexBuffer vbo = ownedVbos[vboIndex];
-                    vbo.setupState();
-                    vbo.draw(start, count);
-                    vbo.cleanupState();
+                    ownedVbos.render(vboIndex);
 
                     // Restore attributes based on flags
-                    if ((flags & FLAG_HAS_COLOR) != 0) {
-                        final float r = memGetFloat(ptr + 16);
-                        final float g = memGetFloat(ptr + 20);
-                        final float b = memGetFloat(ptr + 24);
-                        final float a = memGetFloat(ptr + 28);
-                        GLStateManager.glColor4f(r, g, b, a);
+                    if ((flags & VertexFlags.COLOR_BIT) != 0) {
+                        final int color = memGetInt(ptr + 8);
+                        byte a = (byte) ((color >> 24) & 0xFF);
+                        byte r = (byte) ((color >> 16) & 0xFF);
+                        byte g = (byte) ((color >> 8) & 0xFF);
+                        byte b = (byte) ((color & 0xFF));
+                        GLStateManager.glColor4ub(r, g, b, a);
                     }
-                    if ((flags & FLAG_HAS_NORMALS) != 0) {
-                        final float nx = memGetFloat(ptr + 32);
-                        final float ny = memGetFloat(ptr + 36);
-                        final float nz = memGetFloat(ptr + 40);
+                    if ((flags & VertexFlags.NORMAL_BIT) != 0) {
+                        final int normal = memGetInt(ptr + 12);
+                        float nx = (byte)(normal)       / 127.0f;
+                        float ny = (byte)(normal >> 8)  / 127.0f;
+                        float nz = (byte)(normal >> 16) / 127.0f;
                         GLStateManager.glNormal3f(nx, ny, nz);
                     }
-                    if ((flags & FLAG_HAS_TEXTURE) != 0) {
-                        final float s = memGetFloat(ptr + 44);
-                        final float t = memGetFloat(ptr + 48);
+                    if ((flags & VertexFlags.TEXTURE_BIT) != 0) {
+                        final float s = memGetFloat(ptr + 16);
+                        final float t = memGetFloat(ptr + 20);
                         GLStateManager.glTexCoord2f(s, t);
                     }
-                    ptr += 52;  // Skip full command size (56 - 4 for cmd already read)
+                    ptr += 24;  // Skip full command size (28 - 4 for cmd already read)
                 }
                 case GLCommand.CALL_LIST -> {
                     final int listId = memGetInt(ptr);
@@ -513,6 +530,22 @@ public final class CommandBufferExecutor {
                     ptr += 4 * MAX_DRAW_BUFFERS;
                     GLStateManager.glDrawBuffers(DRAW_BUFFERS_BUFFER);
                 }
+                case GLCommand.DRAW_ARRAYS -> {
+                    GLStateManager.glDrawArrays(memGetInt(ptr), memGetInt(ptr + 4), memGetInt(ptr + 8));
+                    ptr += 12;
+                }
+                case GLCommand.DRAW_ELEMENTS -> {
+                    GLStateManager.glDrawElements(memGetInt(ptr), memGetInt(ptr + 4), memGetInt(ptr + 8), memGetLong(ptr + 12));
+                    ptr += 20;
+                }
+                case GLCommand.BIND_VBO -> {
+                    GLStateManager.glBindBuffer(GL15.GL_ARRAY_BUFFER, memGetInt(ptr));
+                    ptr += 4;
+                }
+                case GLCommand.BIND_VAO -> {
+                    GLStateManager.glBindVertexArray(memGetInt(ptr));
+                    ptr += 4;
+                }
 
                 // === Complex object reference ===
                 case GLCommand.COMPLEX_REF -> {

src/main/java/com/gtnewhorizons/angelica/glsm/recording/CommandBufferProcessor.java

@@ -17,73 +17,6 @@ public final class CommandBufferProcessor {
 
     private CommandBufferProcessor() {}
 
-    public static void processCommandForOptimization(int opcode, CommandBuffer raw, BufferTransformOptimizer opt, CommandBuffer out) {
-        switch (opcode) {
-            // === MultMatrix - already collapsed transforms from flushMatrix() ===
-            case GLCommand.MULT_MATRIX -> {
-                raw.readMatrix4f(tempMatrix);
-                opt.multMatrix(tempMatrix);          // accumulated = accumulated * tempMatrix
-                out.writeMultMatrix(tempMatrix);     // Copy to output
-                opt.markLastEmittedAsAccumulated();  // lastEmitted = accumulated (what GL now has)
-            }
-
-            // === Load commands - flush pending, emit, reset accumulator ===
-            case GLCommand.LOAD_IDENTITY -> {
-                opt.emitPendingTransform(out);     // Emit any pending transforms first
-                out.writeLoadIdentity();           // Always emit LoadIdentity
-                opt.loadIdentity();                // Reset accumulated to identity
-                opt.resetLastEmitted();            // Reset lastEmitted to identity
-                opt.checkAndClearAbsoluteMatrix(); // Clear the flag if set
-            }
-            case GLCommand.LOAD_MATRIX -> {
-                raw.readMatrix4f(tempMatrix);
-                opt.emitPendingTransform(out);
-                out.writeLoadMatrix(tempMatrix);
-                opt.loadIdentity();
-                opt.resetLastEmitted();  // Reset lastEmitted to identity
-                opt.markAbsoluteMatrix();
-            }
-
-            // === Stack operations - flush/update optimizer state and copy ===
-            case GLCommand.PUSH_MATRIX -> {
-                opt.emitPendingTransform(out);
-                opt.push();
-                // Reset accumulated/lastEmitted to identity after push.
-                opt.loadIdentity();
-                opt.resetLastEmitted();
-                out.writePushMatrix();
-            }
-            case GLCommand.POP_MATRIX -> {
-                opt.pop();
-                out.writePopMatrix();
-            }
-
-            // === Barriers - emit pending transform before copying ===
-            case GLCommand.MATRIX_MODE -> {
-                final int mode = raw.readInt();
-                opt.emitPendingTransform(out);  // Pending transforms apply to OLD mode
-                out.writeMatrixMode(mode);
-                opt.loadIdentity();             // Reset accumulated for new mode
-                opt.resetLastEmitted();         // Reset lastEmitted for new mode
-            }
-            case GLCommand.CALL_LIST -> {
-                final int listId = raw.readInt();
-                opt.emitPendingTransform(out);
-                out.writeCallList(listId);
-            }
-            case GLCommand.PUSH_ATTRIB -> {
-                final int mask = raw.readInt();
-                if ((mask & GL11.GL_TRANSFORM_BIT) != 0) {
-                    opt.emitPendingTransform(out);
-                }
-                out.writePushAttrib(mask);
-            }
-
-            // === All other commands - just copy ===
-            default -> copyCommandData(opcode, raw, out);
-        }
-    }
-
     /**
      * Copy a complete command (opcode already read) from raw to final buffer.
      */
@@ -134,6 +67,7 @@ public final class CommandBufferProcessor {
 
