Fix VAOManager desync & Post-splash gap

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

@@ -313,7 +313,7 @@ public class GLStateManager {
     private static volatile boolean splashComplete = false;
     @Getter @Setter private static Thread drawableGLHolder = MainThread;
     // Reference to DrawableGL (main display context) - works with both FML and BLS splash
-    @Setter private static Drawable drawableGL = null;
+    @Setter private static volatile Drawable drawableGL = null;
 
     private static final ReentrantLock DRAW_LOCK = new ReentrantLock();
 
@@ -3341,10 +3341,9 @@ public class GLStateManager {
         }
         CurrentThread = Thread.currentThread();
 
-        if (splashComplete) return;
-
         if (drawableGL == null) {
-            // Lazy-capture DrawableGL reference (Display.getDrawable()) on first opportunity
+            // Lazy-capture DrawableGL reference (Display.getDrawable()) on first opportunity.
+            // markSplashComplete clears it, so this re-runs after the splash too.
             try {
                 if (drawable == Display.getDrawable()) {
                     drawableGL = drawable;
@@ -3356,19 +3355,27 @@ public class GLStateManager {
             }
         }
 
-        if (drawableGL != null && drawable == drawableGL) {
+        final boolean isDrawableGL = drawableGL != null && drawable == drawableGL;
+        if (isDrawableGL) {
             exitWorkerContext();
-            // Switching TO DrawableGL - enable caching for this thread
-            drawableGLHolder = CurrentThread;
         } else {
             enterWorkerContext();
-            if (drawableGLHolder == CurrentThread) {
+        }
+
+        if (!splashComplete) {
+            if (isDrawableGL) {
+                // Switching TO DrawableGL - enable caching for this thread
+                drawableGLHolder = CurrentThread;
+            } else if (drawableGLHolder == CurrentThread) {
                 // This thread held DrawableGL but is switching AWAY - disable caching
                 drawableGLHolder = null;
             }
         }
 
-        if (CurrentThread != MainThread && !autoVaoBound.get()) {
+        // Worker contexts have no VAO of their own; core profile rejects draws without one.
+        // DrawableGL already carries defaultVAO once initialize() has run, but during the splash
+        // it may not have, so keep binding there too.
+        if (CurrentThread != MainThread && !autoVaoBound.get() && (!isDrawableGL || !splashComplete)) {
             autoVaoBound.set(Boolean.TRUE);
             glBindVertexArray(glGenVertexArrays());
         }
@@ -6111,9 +6118,9 @@ public class GLStateManager {
         }
         final boolean locked = acquireDrawLock();
         try {
+            VAOManager.onBindVertexArrayPre(array);
             if (glCtx.boundVAO != array) {
                 glCtx.boundVAO = array;
-                VAOManager.onBindVertexArrayPre(array);
                 RENDER_BACKEND.bindVertexArray(array);
             }
         } finally {

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

@@ -19,6 +19,9 @@ public final class VAOManager {
     static final Int2ObjectOpenHashMap<VAOData> eboOwners = new Int2ObjectOpenHashMap<>();
 
     private static VAOData current = null;
+    // Which VAO name `current` reflects. Per-context boundVAO caching can skip a bind that is a
+    // no-op for that context but still a switch for this global tracker, so it needs its own id.
+    private static int currentVaoId = -1;
     private static int currentVertexFlags = 0;
     private static Attrib[] currentAttribs = null;
     public static int boundEBO = 0;
@@ -29,6 +32,7 @@ public final class VAOManager {
     public static void init(int defaultVAO) {
         final VAOData data = new VAOData();
         current = data;
+        currentVaoId = defaultVAO;
         currentAttribs = data.attribs;
         vaoMap.put(defaultVAO, data);
     }
@@ -38,6 +42,9 @@ public final class VAOManager {
     }
 
     public static void onBindVertexArrayPre(int vaoId) {
+        if (vaoId == currentVaoId) return;
+        currentVaoId = vaoId;
+
         // Save old VAO data
         if (current != null) {
             current.vertexFlags = currentVertexFlags;
@@ -66,7 +73,10 @@ public final class VAOManager {
         final VAOData data = vaoMap.remove(vaoId);
         if (data == null) return;
         removeEboOwner(data.ebo, data);
-        if (data == current) current = null;
+        if (data == current) {
+            current = null;
+            currentVaoId = -1;
+        }
     }
 
     public static void onDeleteBuffer(int buffer) {