Fix chunk flicker with Sodium 0.3.0, release version 2.0.4

They removed the buffering behavior of their ChunkStatusListener which was
present in snapshot versions of 0.3.0, so we need to take care of that manually
again.

CHANGELOG.md

@@ -1,3 +1,6 @@
+### 2.0.4
+- Fix chunk flicker with Sodium 0.3.0 (broke shortly before release)
+
 ### 2.0.3
 - Update to Minecraft 1.17.1
 

gradle.properties

@@ -7,7 +7,7 @@ org.gradle.jvmargs=-Xmx2G
 	loaderVersion=0.11.6
 
 # Mod Properties
-	modVersion = 2.0.3
+	modVersion = 2.0.4
 	mavenGroup = de.johni0702.minecraft
 	archivesBaseName = bobby
 	github.owner = johni0702

src/main/java/de/johni0702/minecraft/bobby/ext/ClientChunkManagerExt.java

@@ -1,9 +1,27 @@
 package de.johni0702.minecraft.bobby.ext;
 
 import de.johni0702.minecraft.bobby.FakeChunkManager;
+import me.jellysquid.mods.sodium.client.world.ChunkStatusListener;
 
 public interface ClientChunkManagerExt {
     FakeChunkManager bobby_getFakeChunkManager();
     void bobby_onFakeChunkAdded(int x, int z);
     void bobby_onFakeChunkRemoved(int x, int z);
+
+    /**
+     * Mark Sodium's {@link ChunkStatusListener} as paused.
+     * This effectively delays all unload notifications until un-paused and most importantly removes redundant (as in
+     * unload followed by a load) ones. Otherwise Sodium will unload the geometry and the chunk will be missing until
+     * it is rebuilt.
+     *
+     * Has no effect on the vanilla renderer because it polls chunks every frame and gets no intermediate state.
+     *
+     * This method is idempotent.
+     */
+    void bobby_pauseChunkStatusListener();
+
+    /**
+     * Resumes Sodium's {@link ChunkStatusListener}, forwarding all updates which are still applicable.
+     */
+    void bobby_resumeChunkStatusListener();
 }

src/main/java/de/johni0702/minecraft/bobby/mixin/ClientChunkManagerMixin.java

@@ -84,11 +84,18 @@ private void bobbyUnloadFakeChunk(int x, int z, BiomeArray biomes, PacketByteBuf
             return;
         }
 
+        bobby_pauseChunkStatusListener();
+
         // This needs to be called unconditionally because even if there is no chunk loaded at the moment,
         // we might already have one queued which we need to cancel as otherwise it will overwrite the real one later.
         bobbyChunkManager.unload(x, z, true);
     }
 
+    @Inject(method = "loadChunkFromPacket", at = @At("RETURN"))
+    private void bobbyPostLoadRealChunk(CallbackInfoReturnable<WorldChunk> cir) {
+        bobby_resumeChunkStatusListener();
+    }
+
     @Unique
     private void saveRealChunk(long chunkPos) {
         int chunkX = ChunkPos.getPackedX(chunkPos);
@@ -105,6 +112,8 @@ private void saveRealChunk(long chunkPos) {
 
         if (bobbyChunkManager.shouldBeLoaded(chunkX, chunkZ)) {
             bobbyChunkReplacements.add(Pair.of(chunkPos, tag));
+
+            bobby_pauseChunkStatusListener();
         }
     }
 
@@ -117,6 +126,8 @@ private void substituteFakeChunksForUnloadedRealOnes() {
             bobbyChunkManager.load(chunkX, chunkZ, entry.getValue(), bobbyChunkManager.getStorage());
         }
         bobbyChunkReplacements.clear();
+
+        bobby_resumeChunkStatusListener();
     }
 