             // Four int commands
             case GLCommand.VIEWPORT -> out.writeViewport(raw.readInt(), raw.readInt(), raw.readInt(), raw.readInt());
+            case GLCommand.SCISSOR -> out.writeScissor(raw.readInt(), raw.readInt(), raw.readInt(), raw.readInt());
             case GLCommand.BLEND_FUNC -> out.writeBlendFunc(raw.readInt(), raw.readInt(), raw.readInt(), raw.readInt());
             case GLCommand.COLOR_MASK -> out.writeColorMask(raw.readInt() != 0, raw.readInt() != 0, raw.readInt() != 0, raw.readInt() != 0);
             case GLCommand.STENCIL_FUNC_SEPARATE -> out.writeStencilFuncSeparate(raw.readInt(), raw.readInt(), raw.readInt(), raw.readInt());
@@ -209,9 +143,23 @@ public final class CommandBufferProcessor {
                 out.writeMaterial(face, pname, fb);
             }
 
+            // Clip plane command (4 doubles)
+            case GLCommand.CLIP_PLANE -> {
+                final int plane = raw.readInt();
+                final double a = raw.readDouble();
+                final double b = raw.readDouble();
+                final double c = raw.readDouble();
+                final double d = raw.readDouble();
+                out.writeClipPlane(plane, a, b, c, d);
+            }
+
             // Draw/call commands
-            case GLCommand.DRAW_RANGE -> out.writeDrawRange(raw.readInt(), raw.readInt(), raw.readInt(), raw.readInt() != 0);
+            case GLCommand.DRAW_RANGE -> out.writeDrawRange(raw.readInt());
             case GLCommand.CALL_LIST -> out.writeCallList(raw.readInt());
+            case GLCommand.DRAW_ARRAYS -> out.writeDrawArrays(raw.readInt(), raw.readInt(), raw.readInt());
+            case GLCommand.DRAW_ELEMENTS -> out.writeDrawElements(raw.readInt(), raw.readInt(), raw.readInt(), raw.readLong());
+            case GLCommand.BIND_VBO -> out.writeBindVBO(raw.readInt());
+            case GLCommand.BIND_VAO -> out.writeBindVAO(raw.readInt());
 
             // Complex object reference - transfer the object to output buffer
             case GLCommand.COMPLEX_REF -> {
@@ -223,94 +171,4 @@ public final class CommandBufferProcessor {
             default -> LOGGER.warn("[CommandBufferProcessor] Unknown opcode in buffer copy: {}", opcode);
         }
     }
-
-    /**
-     * Lightweight transform optimizer for buffer-to-buffer processing.
-     * Tracks accumulated transform (mode-agnostic) and emits MultMatrix commands when needed.
-     *
-     * <p>This optimizer processes raw transform commands (TRANSLATE, ROTATE, SCALE) and
-     * collapses them into single MultMatrix commands at barriers. It must stay synchronized
-     * with the relativeTransform tracking in DisplayListManager - both systems must reset
-     * at the same barriers (MatrixMode, LoadIdentity, LoadMatrix, Push/Pop).</p>
-     */
-    public static class BufferTransformOptimizer {
-        private final Matrix4f accumulated = new Matrix4f();
-        private final Matrix4f lastEmitted = new Matrix4f();
-        private final Matrix4f delta = new Matrix4f();  // Reused for delta computation
-        private final Deque<Matrix4f> stack = new ArrayDeque<>();
-        private boolean absoluteMatrixFlag = false;
-
-        public BufferTransformOptimizer() {
-            accumulated.identity();
-            lastEmitted.identity();
-        }
-
-        public void multMatrix(Matrix4f m) {
-            accumulated.mul(m);
-        }
-
-        public void loadIdentity() {
-            accumulated.identity();
-        }
-
-        public void push() {
-            stack.push(new Matrix4f(accumulated));
-        }
-
-        public void pop() {
-            if (!stack.isEmpty()) {
-                accumulated.set(stack.pop());
-                lastEmitted.set(accumulated);
-            } else {
-                accumulated.identity();
-                lastEmitted.identity();
-            }
-        }
-
-        public boolean isIdentity() {
-            return DisplayListManager.isIdentity(accumulated);
-        }
-
-        public void markAbsoluteMatrix() {
-            absoluteMatrixFlag = true;
-        }
-
-        public boolean checkAndClearAbsoluteMatrix() {
-            final boolean was = absoluteMatrixFlag;
-            absoluteMatrixFlag = false;
-            return was;
-        }
-
-        public void resetLastEmitted() {
-            lastEmitted.identity();
-        }
-
-        public void setLastEmitted(Matrix4f m) {
-            lastEmitted.set(m);
-        }
-
-        public void markLastEmittedAsAccumulated() {
-            lastEmitted.set(accumulated);
-        }
-
-        public void emitPendingTransform(CommandBuffer out) {
-            if (!accumulated.equals(lastEmitted)) {
-                emitTransformTo(out, accumulated);
-            }
-        }
-
-        public void emitTransformTo(CommandBuffer out, Matrix4f target) {
-            if (target.equals(lastEmitted)) {
-                return;
-            }
-
-            if (DisplayListManager.isIdentity(lastEmitted)) {
-                out.writeMultMatrix(target);
-            } else {
-                delta.set(lastEmitted).invert().mul(target);
-                out.writeMultMatrix(delta);
-            }
-            lastEmitted.set(target);
-        }
-    }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/recording/CommandRecorder.java

@@ -9,7 +9,7 @@ import java.nio.IntBuffer;
 /**
  * Records GL commands to a CommandBuffer during display list compilation.
  */
-public class CommandRecorder {
+public final class CommandRecorder {
     private final CommandBuffer buffer;
     private int commandCount;
 
@@ -172,6 +172,11 @@ public class CommandRecorder {
         commandCount++;
     }
 
+    public void recordScissor(int x, int y, int width, int height) {
+        buffer.writeScissor(x, y, width, height);
+        commandCount++;
+    }
+
     public void recordPointSize(float size) {
         buffer.writePointSize(size);
         commandCount++;
@@ -287,6 +292,11 @@ public class CommandRecorder {
         commandCount++;
     }
 
+    public void recordClipPlane(int plane, double a, double b, double c, double d) {
+        buffer.writeClipPlane(plane, a, b, c, d);
+        commandCount++;
+    }
+
     public void recordStencilFunc(int func, int ref, int mask) {
         buffer.writeStencilFunc(func, ref, mask);
         commandCount++;
@@ -337,6 +347,26 @@ public class CommandRecorder {
         commandCount++;
     }
 
+    public void recordDrawArrays(int mode, int start, int count) {
+        buffer.writeDrawArrays(mode, start, count);
+        commandCount++;
+    }
+
+    public void recordDrawElements(int mode, int indices_count, int type, long indices_buffer_offset) {
+        buffer.writeDrawElements(mode, indices_count, type, indices_buffer_offset);
+        commandCount++;
+    }
+
+    public void recordBindVBO(int vbo) {
+        buffer.writeBindVBO(vbo);
+        commandCount++;
+    }
+
+    public void recordBindVAO(int vao) {
+        buffer.writeBindVAO(vao);
+        commandCount++;
+    }
+
     public void recordComplexCommand(DisplayListCommand cmd) {
         buffer.writeComplexRef(cmd);
         commandCount++;

src/main/java/com/gtnewhorizons/angelica/glsm/recording/CompiledDisplayList.java

@@ -1,6 +1,6 @@
 package com.gtnewhorizons.angelica.glsm.recording;
 
