From 7d0c8b1e2f76223e9debcc7a6789bf0c53e0c43a Mon Sep 17 00:00:00 2001
From: douira <douira100@gmail.com>
Date: Wed, 20 Nov 2024 17:58:56 +0100
Subject: [PATCH] avoids rebuilding the render lists and doing a graph search
 more often than necessary by checking if the section actually changed in a
 way that's relevant to the graph search

---
 .../client/render/chunk/RenderSection.java    | 24 +++++++++++++++----
 .../render/chunk/RenderSectionManager.java    | 16 +++++++------
 2 files changed, 28 insertions(+), 12 deletions(-)

diff --git a/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSection.java b/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSection.java
index 0103850155..9c8e9f8d28 100644
--- a/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSection.java
+++ b/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSection.java
@@ -139,30 +139,44 @@ public void delete() {
         this.disposed = true;
     }
 
-    public void setInfo(@Nullable BuiltSectionInfo info) {
+    public boolean setInfo(@Nullable BuiltSectionInfo info) {
         if (info != null) {
-            this.setRenderState(info);
+            return this.setRenderState(info);
         } else {
-            this.clearRenderState();
+            return this.clearRenderState();
         }
     }
 
-    private void setRenderState(@NotNull BuiltSectionInfo info) {
+    private boolean setRenderState(@NotNull BuiltSectionInfo info) {
+        var prevBuilt = this.built;
+        var prevFlags = this.flags;
+        var prevVisibilityData = this.visibilityData;
+
         this.built = true;
         this.flags = info.flags;
         this.visibilityData = info.visibilityData;
+
         this.globalBlockEntities = info.globalBlockEntities;
         this.culledBlockEntities = info.culledBlockEntities;
         this.animatedSprites = info.animatedSprites;
+
+        // the section is marked as having received graph-relevant changes if it's build state, flags, or connectedness has changed.
+        // the entities and sprites don't need to be checked since whether they exist is encoded in the flags.
+        return !prevBuilt || prevFlags != this.flags || prevVisibilityData != this.visibilityData;
     }
 
-    private void clearRenderState() {
+    private boolean clearRenderState() {
+        var wasBuilt = this.built;
+
         this.built = false;
         this.flags = RenderSectionFlags.NONE;
         this.visibilityData = VisibilityEncoding.NULL;
         this.globalBlockEntities = null;
         this.culledBlockEntities = null;
         this.animatedSprites = null;
+
+        // changes to data if it moves from built to not built don't matter, so only build state changes matter
+        return wasBuilt;
     }
 
     /**
diff --git a/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSectionManager.java b/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSectionManager.java
index 516255ecac..8cbfe8ed70 100644
--- a/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSectionManager.java
+++ b/common/src/main/java/net/caffeinemc/mods/sodium/client/render/chunk/RenderSectionManager.java
@@ -209,6 +209,7 @@ public void onSectionAdded(int x, int y, int z) {
 
         this.connectNeighborNodes(renderSection);
 
+        // force update to schedule build task
         this.needsGraphUpdate = true;
     }
 
@@ -235,6 +236,7 @@ public void onSectionRemoved(int x, int y, int z) {
 
         section.delete();
 
+        // force update to remove section from render lists
         this.needsGraphUpdate = true;
     }
 
@@ -301,7 +303,7 @@ public void uploadChunks() {
         // (sort results never change the graph)
         // generally there's no sort results without a camera movement, which would also trigger
         // a graph update, but it can sometimes happen because of async task execution
-        this.needsGraphUpdate = this.needsGraphUpdate || this.processChunkBuildResults(results);
+        this.needsGraphUpdate |= this.processChunkBuildResults(results);
 
         for (var result : results) {
             result.destroy();
@@ -317,8 +319,7 @@ private boolean processChunkBuildResults(ArrayList<BuilderTaskOutput> results) {
         for (var result : filtered) {
             TranslucentData oldData = result.render.getTranslucentData();
             if (result instanceof ChunkBuildOutput chunkBuildOutput) {
-                this.updateSectionInfo(result.render, chunkBuildOutput.info);
-                touchedSectionInfo = true;
+                touchedSectionInfo |= this.updateSectionInfo(result.render, chunkBuildOutput.info);
 
                 if (chunkBuildOutput.translucentData != null) {
                     this.sortTriggering.integrateTranslucentData(oldData, chunkBuildOutput.translucentData, this.cameraPosition, this::scheduleSort);
@@ -346,13 +347,13 @@ private boolean processChunkBuildResults(ArrayList<BuilderTaskOutput> results) {
         return touchedSectionInfo;
     }
 
-    private void updateSectionInfo(RenderSection render, BuiltSectionInfo info) {
-        render.setInfo(info);
+    private boolean updateSectionInfo(RenderSection render, BuiltSectionInfo info) {
+        var infoChanged = render.setInfo(info);
 
         if (info == null || ArrayUtils.isEmpty(info.globalBlockEntities)) {
-            this.sectionsWithGlobalEntities.remove(render);
+            return this.sectionsWithGlobalEntities.remove(render) || infoChanged;
         } else {
-            this.sectionsWithGlobalEntities.add(render);
+            return this.sectionsWithGlobalEntities.add(render) || infoChanged;
         }
     }
 
@@ -609,6 +610,7 @@ public void scheduleRebuild(int x, int y, int z, boolean important) {
             if (pendingUpdate != null) {
                 section.setPendingUpdate(pendingUpdate);
 
+                // force update to schedule rebuild task on this section
                 this.needsGraphUpdate = true;
             }
         }