Multi-layer rendering support

src/main/kotlin/mods/betterfoliage/render/pipeline/RenderCtxBase.kt

@@ -12,9 +12,10 @@ import mods.betterfoliage.util.Int3
 import mods.betterfoliage.util.plus
 import net.minecraft.block.Block
 import net.minecraft.client.Minecraft
+import net.minecraft.client.renderer.BlockRendererDispatcher
+import net.minecraft.client.renderer.chunk.ChunkRenderCache
 import net.minecraft.util.Direction
 import net.minecraft.util.math.BlockPos
-import net.minecraft.world.IBlockDisplayReader
 import net.minecraftforge.client.model.data.IModelData
 import java.util.Random
 
@@ -25,17 +26,19 @@ import java.util.Random
  * push-based partial rendering pipeline for [SpecialRenderModel] instances.
  */
 abstract class RenderCtxBase(
-    world: IBlockDisplayReader,
-    pos: BlockPos,
+    blockCtx: BlockCtx,
     val matrixStack: MatrixStack,
     var checkSides: Boolean,
     val random: Random,
-    val modelData: IModelData
-) : BlockCtx by BasicBlockCtx(world, pos) {
-
-    abstract fun renderQuad(quad: HalfBakedQuad)
+    val modelData: IModelData,
+) : BlockCtx by blockCtx {
 
     var hasRendered = false
+    var modelRenderData: Any? = null
+    inline fun <reified T> withRenderData(renderFunc: (T)->Boolean) = (modelRenderData as? T?).let {
+        if (it == null) false else renderFunc(it)
+    }
+
     val blockModelShapes = Minecraft.getInstance().blockRenderer.blockModelShaper
     var vertexLighter: VanillaVertexLighter = VanillaFullBlockLighting
     protected val lightingData = RenderCtxBase.lightingData.get().apply {
@@ -43,6 +46,8 @@ abstract class RenderCtxBase(
         blockColors = Minecraft.getInstance().blockColors
     }
 
+    abstract fun renderQuad(quad: HalfBakedQuad)
+
     inline fun Direction?.shouldRender() = this == null || !checkSides || Block.shouldRenderFace(state, world, pos, this)
 
     fun renderQuads(quads: Iterable<HalfBakedQuad>) {
@@ -61,6 +66,17 @@ abstract class RenderCtxBase(
     }
 
     companion object {
+        @JvmStatic
+        fun reset(chunkRenderCache: ChunkRenderCache, blockRendererDispatcher: BlockRendererDispatcher, pos: BlockPos, random: Random) {
+            // prepare render data
+            val blockCtx = BasicBlockCtx(chunkRenderCache, pos)
+            val model = blockRendererDispatcher.getBlockModel(blockCtx.state)
+            random.setSeed(blockCtx.seed)
+            val data = if (model is SpecialRenderModel) model.prepare(blockCtx, random) else Unit
+            specialRenderData.set(data)
+        }
+
         val lightingData = ThreadLocal.withInitial { VanillaQuadLighting() }
+        val specialRenderData = ThreadLocal<Any?>()
     }
 }