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
+import com.gtnewhorizons.angelica.glsm.DisplayListManager;
 import com.gtnewhorizons.angelica.glsm.recording.commands.DisplayListCommand;
 import it.unimi.dsi.fastutil.ints.Int2IntMap;
 import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
@@ -30,9 +30,9 @@ public final class CompiledDisplayList {
 
     private final ByteBuffer commandBuffer;     // Off-heap command storage, must be freed
     private final Object[] complexObjects;      // Complex commands (TexImage2D, etc.)
-    private final VertexBuffer[] ownedVbos;     // GPU resources referenced by index
+    private final DisplayListVBO ownedVbos;     // GPU resources referenced by index
 
-    public CompiledDisplayList(ByteBuffer commandBuffer, Object[] complexObjects, VertexBuffer[] ownedVbos) {
+    public CompiledDisplayList(ByteBuffer commandBuffer, Object[] complexObjects, DisplayListVBO ownedVbos) {
         this.commandBuffer = commandBuffer;
         this.complexObjects = complexObjects;
         this.ownedVbos = ownedVbos;
@@ -62,11 +62,7 @@ public final class CompiledDisplayList {
 
         // Close VBOs
         if (ownedVbos != null) {
-            for (VertexBuffer vbo : ownedVbos) {
-                if (vbo != null) {
-                    vbo.close();
-                }
-            }
+            ownedVbos.delete();
         }
 
         // Free the command buffer (off-heap memory)
@@ -89,10 +85,7 @@ public final class CompiledDisplayList {
         return complexObjects;
     }
 
-    /**
-     * Get owned VBOs for inlining into another display list.
-     */
-    public VertexBuffer[] getOwnedVbos() {
+    public DisplayListVBO getOwnedVbos() {
         return ownedVbos;
     }
 
@@ -112,7 +105,7 @@ public final class CompiledDisplayList {
         while (ptr < end) {
             final int cmd = memGetInt(ptr);
             counts.mergeInt(cmd, 1, Integer::sum);
-            ptr += getCommandSize(cmd, ptr);
+            ptr += GLCommand.getCommandSize(cmd, ptr);
         }
         return counts;
     }
@@ -131,74 +124,13 @@ public final class CompiledDisplayList {
         while (ptr < end) {
             final int cmd = memGetInt(ptr);
             opcodes.add(cmd);
-            ptr += getCommandSize(cmd, ptr);
+            ptr += GLCommand.getCommandSize(cmd, ptr);
         }
         return opcodes;
     }
 
-    /**
-     * Get size of a command in bytes (including the opcode).
-     */
-    private static int getCommandSize(int cmd, long ptr) {
-        return switch (cmd) {
-            // Opcode-only commands (4 bytes)
-            case GLCommand.LOAD_IDENTITY, GLCommand.PUSH_MATRIX, GLCommand.POP_MATRIX -> 4;
-
-            // Single int commands (8 bytes)
-            case GLCommand.ENABLE, GLCommand.DISABLE, GLCommand.CLEAR, GLCommand.CLEAR_STENCIL,
-                 GLCommand.CULL_FACE, GLCommand.DEPTH_FUNC, GLCommand.SHADE_MODEL, GLCommand.LOGIC_OP,
-                 GLCommand.MATRIX_MODE, GLCommand.ACTIVE_TEXTURE, GLCommand.USE_PROGRAM,
-                 GLCommand.PUSH_ATTRIB, GLCommand.POP_ATTRIB, GLCommand.STENCIL_MASK,
-                 GLCommand.DEPTH_MASK, GLCommand.FRONT_FACE, GLCommand.POINT_SIZE, GLCommand.LINE_WIDTH,
-                 GLCommand.CALL_LIST, GLCommand.COMPLEX_REF -> 8;
-
-            // Two int commands (12 bytes)
-            case GLCommand.BIND_TEXTURE, GLCommand.POLYGON_MODE, GLCommand.COLOR_MATERIAL,
-                 GLCommand.LINE_STIPPLE, GLCommand.STENCIL_MASK_SEPARATE, GLCommand.FOGI,
-                 GLCommand.HINT, GLCommand.POLYGON_OFFSET, GLCommand.ALPHA_FUNC, GLCommand.FOGF,
-                 GLCommand.LIGHT_MODELF, GLCommand.LIGHT_MODELI -> 12;
-
-            // Three int commands (16 bytes)
-            case GLCommand.STENCIL_FUNC, GLCommand.STENCIL_OP, GLCommand.TEX_PARAMETERI,
-                 GLCommand.LIGHTF, GLCommand.LIGHTI,
-                 GLCommand.MATERIALF, GLCommand.TEX_PARAMETERF -> 16;
-
-            // Four int commands (20 bytes)
-            case GLCommand.VIEWPORT, GLCommand.BLEND_FUNC, GLCommand.COLOR_MASK,
-                 GLCommand.STENCIL_FUNC_SEPARATE, GLCommand.STENCIL_OP_SEPARATE,
-                 GLCommand.COLOR, GLCommand.CLEAR_COLOR, GLCommand.BLEND_COLOR,
-                 GLCommand.DRAW_RANGE -> 20;
-
-            // DRAW_RANGE_RESTORE: 56 bytes
-            // [cmd:4][vboIndex:4][start:4][count:4][flags:4][color:16f][normal:12f][texcoord:8f]
-            case GLCommand.DRAW_RANGE_RESTORE -> 56;
-
-            // DRAW_BUFFER: 8 bytes [cmd:4][mode:4]
-            case GLCommand.DRAW_BUFFER -> 8;
-
-            // DRAW_BUFFERS: 40 bytes [cmd:4][count:4][bufs:4*8]
-            case GLCommand.DRAW_BUFFERS -> 40;
-
-            // Double commands
-            case GLCommand.TRANSLATE, GLCommand.SCALE -> 28;  // cmd + 3 doubles
-            case GLCommand.CLEAR_DEPTH -> 12;  // cmd + 1 double
-            case GLCommand.ROTATE -> 36;  // cmd + 4 doubles
-            case GLCommand.ORTHO, GLCommand.FRUSTUM -> 52;  // cmd + 6 doubles
-
-            // Matrix commands
-            case GLCommand.MULT_MATRIX, GLCommand.LOAD_MATRIX -> 68;  // cmd + 16 floats
-
-            // Buffer commands (variable, read count)
-            case GLCommand.FOG, GLCommand.LIGHT_MODEL -> {
-                final int count = memGetInt(ptr + 8);  // pname at +4, count at +8
-                yield 12 + count * 4;
-            }
-            case GLCommand.LIGHT, GLCommand.MATERIAL -> {
-                final int count = memGetInt(ptr + 12);  // light/face at +4, pname at +8, count at +12
-                yield 16 + count * 4;
-            }
-
-            default -> throw new IllegalStateException("Unknown command: " + cmd);
-        };
+    @Override
+    public String toString() {
+        return DisplayListManager.getCompiledDisplayListString(0, this, null);
     }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/recording/DisplayListVBO.java

