Track render targets to avoid unnecessary composites

common/src/main/java/net/caffeinemc/mods/sodium/client/render/util/RenderTargetTracker.java

@@ -0,0 +1,35 @@
+package net.caffeinemc.mods.sodium.client.render.util;
+
+import com.mojang.blaze3d.pipeline.RenderTarget;
+import it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet;
+import it.unimi.dsi.fastutil.objects.ReferenceSet;
+
+public class RenderTargetTracker {
+    private static final ReferenceSet<RenderTarget> DIRTY_FRAMEBUFFERS = new ReferenceOpenHashSet<>();
+
+    private static RenderTarget ACTIVE_WRITE_TARGET;
+
+    public static void setActiveWriteTarget(RenderTarget rt) {
+        ACTIVE_WRITE_TARGET = rt;
+    }
+
+    public static void notifyActiveWriteTargetModified() {
+        RenderTarget rt = ACTIVE_WRITE_TARGET;
+
+        if (rt != null) {
+            markDirty(rt);
+        }
+    }
+
+    public static void markDirty(RenderTarget rt) {
+        DIRTY_FRAMEBUFFERS.add(rt);
+    }
+
+    public static boolean isDirty(RenderTarget rt) {
+        return DIRTY_FRAMEBUFFERS.contains(rt);
+    }
+
+    public static void markClean(RenderTarget rt) {
+        DIRTY_FRAMEBUFFERS.remove(rt);
+    }
+}

common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/render/compositing/LevelRendererMixin.java

@@ -0,0 +1,30 @@
+package net.caffeinemc.mods.sodium.mixin.features.render.compositing;
+
+import com.mojang.blaze3d.pipeline.RenderTarget;
+import net.caffeinemc.mods.sodium.client.render.util.RenderTargetTracker;
+import net.minecraft.client.renderer.LevelRenderer;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(LevelRenderer.class)
+public class LevelRendererMixin {
+    @Shadow
+    @Nullable
+    private RenderTarget entityTarget;
+
+    @Inject(method = "doEntityOutline", at = @At("HEAD"), cancellable = true)
+    private void preEntityOutlineComposite(CallbackInfo ci) {
+        RenderTarget entityTarget = this.entityTarget;
+
+        // If the entity render target hasn't been modified, don't try to composite it into the final image
+        if (entityTarget != null && !RenderTargetTracker.isDirty(entityTarget)) {
+            ci.cancel();
+        }
+
+        RenderTargetTracker.markClean(entityTarget);
+    }
+}

common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/render/compositing/RenderTargetMixin.java

@@ -2,6 +2,7 @@
 
 
 import com.mojang.blaze3d.pipeline.RenderTarget;
+import net.caffeinemc.mods.sodium.client.render.util.RenderTargetTracker;
 import org.lwjgl.opengl.GL32C;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
@@ -20,6 +21,11 @@ public class RenderTargetMixin {
     @Shadow
     public int height;
 
+    @Inject(method = "bindWrite", at = @At("HEAD"))
+    public void onBindWrite(boolean setViewport, CallbackInfo ci) {
+        RenderTargetTracker.setActiveWriteTarget((RenderTarget) (Object) this);
+    }
+
     /**
      * @author JellySquid
      * @reason Use fixed function hardware for framebuffer blits

common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/render/compositing/VertexBufferMixin.java

@@ -0,0 +1,17 @@
+package net.caffeinemc.mods.sodium.mixin.features.render.compositing;
+
+import com.mojang.blaze3d.vertex.VertexBuffer;
+import net.caffeinemc.mods.sodium.client.render.util.RenderTargetTracker;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(VertexBuffer.class)
+public class VertexBufferMixin {
+    @Inject(method = "draw", at = @At("RETURN"))
+    private void postDraw(CallbackInfo ci) {
+        // When any geometry is drawn, mark the framebuffer that it was rasterized to
+        RenderTargetTracker.notifyActiveWriteTargetModified();
+    }
+}

common/src/main/resources/sodium.mixins.json

@@ -41,7 +41,9 @@
     "features.options.render_layers.LeavesBlockMixin",
     "features.options.render_layers.ItemBlockRenderTypesMixin",
     "features.options.weather.LevelRendererMixin",
+    "features.render.compositing.LevelRendererMixin",
     "features.render.compositing.RenderTargetMixin",
+    "features.render.compositing.VertexBufferMixin",
     "features.render.entity.CubeMixin",
     "features.render.entity.ModelPartMixin",
     "features.render.entity.cull.EntityRendererMixin",