fix(microblock): prevent microblocks becoming blood rune slabs (#47)

src/main/scala/codechicken/microblock/DefaultContent.scala

@@ -54,5 +54,7 @@ object DefaultContent {
     registerMaterial(new GrassMicroMaterial, materialKey(grass))
     MicroMaterialRegistry.remapName(oldKey(mycelium), materialKey(mycelium))
     registerMaterial(new TopMicroMaterial(mycelium), materialKey(mycelium))
+
+    registerMaterial(MissingMicroMaterial, MissingMicroMaterial.key)
   }
 }

src/main/scala/codechicken/microblock/ItemMicroPart.scala

@@ -133,15 +133,18 @@ object ItemMicroPart {
     if (!stack.getTagCompound.hasKey("mat"))
       return null
 
-    return MicroMaterialRegistry.getMaterial(
+    MicroMaterialRegistry.getMaterial(
       stack.getTagCompound.getString("mat")
-    )
+    ) match {
+      case null => MissingMicroMaterial
+      case mat  => mat
+    }
   }
 
   def getMaterialID(stack: ItemStack): Int = {
     checkTagCompound(stack)
     if (!stack.getTagCompound.hasKey("mat"))
-      return 0
+      return MicroMaterialRegistry.getMissingId
 
     return MicroMaterialRegistry.materialID(
       stack.getTagCompound.getString("mat")

src/main/scala/codechicken/microblock/MicroMaterialRegistry.scala

@@ -114,6 +114,7 @@ object MicroMaterialRegistry {
   private var maxCuttingStrength: Int = _
 
   private val remap = HashMap[String, String]()
+  private var missingId: Int = 0
 
   /** Register a micro material with unique identifier name
     */
@@ -162,8 +163,17 @@ object MicroMaterialRegistry {
     nameMap.clear()
     for (i <- 0 until idMap.length)
       nameMap.put(idMap(i)._1, i)
+    missingId = nameMap.getOrElse(
+      MissingMicroMaterial.key,
+      throw new IllegalStateException(
+        "MissingMicroMaterial is not registered; the placeholder must never " +
+          "fall back to id 0."
+      )
+    )
   }
 
+  def getMissingId = missingId
+
   private[microblock] def calcMaxCuttingStrength() {
     val it = Item.itemRegistry.iterator.asInstanceOf[JIterator[Item]]
     maxCuttingStrength = it.flatMap {
@@ -216,7 +226,7 @@ object MicroMaterialRegistry {
       case Some(v) => v
       case None =>
         logger.error("Missing mapping for part with ID: " + name)
-        0
+        missingId
     }
 
   def getMaterial(name: String) =

src/main/scala/codechicken/microblock/MissingMicroMaterial.scala

@@ -0,0 +1,55 @@
+package codechicken.microblock
+
+import codechicken.lib.render.uv.IconTransformation
+import codechicken.lib.vec.{Cuboid6, Vector3}
+import codechicken.microblock.MicroMaterialRegistry.IMicroMaterial
+import codechicken.microblock.handler.MicroblockProxy
+import cpw.mods.fml.relauncher.{Side, SideOnly}
+import net.minecraft.block.Block
+import net.minecraft.block.Block.SoundType
+import net.minecraft.entity.Entity
+import net.minecraft.entity.player.EntityPlayer
+import net.minecraft.init.Blocks
+import net.minecraft.item.ItemStack
+import net.minecraft.util.IIcon
+
+/** Stand-in for a material whose name could not be resolved at load time.
+  * Renders the vanilla missing texture (magenta/black checkerboard) and behaves
+  * inertly. Resolving an unknown name to this placeholder keeps microblocks
+  * from silently becoming material id 0 (Blood Rune in GTNH).
+  */
+object MissingMicroMaterial extends IMicroMaterial {
+  val key = "forgemicroblock:missing"
+
+  @SideOnly(Side.CLIENT)
+  private var icon: IIcon = _
+
+  @SideOnly(Side.CLIENT)
+  override def loadIcons(): Unit = {
+    icon = MicroblockProxy.renderBlocks.getIconSafe(null)
+  }
+
+  @SideOnly(Side.CLIENT)
+  override def getBreakingIcon(side: Int): IIcon = icon
+
+  @SideOnly(Side.CLIENT)
+  override def renderMicroFace(
+      pos: Vector3,
+      pass: Int,
+      bounds: Cuboid6
+  ): Unit = {
+    MaterialRenderHelper
+      .start(pos, pass, new IconTransformation(icon))
+      .lighting()
+      .render()
+  }
+
+  override def isTransparent: Boolean = false
+  override def getLightValue: Int = 0
+  override def getStrength(player: EntityPlayer): Float = 1f
+  override def getLocalizedName: String = "Missing Material"
+  override def getItem: ItemStack = new ItemStack(Blocks.stone)
+  override def getCutterStrength: Int = 0
+  override def getSound: SoundType = Block.soundTypeStone
+  override def explosionResistance(entity: Entity): Float = 6f
+}

src/main/scala/codechicken/microblock/handler/packethandlers.scala

@@ -26,7 +26,14 @@ object MicroblockCPH extends MicroblockPH with IClientPacketHandler {
       netHandler: INetHandlerPlayClient
   ) {
     packet.getType match {
-      case 1 => handleMaterialRegistration(packet, netHandler)
+      // In singleplayer the integrated server and this client share the one
+      // static registry, so the id-map packet is redundant. Skipping it avoids
+      // rebuilding (clearing) the shared maps on the netty thread while the
+      // server thread reads them - the race that turned microblocks into Blood
+      // Rune slabs.
+      case 1 =>
+        if (!mc.isSingleplayer)
+          handleMaterialRegistration(packet, netHandler)
     }
   }