@@ -0,0 +1,58 @@
+package com.gtnewhorizons.angelica.glsm.recording;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.IVertexArrayObject;
+
+/**
+ * A class that stores multiple vertex formats & their corresponding buffers.
+ */
+public final class DisplayListVBO {
+
+    private final SubVBO[] vbos;
+
+    DisplayListVBO(SubVBO[] vbos) {
+        this.vbos = vbos;
+    }
+
+    public void delete() {
+        for (SubVBO vbo : vbos) {
+            vbo.delete();
+        }
+    }
+
+    public SubVBO[] getVBOs() {
+        return vbos;
+    }
+
+    public void render(int index) {
+        vbos[index].render();
+    }
+
+    public static final class SubVBO {
+
+        private final IVertexArrayObject vao;
+        private final int drawMode;
+        private final int start;
+        private final int count;
+
+        public SubVBO(IVertexArrayObject vao, int drawMode, int start, int count) {
+            this.vao = vao;
+            this.drawMode = drawMode;
+            this.start = start;
+            this.count = count;
+        }
+
+        public void delete() {
+            vao.delete();
+        }
+
+        public void render() {
+            vao.bind();
+            vao.draw(drawMode, start, count);
+            vao.unbind();
+        }
+
+        public IVertexArrayObject getVAO() {
+            return vao;
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/DisplayListVBOBuilder.java

@@ -0,0 +1,131 @@
+package com.gtnewhorizons.angelica.glsm.recording;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.IVertexArrayObject;
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.IndexBuffer;
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.IndexedVAO;
+import com.gtnewhorizon.gtnhlib.client.renderer.vao.VAOManager;
+import com.gtnewhorizon.gtnhlib.client.renderer.vbo.IVertexBuffer;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.DefaultVertexFormat;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFlags;
+import com.gtnewhorizon.gtnhlib.client.renderer.vertex.VertexFormat;
+import org.lwjgl.opengl.GL11;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAddress0;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memAlloc;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memCopy;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memFree;
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.nmemFree;
+
+/**
+ * Compiles multiple ByteBuffers of the same Vertex format into a VBO. Any buffer added to the builder will be freed afterward.
+ */
+public final class DisplayListVBOBuilder {
+
+    // Removes the need for a HashMap. Since it's only an array of 16 values, this should be faster
+    private final List<FormatData>[] formats = new List[VertexFlags.BITSET_SIZE];
+    private int count;
+
+    public DisplayListVBOBuilder addDraw(VertexFormat format, int drawMode, List<ByteBuffer> buffers) {
+        List<FormatData> data = formats[format.getVertexFlags()];
+        if (data == null) {
+            data = new ArrayList<>();
+            formats[format.getVertexFlags()] = data;
+        }
+        data.add(new FormatData(buffers, drawMode, count));
+        count++;
+        return this;
+    }
+
+    public DisplayListVBOBuilder addDraws(List<AccumulatedDraw> draws) {
+        for (AccumulatedDraw draw : draws) {
+            addDraw(draw.format, draw.drawMode, draw.drawBuffers);
+        }
+        return this;
+    }
+
+    public DisplayListVBO build() {
+        final DisplayListVBO.SubVBO[] vbos = new DisplayListVBO.SubVBO[count];
+        final ArrayList<ByteBuffer> allBuffers = new ArrayList<>();
+        for (int i = 0; i < VertexFlags.BITSET_SIZE; i++) {
+            List<FormatData> formatData = formats[i];
+            if (formatData == null) continue;
+            final VertexFormat format = DefaultVertexFormat.ALL_FORMATS[i];
+            int start = 0;
+            final IVertexArrayObject vao = VAOManager.createStorageVAO(format, -1, 0); // drawMode will be ignored
+            final IVertexBuffer vbo = vao.getVBO();
+            for (FormatData data : formatData) {
+                int vertexCount;
+                final List<ByteBuffer> drawBuffers = data.buffers;
+                if (drawBuffers.size() == 1) {
+                    final ByteBuffer buffer = drawBuffers.get(0);
+                    allBuffers.add(buffer);
+                    vertexCount = format.getVertexCount(buffer);
+                } else {
+                    allBuffers.addAll(drawBuffers);
+                    int size = 0;
+                    for (ByteBuffer buffer : drawBuffers) {
+                        size += buffer.remaining();
+                    }
+                    vertexCount = format.getVertexCount(size);
+                }
+                if (data.drawMode == GL11.GL_QUADS) {
+                    final IVertexArrayObject indexedVAO = new IndexedVAO(vbo, IndexBuffer.convertQuadsToTrigs(start, start + vertexCount));
+                    vbos[data.drawIndex] = new DisplayListVBO.SubVBO(indexedVAO, GL11.GL_TRIANGLES, 0, vertexCount / 4 * 6);
+                } else {
+                    vbos[data.drawIndex] = new DisplayListVBO.SubVBO(vao, data.drawMode, start, vertexCount);
+                }
+
+
+                start += vertexCount;
+            }
+            ByteBuffer bigBuffer = mergeAndDelete(allBuffers);
+            vbo.allocate(bigBuffer, start);
+            memFree(bigBuffer);
+
+            allBuffers.clear();
+        }
+        return new DisplayListVBO(vbos);
+    }
+
+    private static ByteBuffer mergeAndDelete(List<ByteBuffer> buffers) {
+        if (buffers.size() == 1) {
+            return buffers.get(0);
+        }
+        int needed = 0;
+        for (ByteBuffer buffer : buffers) {
+            needed += buffer.remaining();
+        }
+
+        ByteBuffer out = memAlloc(needed);
+        long dst = memAddress0(out);
+
+        for (ByteBuffer buffer : buffers) {
+            final int len = buffer.limit();
+            final long address = memAddress0(buffer);
+            memCopy(address, dst, len);
+            dst += len;
+
+            nmemFree(address);
+        }
+
+        out.limit(needed);
+        return out;
+    }
+
+    private static final class FormatData {
+
+        private final List<ByteBuffer> buffers;
+        private final int drawMode;
+        private final int drawIndex;
+
+        public FormatData(List<ByteBuffer> buffers, int drawMode, int drawIndex) {
+            this.buffers = buffers;
+            this.drawMode = drawMode;
+            this.drawIndex = drawIndex;
+        }
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/GLCommand.java

@@ -1,5 +1,7 @@
 package com.gtnewhorizons.angelica.glsm.recording;
 
+import static com.gtnewhorizon.gtnhlib.bytebuf.MemoryUtilities.memGetInt;
+
 /**
  * Command opcodes for ByteBuffer-based display list serialization.
  * Each command has a fixed layout described in comments.
@@ -49,6 +51,7 @@ public final class GLCommand {
     public static final int COLOR_MASK = 42;         // [cmd:4][r:4][g:4][b:4][a:4] (0 or 1 each)
     public static final int STENCIL_FUNC_SEPARATE = 43; // [cmd:4][face:4][func:4][ref:4][mask:4]
     public static final int STENCIL_OP_SEPARATE = 44; // [cmd:4][face:4][sfail:4][dpfail:4][dppass:4]
+    public static final int SCISSOR = 45;             // [cmd:4][x:4][y:4][width:4][height:4]
 
     // === Float commands ===
     public static final int POINT_SIZE = 50;         // [cmd:4][size:4f]
@@ -86,18 +89,27 @@ public final class GLCommand {
     public static final int LIGHT = 91;              // [cmd:4][light:4][pname:4][count:4][params:16f] = 32 bytes
     public static final int LIGHT_MODEL = 92;        // [cmd:4][pname:4][count:4][params:16f] = 28 bytes
     public static final int MATERIAL = 93;           // [cmd:4][face:4][pname:4][count:4][params:16f] = 32 bytes
+    public static final int CLIP_PLANE = 94;         // [cmd:4][plane:4][a:8d][b:8d][c:8d][d:8d] = 40 bytes
 
