1 files changed, 116 insertions, 0 deletions
diff --git a/src/main/java/moe/nea/firmament/init/SectionBuilderRiser.java b/src/main/java/moe/nea/firmament/init/SectionBuilderRiser.java
new file mode 100644
index 0000000..2be11a6
--- /dev/null
+++ b/src/main/java/moe/nea/firmament/init/SectionBuilderRiser.java
@@ -0,0 +1,116 @@
+package moe.nea.firmament.init;
+
+import me.shedaniel.mm.api.ClassTinkerers;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.block.BlockState;
+import net.minecraft.client.render.block.BlockModels;
+import net.minecraft.client.render.block.BlockRenderManager;
+import net.minecraft.client.render.chunk.SectionBuilder;
+import net.minecraft.client.render.model.BakedModel;
+import net.minecraft.util.math.BlockPos;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.ClassNode;
+import org.objectweb.asm.tree.InsnList;
+import org.objectweb.asm.tree.LocalVariableNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+import org.objectweb.asm.tree.VarInsnNode;
+
+public class SectionBuilderRiser extends RiserUtils {
+
+    @IntermediaryName(SectionBuilder.class)
+    String SectionBuilder;
+    @IntermediaryName(BlockPos.class)
+    String BlockPos;
+    @IntermediaryName(BlockRenderManager.class)
+    String BlockRenderManager;
+    @IntermediaryName(BlockState.class)
+    String BlockState;
+    @IntermediaryName(BakedModel.class)
+    String BakedModel;
+    String CustomBlockTextures = "moe.nea.firmament.features.texturepack.CustomBlockTextures";
+
+    Type getModelDesc = Type.getMethodType(
+        getTypeForClassName(BlockRenderManager),
+        getTypeForClassName(BlockState)
+    );
+    String getModel = remapper.mapMethodName(
+        "intermediary",
+        Intermediary.<BlockRenderManager>className(),
+        Intermediary.methodName(net.minecraft.client.render.block.BlockRenderManager::getModel),
+        Type.getMethodDescriptor(
+            getTypeForClassName(Intermediary.<BakedModel>className()),
+            getTypeForClassName(Intermediary.<BlockState>className())
+        )
+    );
+
+    @Override
+    public void addTinkerers() {
+        if (FabricLoader.getInstance().isModLoaded("fabric-renderer-indigo"))
+            ClassTinkerers.addTransformation(SectionBuilder, this::handle, true);
+    }
+
+    private void handle(ClassNode classNode) {
+        for (MethodNode method : classNode.methods) {
+            if (method.name.endsWith("$fabric-renderer-indigo$hookChunkBuildTessellate") &&
+                method.name.startsWith("redirect$")) {
+                handleIndigo(method);
+                return;
+            }
+        }
+        new RuntimeException("Could not inject tesselation hook despite fabric renderer indigo being loaded").printStackTrace();
+    }
+
+    private void handleIndigo(MethodNode method) {
+        LocalVariableNode blockPosVar = null, blockStateVar = null;
+        for (LocalVariableNode localVariable : method.localVariables) {
+            if (Type.getType(localVariable.desc).equals(getTypeForClassName(BlockPos))) {
+                blockPosVar = localVariable;
+            }
+            if (Type.getType(localVariable.desc).equals(getTypeForClassName(BlockState))) {
+                blockStateVar = localVariable;
+            }
+        }
+        if (blockPosVar == null || blockStateVar == null) {
+            System.err.println("Firmament could inject into indigo: missing either block pos or blockstate");
+            return;
+        }
+        for (AbstractInsnNode instruction : method.instructions) {
+            if (instruction.getOpcode() != Opcodes.INVOKEVIRTUAL) continue;
+            var methodInsn = (MethodInsnNode) instruction;
+            if (!(methodInsn.name.equals(getModel) && Type.getObjectType(methodInsn.owner).equals(getTypeForClassName(BlockRenderManager))))
+                continue;
+            method.instructions.insertBefore(
+                methodInsn,
+                new MethodInsnNode(
+                    Opcodes.INVOKESTATIC,
+                    getTypeForClassName(CustomBlockTextures).getInternalName(),
+                    "enterFallbackCall",
+                    Type.getMethodDescriptor(Type.VOID_TYPE)
+                ));
+
+            var insnList = new InsnList();
+            insnList.add(new MethodInsnNode(
+                Opcodes.INVOKESTATIC,
+                getTypeForClassName(CustomBlockTextures).getInternalName(),
+                "exitFallbackCall",
+                Type.getMethodDescriptor(Type.VOID_TYPE)
+            ));
+            insnList.add(new VarInsnNode(Opcodes.ALOAD, blockPosVar.index));
+            insnList.add(new VarInsnNode(Opcodes.ALOAD, blockStateVar.index));
+            insnList.add(new MethodInsnNode(
+                Opcodes.INVOKESTATIC,
+                getTypeForClassName(CustomBlockTextures).getInternalName(),
+                "patchIndigo",
+                Type.getMethodDescriptor(getTypeForClassName(BakedModel),
+                                         getTypeForClassName(BakedModel),
+                                         getTypeForClassName(BlockPos),
+                                         getTypeForClassName(BlockState)),
+                false
+            ));
+            method.instructions.insert(methodInsn, insnList);
+        }
+    }
+}