     @Inject(method = "unload", at = @At("HEAD"))
@@ -173,4 +184,14 @@ public void bobby_onFakeChunkAdded(int x, int z) {
     public void bobby_onFakeChunkRemoved(int x, int z) {
         // Vanilla polls for chunks each frame, this is only of interest for Sodium (see SodiumChunkManagerMixin)
     }
+
+    @Override
+    public void bobby_pauseChunkStatusListener() {
+        // Vanilla polls for chunks each frame, this is only of interest for Sodium (see SodiumChunkManagerMixin)
+    }
+
+    @Override
+    public void bobby_resumeChunkStatusListener() {
+        // Vanilla polls for chunks each frame, this is only of interest for Sodium (see SodiumChunkManagerMixin)
+    }
 }

src/main/java/de/johni0702/minecraft/bobby/mixin/sodium/SodiumChunkManagerMixin.java

@@ -1,11 +1,13 @@
 package de.johni0702.minecraft.bobby.mixin.sodium;
 
 import de.johni0702.minecraft.bobby.ext.ClientChunkManagerExt;
+import de.johni0702.minecraft.bobby.sodium.BufferedChunkStatusListener;
 import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
 import me.jellysquid.mods.sodium.client.world.ChunkStatusListener;
 import net.minecraft.client.world.ClientChunkManager;
 import net.minecraft.util.math.ChunkPos;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
 
 @Mixin(value = ClientChunkManager.class, priority = 1010) // higher than our normal one
 public abstract class SodiumChunkManagerMixin implements ClientChunkManagerExt {
@@ -14,6 +16,9 @@ public abstract class SodiumChunkManagerMixin implements ClientChunkManagerExt {
     /* Shadows the one in Sodium's Mixin */
     private ChunkStatusListener listener;
 
+    @Unique
+    private BufferedChunkStatusListener bufferedListener;
+
     @Override
     public void bobby_onFakeChunkAdded(int x, int z) {
         if (this.listener != null && this.loadedChunks.add(ChunkPos.toLong(x, z))) {
@@ -27,4 +32,27 @@ public void bobby_onFakeChunkRemoved(int x, int z) {
             this.listener.onChunkRemoved(x, z);
         }
     }
+
+    @Override
+    public void bobby_pauseChunkStatusListener() {
+        if (this.listener == this.bufferedListener) {
+            return;
+        }
+
+        if (this.bufferedListener == null || this.bufferedListener.delegate != this.listener) {
+            this.bufferedListener = new BufferedChunkStatusListener(this.listener);
+        }
+
+        this.listener = this.bufferedListener;
+    }
+
+    @Override
+    public void bobby_resumeChunkStatusListener() {
+        if (this.listener != this.bufferedListener) {
+            return;
+        }
+
+        this.bufferedListener.flush();
+        this.listener = this.bufferedListener.delegate;
+    }
 }

src/main/java/de/johni0702/minecraft/bobby/sodium/BufferedChunkStatusListener.java

@@ -0,0 +1,34 @@
+package de.johni0702.minecraft.bobby.sodium;
+
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
+import it.unimi.dsi.fastutil.longs.LongSet;
+import me.jellysquid.mods.sodium.client.world.ChunkStatusListener;
+import net.minecraft.util.math.ChunkPos;
+
+public class BufferedChunkStatusListener implements ChunkStatusListener {
+    public final ChunkStatusListener delegate;
+    private final LongSet unloaded = new LongOpenHashSet();
+
+    public BufferedChunkStatusListener(ChunkStatusListener delegate) {
+        this.delegate = delegate;
+    }
+
+    @Override
+    public void onChunkAdded(int x, int z) {
+        if (!this.unloaded.remove(ChunkPos.toLong(x, z))) {
+            this.delegate.onChunkAdded(x, z);
+        }
+    }
+
+    @Override
+    public void onChunkRemoved(int x, int z) {
+        this.unloaded.add(ChunkPos.toLong(x, z));
+    }
+
+    public void flush() {
+        for (long pos : this.unloaded) {
+            this.delegate.onChunkRemoved(ChunkPos.getPackedX(pos), ChunkPos.getPackedZ(pos));
+        }
+        this.unloaded.clear();
+    }
+}