     // === Draw commands ===
-    public static final int DRAW_RANGE = 100;        // [cmd:4][vboIndex:4][start:4][count:4][hasBrightness:4] = 20 bytes
-    public static final int CALL_LIST = 101;         // [cmd:4][listId:4] = 8 bytes
-    public static final int DRAW_BUFFER = 102;       // [cmd:4][mode:4] = 8 bytes
-    public static final int DRAW_BUFFERS = 103;      // [cmd:4][count:4][bufs:4*8] = 40 bytes (up to 8 buffers)
+    public static final int DRAW_RANGE = 100;        // [cmd:4][vboIndex:4] = 8 bytes
+    public static final int DRAW_RANGE_RESTORE = 101; // [cmd:4][vboIndex:4][flags:4][color:4][normal:4][lastTexCoord:8f] = 28 bytes
+    public static final int CALL_LIST = 102;         // [cmd:4][listId:4] = 8 bytes
+
+
+    public static final int DRAW_ARRAYS = 110;       // [cmd:4][drawMode:4][start:4][count:4] = 20 bytes
+    public static final int DRAW_ELEMENTS = 111;     // [cmd:4][mode:4][indices_count:4][type:4][indices_buffer_offset:8] = 28 bytes
+    public static final int DRAW_BUFFER = 112;       // [cmd:4][mode:4] = 8 bytes
+    public static final int DRAW_BUFFERS = 113;      // [cmd:4][count:4][bufs:4*8] = 40 bytes (up to 8 buffers)
     /**
      * Draw VBO range with attribute restoration after draw.
      * Used for immediate mode VBOs to restore GL current state (color, normal, texcoord).
      */
-    public static final int DRAW_RANGE_RESTORE = 104; // [cmd:4][vboIndex:4][start:4][count:4][flags:4]
-                                                      // [lastColor:16f][lastNormal:12f][lastTexCoord:8f] = 56 bytes
+
+
+    // === Bind commands ===
+    public static final int BIND_VBO = 120;
+    public static final int BIND_VAO = 121;
 
     // === Complex object reference ===
     public static final int COMPLEX_REF = 255;       // [cmd:4][index:4] = 8 bytes
@@ -137,6 +149,7 @@ public final class GLCommand {
             case STENCIL_OP -> "STENCIL_OP";
             case TEX_PARAMETERI -> "TEX_PARAMETERI";
             case VIEWPORT -> "VIEWPORT";
+            case SCISSOR -> "SCISSOR";
             case BLEND_FUNC -> "BLEND_FUNC";
             case COLOR_MASK -> "COLOR_MASK";
             case STENCIL_FUNC_SEPARATE -> "STENCIL_FUNC_SEPARATE";
@@ -167,13 +180,85 @@ public final class GLCommand {
             case LIGHT -> "LIGHT";
             case LIGHT_MODEL -> "LIGHT_MODEL";
             case MATERIAL -> "MATERIAL";
+            case CLIP_PLANE -> "CLIP_PLANE";
             case DRAW_RANGE -> "DRAW_RANGE";
             case CALL_LIST -> "CALL_LIST";
             case DRAW_BUFFER -> "DRAW_BUFFER";
             case DRAW_BUFFERS -> "DRAW_BUFFERS";
-            case DRAW_RANGE_RESTORE -> "DRAW_RANGE_RESTORE";
             case COMPLEX_REF -> "COMPLEX_REF";
+            case DRAW_RANGE_RESTORE -> "DRAW_RANGE_RESTORE";
+            case BIND_VAO -> "BIND_VAO";
+            case BIND_VBO -> "BIND_VBO";
             default -> "UNKNOWN(" + opcode + ")";
         };
     }
+
+    /**
+     * Get size of a command in bytes (including the opcode).
+     */
+    public static int getCommandSize(int cmd, long ptr) {
+        return switch (cmd) {
+            // Opcode-only commands (4 bytes)
+            case GLCommand.LOAD_IDENTITY, GLCommand.PUSH_MATRIX, GLCommand.POP_MATRIX -> 4;
+
+            // Single int commands (8 bytes)
+            case GLCommand.ENABLE, GLCommand.DISABLE, GLCommand.CLEAR, GLCommand.CLEAR_STENCIL,
+                 GLCommand.CULL_FACE, GLCommand.DEPTH_FUNC, GLCommand.SHADE_MODEL, GLCommand.LOGIC_OP,
+                 GLCommand.MATRIX_MODE, GLCommand.ACTIVE_TEXTURE, GLCommand.USE_PROGRAM,
+                 GLCommand.PUSH_ATTRIB, GLCommand.POP_ATTRIB, GLCommand.STENCIL_MASK,
+                 GLCommand.DEPTH_MASK, GLCommand.FRONT_FACE, GLCommand.POINT_SIZE, GLCommand.LINE_WIDTH,
+                 GLCommand.CALL_LIST, GLCommand.COMPLEX_REF, GLCommand.DRAW_RANGE, GLCommand.BIND_VBO,
+                 GLCommand.BIND_VAO -> 8;
+
+            // Two int commands (12 bytes)
+            case GLCommand.BIND_TEXTURE, GLCommand.POLYGON_MODE, GLCommand.COLOR_MATERIAL,
+                 GLCommand.LINE_STIPPLE, GLCommand.STENCIL_MASK_SEPARATE, GLCommand.FOGI,
+                 GLCommand.HINT, GLCommand.POLYGON_OFFSET, GLCommand.ALPHA_FUNC, GLCommand.FOGF,
+                 GLCommand.LIGHT_MODELF, GLCommand.LIGHT_MODELI -> 12;
+
+            // Three int commands (16 bytes)
+            case GLCommand.STENCIL_FUNC, GLCommand.STENCIL_OP, GLCommand.TEX_PARAMETERI,
+                 GLCommand.LIGHTF, GLCommand.LIGHTI,
+                 GLCommand.MATERIALF, GLCommand.TEX_PARAMETERF, GLCommand.DRAW_ARRAYS -> 16;
+
+            // Four int commands (20 bytes)
+            case GLCommand.VIEWPORT, GLCommand.BLEND_FUNC, GLCommand.COLOR_MASK,
+                 GLCommand.STENCIL_FUNC_SEPARATE, GLCommand.STENCIL_OP_SEPARATE,
+                 GLCommand.SCISSOR,
+                 GLCommand.COLOR, GLCommand.CLEAR_COLOR, GLCommand.BLEND_COLOR -> 20;
+
+            case GLCommand.DRAW_ELEMENTS -> 24;
+
+            // DRAW_RANGE_RESTORE: 28 bytes
+            case GLCommand.DRAW_RANGE_RESTORE -> 28;
+
+            // DRAW_BUFFER: 8 bytes [cmd:4][mode:4]
+            case GLCommand.DRAW_BUFFER -> 8;
+
+            // DRAW_BUFFERS: 40 bytes [cmd:4][count:4][bufs:4*8]
+            case GLCommand.DRAW_BUFFERS -> 40;
+
+            // Double commands
+            case GLCommand.TRANSLATE, GLCommand.SCALE -> 28;  // cmd + 3 doubles
+            case GLCommand.CLEAR_DEPTH -> 12;  // cmd + 1 double
+            case GLCommand.ROTATE -> 36;  // cmd + 4 doubles
+            case GLCommand.ORTHO, GLCommand.FRUSTUM -> 52;  // cmd + 6 doubles
+
+            // Matrix commands
+            case GLCommand.MULT_MATRIX, GLCommand.LOAD_MATRIX -> 68;  // cmd + 16 floats
+
+            // Buffer commands (variable, read count)
+            case GLCommand.FOG, GLCommand.LIGHT_MODEL -> {
+                final int count = memGetInt(ptr + 8);  // pname at +4, count at +8
+                yield 12 + count * 4;
+            }
+            case GLCommand.LIGHT, GLCommand.MATERIAL -> {
+                final int count = memGetInt(ptr + 12);  // light/face at +4, pname at +8, count at +12
+                yield 16 + count * 4;
+            }
+            case GLCommand.CLIP_PLANE -> 40;  // cmd + plane + 4 doubles
+
+            default -> throw new IllegalStateException("Unknown command: " + cmd);
+        };
+    }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/recording/commands/DisplayListCommand.java

@@ -17,22 +17,4 @@ public interface DisplayListCommand {
     default void delete() {
         // Most commands don't hold resources
     }
-
-    /**
-     * Handle this command during display list optimization.
-     *
-     * <p>Commands override this to implement their optimization behavior:
-     * <ul>
-     *   <li>Matrix transforms: accumulate into the optimizer, return false</li>
-     *   <li>Push/Pop: update stack, return true to emit</li>
-     *   <li>Barriers: emit pending transforms, return true to emit</li>
-     *   <li>State changes: return true to emit</li>
-     * </ul>
-     *
-     * @param ctx The optimization context providing access to transform state
-     * @return true if this command should be added to output, false if handled internally
-     */
-    default boolean handleOptimization(OptimizationContext ctx) {
-        return true;
-    }
 }

src/main/java/com/gtnewhorizons/angelica/glsm/recording/commands/DrawCommand.java

@@ -1,14 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.recording.commands;
-
-import com.github.bsideup.jabel.Desugar;
-
-/**
- * Represents a single draw call within a compiled display list.
- * Each DrawCommand corresponds to one glBegin/glEnd block.
- */
-@Desugar
-public record DrawCommand(
-    int firstVertex,
-    int vertexCount,
-    int primitiveType
-) {}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/commands/DrawRangeCmd.java

@@ -1,42 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.recording.commands;
-
-import com.github.bsideup.jabel.Desugar;
-import com.gtnewhorizon.gtnhlib.client.renderer.vbo.VertexBuffer;
-import org.jetbrains.annotations.NotNull;
-
-/**
- * Command: Draw a range of vertices from a shared VBO.
- * <p>
- * DrawRangeCmd references a shared VBO owned by CompiledDisplayList.ownedVbos.
- * Multiple DrawRangeCmds can reference different ranges within the same VBO,
- * enabling format-based batching where all draws with the same vertex format
- * share a single VBO.
- * <p>
- * Transform is NOT stored here - handled by TransformOptimizer emitting
- * MultMatrixCmd before this command during optimization.
- */
-@Desugar
-public record DrawRangeCmd(
-    VertexBuffer sharedVbo,
-    int startVertex,
-    int vertexCount,
-    boolean hasBrightness
-) implements DisplayListCommand {
-
-    @Override
-    public void execute() {
-        sharedVbo.setupState();
-        sharedVbo.draw(startVertex, vertexCount);
-        sharedVbo.cleanupState();
-    }
-
-    @Override
-    public void delete() {
-        // No-op: VBO lifetime is managed by CompiledDisplayList.ownedVbos
-    }
-
-    @Override
-    public @NotNull String toString() {
-        return "DrawRange(start=" + startVertex + ", count=" + vertexCount + ", hasBrightness=" + hasBrightness + ")";
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/recording/commands/MultMatrixCmd.java

@@ -5,7 +5,6 @@ import com.gtnewhorizons.angelica.glsm.GLStateManager;
 import org.jetbrains.annotations.NotNull;
 import org.joml.Matrix4f;
 import org.lwjgl.BufferUtils;
-import org.lwjgl.opengl.GL11;
 
 import java.nio.FloatBuffer;
 

src/main/java/com/gtnewhorizons/angelica/glsm/recording/commands/OptimizationContext.java

@@ -1,42 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.recording.commands;
-
-import org.joml.Matrix4f;
-
-/**
- * Context provided to commands during display list optimization.
- * Allows commands to interact with the transform optimizer and draw batcher.
- */
-public interface OptimizationContext {
-    /** Get the accumulated MODELVIEW transform matrix. */
-    Matrix4f getAccumulatedTransform();
-
-    /** Reset accumulated transform to identity. */
-    void loadIdentity();
-
-    /** Push current accumulated transform onto stack. */
-    void pushTransform();
-
-    /** Pop transform from stack, restoring previous accumulated value. */
-    void popTransform();
-
-    /** Emit a MultMatrix command if accumulated differs from last emitted. */
-    void emitPendingTransform();
-
-    /** Emit a MultMatrix command to reach the target transform. */
-    void emitTransformTo(Matrix4f target);
-
-    /** Add a command to the output list. */
-    void emit(DisplayListCommand cmd);
-
-    /**
-     * Mark that the GL matrix is at an absolute value (after LoadMatrix).
-     * Subsequent LoadIdentity commands must be emitted to reset to identity.
-     */
-    void markAbsoluteMatrix();
-
-    /**
-     * Check if the GL matrix is at an absolute value and clear the flag.
-     * @return true if LoadMatrix was called and not yet reset by LoadIdentity
-     */
-    boolean checkAndClearAbsoluteMatrix();
-}

src/main/java/com/gtnewhorizons/angelica/glsm/stacks/BooleanStateStack.java

@@ -22,8 +22,7 @@ public class BooleanStateStack extends BooleanState implements IStateStack<Boole
     protected int savedDepth;
 
     public BooleanStateStack(int glCap) {
-        // Most booleans default to false
-        this(glCap, false);
+        this(glCap, false, false);
     }
 
     /**
@@ -34,7 +33,18 @@ public class BooleanStateStack extends BooleanState implements IStateStack<Boole
      * @param initialState initial enabled state
      */
     public BooleanStateStack(int glCap, boolean initialState) {
-        super(glCap);
+        this(glCap, initialState, false);
+    }
+
+    /**
+     * Create a BooleanStateStack with custom initial state and FFP flag.
+     *
+     * @param glCap GL capability constant
+     * @param initialState initial enabled state
+     * @param ffpStateOnly when true, GL calls are skipped when FFP emulation is active
+     */
+    public BooleanStateStack(int glCap, boolean initialState, boolean ffpStateOnly) {
+        super(glCap, ffpStateOnly);
         this.enabled = initialState;
         stack = new boolean[GLStateManager.MAX_ATTRIB_STACK_DEPTH];
     }

src/main/java/com/gtnewhorizons/angelica/glsm/stacks/TextureUnitBooleanStateStack.java

@@ -12,12 +12,12 @@ public class TextureUnitBooleanStateStack extends BooleanStateStack {
     private final int unitIndex;
 
     public TextureUnitBooleanStateStack(int glCap, int unitIndex) {
-        super(glCap);
+        super(glCap, false, true); // All texture enable/disable states are FFP-only
         this.unitIndex = unitIndex;
     }
 
     public TextureUnitBooleanStateStack(int glCap, int unitIndex, boolean initialState) {
-        super(glCap, initialState);
+        super(glCap, initialState, true);
         this.unitIndex = unitIndex;
     }
 
@@ -41,12 +41,14 @@ public class TextureUnitBooleanStateStack extends BooleanStateStack {
         if (bypass || enabled != this.enabled) {
             if (!bypass) this.enabled = enabled;
 
-            int currentUnit = GLStateManager.getActiveTextureUnit();
-            boolean needsSwitch = currentUnit != unitIndex;
+            if (!ffpStateOnly) {
+                final int currentUnit = GLStateManager.getActiveTextureUnit();
+                final boolean needsSwitch = currentUnit != unitIndex;
 
-            if (needsSwitch) GL13.glActiveTexture(GL13.GL_TEXTURE0 + unitIndex);
-            if (enabled) GL11.glEnable(glCap); else GL11.glDisable(glCap);
-            if (needsSwitch) GL13.glActiveTexture(GL13.GL_TEXTURE0 + currentUnit);
+                if (needsSwitch) GL13.glActiveTexture(GL13.GL_TEXTURE0 + unitIndex);
+                if (enabled) GL11.glEnable(glCap); else GL11.glDisable(glCap);
+                if (needsSwitch) GL13.glActiveTexture(GL13.GL_TEXTURE0 + currentUnit);
+            }
         }
     }
 

src/main/java/com/gtnewhorizons/angelica/glsm/stacks/Vec3fStack.java

@@ -0,0 +1,47 @@
+package com.gtnewhorizons.angelica.glsm.stacks;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.stacks.IStateStack;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.joml.Vector3f;
+
+/**
+ * Stack for a Vector3f value (e.g. current normal).
+ */
+public class Vec3fStack implements IStateStack<Vec3fStack> {
+
+    private final Vector3f value;
+    private final float[][] stack;
+    private int pointer;
+
+    public Vec3fStack(Vector3f value) {
+        this.value = value;
+        stack = new float[GLStateManager.MAX_ATTRIB_STACK_DEPTH][3];
+    }
+
+    @Override
+    public Vec3fStack push() {
+        if (pointer == stack.length) {
+            throw new IllegalStateException("Stack overflow size " + (pointer + 1) + " reached");
+        }
+        stack[pointer][0] = value.x;
+        stack[pointer][1] = value.y;
+        stack[pointer][2] = value.z;
+        pointer++;
+        return this;
+    }
+
+    @Override
+    public Vec3fStack pop() {
+        if (pointer == 0) {
+            throw new IllegalStateException("Stack underflow");
+        }
+        pointer--;
+        value.set(stack[pointer][0], stack[pointer][1], stack[pointer][2]);
+        return this;
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return pointer == 0;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/stacks/Vec4fStack.java

@@ -0,0 +1,48 @@
+package com.gtnewhorizons.angelica.glsm.stacks;
+
+import com.gtnewhorizon.gtnhlib.client.renderer.stacks.IStateStack;
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.joml.Vector4f;
+
+/**
+ * Stack for a Vector4f value (e.g. current texture coordinates).
+ */
+public class Vec4fStack implements IStateStack<Vec4fStack> {
+
+    private final Vector4f value;
+    private final float[][] stack;
+    private int pointer;
+
+    public Vec4fStack(Vector4f value) {
+        this.value = value;
+        stack = new float[GLStateManager.MAX_ATTRIB_STACK_DEPTH][4];
+    }
+
+    @Override
+    public Vec4fStack push() {
+        if (pointer == stack.length) {
+            throw new IllegalStateException("Stack overflow size " + (pointer + 1) + " reached");
+        }
+        stack[pointer][0] = value.x;
+        stack[pointer][1] = value.y;
+        stack[pointer][2] = value.z;
+        stack[pointer][3] = value.w;
+        pointer++;
+        return this;
+    }
+
+    @Override
+    public Vec4fStack pop() {
+        if (pointer == 0) {
+            throw new IllegalStateException("Stack underflow");
+        }
+        pointer--;
+        value.set(stack[pointer][0], stack[pointer][1], stack[pointer][2], stack[pointer][3]);
+        return this;
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return pointer == 0;
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/states/AlphaState.java

@@ -7,7 +7,7 @@ import org.lwjgl.opengl.GL11;
 @Getter
 public class AlphaState implements ISettableState<AlphaState> {
     @Setter protected int function = GL11.GL_ALWAYS;
-    @Setter protected float reference = -1.0F;
+    @Setter protected float reference = 0.0F;
 
     @Override
     public AlphaState set(AlphaState state) {

src/main/java/com/gtnewhorizons/angelica/glsm/states/BlendState.java

@@ -3,6 +3,7 @@ package com.gtnewhorizons.angelica.glsm.states;
 import lombok.Getter;
 import lombok.Setter;
 import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL14;
 
 
 @Getter @Setter
@@ -11,6 +12,12 @@ public class BlendState implements ISettableState<BlendState> {
     protected int dstRgb = GL11.GL_ZERO;
     protected int srcAlpha = GL11.GL_ONE;
     protected int dstAlpha = GL11.GL_ZERO;
+    protected int equationRgb = GL14.GL_FUNC_ADD;
+    protected int equationAlpha = GL14.GL_FUNC_ADD;
+    protected float blendColorR = 0.0f;
+    protected float blendColorG = 0.0f;
+    protected float blendColorB = 0.0f;
+    protected float blendColorA = 0.0f;
 
     public BlendState() {}
 
@@ -39,6 +46,12 @@ public class BlendState implements ISettableState<BlendState> {
         this.dstRgb = state.dstRgb;
         this.srcAlpha = state.srcAlpha;
         this.dstAlpha = state.dstAlpha;
+        this.equationRgb = state.equationRgb;
+        this.equationAlpha = state.equationAlpha;
+        this.blendColorR = state.blendColorR;
+        this.blendColorG = state.blendColorG;
+        this.blendColorB = state.blendColorB;
+        this.blendColorA = state.blendColorA;
         return this;
     }
 
@@ -46,7 +59,13 @@ public class BlendState implements ISettableState<BlendState> {
     public boolean sameAs(Object state) {
         if (this == state) return true;
         if (!(state instanceof BlendState blendState)) return false;
-        return srcRgb == blendState.srcRgb && dstRgb == blendState.dstRgb && srcAlpha == blendState.srcAlpha && dstAlpha == blendState.dstAlpha;
+        return srcRgb == blendState.srcRgb && dstRgb == blendState.dstRgb
+            && srcAlpha == blendState.srcAlpha && dstAlpha == blendState.dstAlpha
+            && equationRgb == blendState.equationRgb && equationAlpha == blendState.equationAlpha
+            && Float.compare(blendColorR, blendState.blendColorR) == 0
+            && Float.compare(blendColorG, blendState.blendColorG) == 0
+            && Float.compare(blendColorB, blendState.blendColorB) == 0
+            && Float.compare(blendColorA, blendState.blendColorA) == 0;
     }
 
     @Override

src/main/java/com/gtnewhorizons/angelica/glsm/states/BooleanState.java

@@ -6,11 +6,22 @@ import org.lwjgl.opengl.GL11;
 
 public class BooleanState implements ISettableState<BooleanState> {
     protected final int glCap;
+    protected final boolean ffpStateOnly;
 
     @Getter protected boolean enabled;
+    protected boolean stateUnknown;
 
     public BooleanState(int glCap) {
+        this(glCap, false);
+    }
+
+    public BooleanState(int glCap, boolean ffpStateOnly) {
         this.glCap = glCap;
+        this.ffpStateOnly = ffpStateOnly;
+    }
+
+    public void setUnknownState() {
+        stateUnknown = true;
     }
 
     public void disable() {
@@ -23,15 +34,17 @@ public class BooleanState implements ISettableState<BooleanState> {
 
     public void setEnabled(boolean enabled) {
         final boolean bypass = GLStateManager.shouldBypassCache();
-        if (bypass || enabled != this.enabled || (this.glCap == GL11.GL_BLEND && GLStateManager.vendorIsAMD() && GLStateManager.isPoppingAttributes())) {
+        if (stateUnknown || bypass || enabled != this.enabled || (this.glCap == GL11.GL_BLEND && GLStateManager.vendorIsAMD() && GLStateManager.isPoppingAttributes())) {
+            stateUnknown = false;
             if (!bypass) {
                 this.enabled = enabled;
             }
-            // Always call GL - the calling method controls whether we reach here based on recording mode
-            if (enabled) {
-                GL11.glEnable(this.glCap);
-            } else {
-                GL11.glDisable(this.glCap);
+            if (!ffpStateOnly) {
+                if (enabled) {
+                    GL11.glEnable(this.glCap);
+                } else {
+                    GL11.glDisable(this.glCap);
+                }
             }
         }
     }

src/main/java/com/gtnewhorizons/angelica/glsm/states/ClientArrayState.java

@@ -1,93 +0,0 @@
-package com.gtnewhorizons.angelica.glsm.states;
-
-import java.nio.Buffer;
-import org.lwjgl.opengl.GL11;
-
-/**
- * Tracks OpenGL client array state (glVertexPointer, glColorPointer, etc.)
- * This state is NOT part of the server attribute stack (push/pop attrib),
- * but is needed for display list compilation to capture glDrawArrays calls.
- *
- * When a display list is compiled, glDrawArrays reads from the current
- * vertex/color arrays at compile time (not playback time). We need to track
- * this state globally so ImmediateModeRecorder can access it.
- */
-public class ClientArrayState {
-    // Vertex array state
-    private boolean vertexArrayEnabled = false;
-    private Buffer vertexPointer = null;
-    private int vertexPointerSize = 4;
-    private int vertexPointerType = GL11.GL_FLOAT;
-    private int vertexPointerStride = 0;
-
-    // Color array state
-    private boolean colorArrayEnabled = false;
-    private Buffer colorPointer = null;
-    private int colorPointerSize = 4;
-    private int colorPointerType = GL11.GL_FLOAT;
-    private int colorPointerStride = 0;
-
-    // Vertex array methods
-    public void setVertexPointer(int size, int type, int stride, Buffer pointer) {
-        this.vertexPointerSize = size;
-        this.vertexPointerType = type;
-        this.vertexPointerStride = stride;
-        this.vertexPointer = pointer;
-    }
-
-    public boolean isVertexArrayEnabled() {
-        return vertexArrayEnabled;
-    }
-
-    public void setVertexArrayEnabled(boolean enabled) {
-        this.vertexArrayEnabled = enabled;
-    }
-
-    public Buffer getVertexPointer() {
-        return vertexPointer;
-    }
-
-    public int getVertexPointerSize() {
-        return vertexPointerSize;
-    }
-
-    public int getVertexPointerType() {
-        return vertexPointerType;
-    }
-
-    public int getVertexPointerStride() {
-        return vertexPointerStride;
-    }
-
-    // Color array methods
-    public void setColorPointer(int size, int type, int stride, Buffer pointer) {
-        this.colorPointerSize = size;
-        this.colorPointerType = type;
-        this.colorPointerStride = stride;
-        this.colorPointer = pointer;
-    }
-
-    public boolean isColorArrayEnabled() {
-        return colorArrayEnabled;
-    }
-
-    public void setColorArrayEnabled(boolean enabled) {
-        this.colorArrayEnabled = enabled;
-    }
-
-    public Buffer getColorPointer() {
-        return colorPointer;
-    }
-
-    public int getColorPointerSize() {
-        return colorPointerSize;
-    }
-
-    public int getColorPointerType() {
-        return colorPointerType;
-    }
-
-    public int getColorPointerStride() {
-        return colorPointerStride;
-    }
-}

src/main/java/com/gtnewhorizons/angelica/glsm/states/ClipPlaneState.java

@@ -0,0 +1,34 @@
+package com.gtnewhorizons.angelica.glsm.states;
+
+import com.gtnewhorizons.angelica.glsm.GLStateManager;
+import org.joml.Matrix4f;
+import org.joml.Vector4f;
+
+import java.nio.FloatBuffer;
+
+/**
+ * Stores eye-space clip plane equations for core profile emulation.
+ */
+public class ClipPlaneState {
+    private final float[][] eyePlanes = new float[GLStateManager.MAX_CLIP_PLANES][4];
+
+    private static final Vector4f tempPlane = new Vector4f();
+    private static final Matrix4f tempInverse = new Matrix4f();
+
+    public void setPlane(int index, double a, double b, double c, double d, Matrix4f modelView) {
+        final float[] dest = eyePlanes[index];
+        modelView.invert(tempInverse);
+        tempPlane.set((float) a, (float) b, (float) c, (float) d);
+        tempInverse.transformTranspose(tempPlane);
+        dest[0] = tempPlane.x;
+        dest[1] = tempPlane.y;
+        dest[2] = tempPlane.z;
+        dest[3] = tempPlane.w;
+    }
+
+    /** Writes the 4-component eye-space plane equation into {@code buf} at its current position. */
+    public void putEyePlane(int index, FloatBuffer buf) {
+        final float[] p = eyePlanes[index];
+        buf.put(p[0]).put(p[1]).put(p[2]).put(p[3]);
+    }
+}

src/main/java/com/gtnewhorizons/angelica/glsm/states/DepthState.java

@@ -8,11 +8,13 @@ import org.lwjgl.opengl.GL11;
 public class DepthState implements ISettableState<DepthState> {
     protected boolean enabled = true;
     protected int func = GL11.GL_LESS;
+    protected double clearValue = 1.0;
 
     @Override
     public DepthState set(DepthState state) {
         this.enabled = state.enabled;
         this.func = state.func;
+        this.clearValue = state.clearValue;
         return this;
     }
 
@@ -20,7 +22,7 @@ public class DepthState implements ISettableState<DepthState> {
     public boolean sameAs(Object state) {
         if (this == state) return true;
         if (!(state instanceof DepthState depthState)) return false;
-        return enabled == depthState.enabled && func == depthState.func;
+        return enabled == depthState.enabled && func == depthState.func && Double.compare(clearValue, depthState.clearValue) == 0;
     }
     @Override
     public DepthState copy() {