From d6b0f3f9978799b26a3ebca1a91ebc110a6b894a Mon Sep 17 00:00:00 2001
From: makamys <makamys@outlook.com>
Date: Tue, 21 Jun 2022 04:46:43 +0200
Subject: Recycle MeshQuad objects

Reduces client thread's RAM allocation rate from ~80 MB/s to ~20 MB/s.
---
 .../java/makamys/neodymium/renderer/ChunkMesh.java | 10 ++++--
 .../java/makamys/neodymium/renderer/MeshQuad.java  | 34 +++++++++++++++++++-
 .../java/makamys/neodymium/util/RecyclingList.java | 37 ++++++++++++++++++++++
 3 files changed, 77 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/makamys/neodymium/util/RecyclingList.java

diff --git a/src/main/java/makamys/neodymium/renderer/ChunkMesh.java b/src/main/java/makamys/neodymium/renderer/ChunkMesh.java
index abe9a2d..ff6e6ba 100644
--- a/src/main/java/makamys/neodymium/renderer/ChunkMesh.java
+++ b/src/main/java/makamys/neodymium/renderer/ChunkMesh.java
@@ -19,6 +19,7 @@ import makamys.neodymium.MixinConfigPlugin;
 import makamys.neodymium.Neodymium;
 import makamys.neodymium.ducks.IWorldRenderer;
 import makamys.neodymium.util.BufferWriter;
+import makamys.neodymium.util.RecyclingList;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.client.renderer.WorldRenderer;
@@ -40,6 +41,8 @@ public class ChunkMesh extends Mesh {
     public static int usedRAM = 0;
     public static int instances = 0;
     
+    private static RecyclingList<MeshQuad> quadBuf = new RecyclingList<>(() -> new MeshQuad());
+    
     public ChunkMesh(int x, int y, int z, Flags flags, int quadCount, ByteBuffer buffer, int pass) {
         this.x = x;
         this.y = y;
@@ -86,13 +89,14 @@ public class ChunkMesh extends Mesh {
         
         ChunkMesh.Flags flags = new ChunkMesh.Flags(t.hasTexture, t.hasBrightness, t.hasColor, t.hasNormals);
         
-        List<MeshQuad> quads = new ArrayList<>();
+        quadBuf.reset();
         
         for(int quadI = 0; quadI < t.vertexCount / 4; quadI++) {
-            MeshQuad quad = new MeshQuad(t.rawBuffer, quadI * 32, flags, tessellatorXOffset, tessellatorYOffset, tessellatorZOffset);
-            quads.add(quad);
+            quadBuf.next().setState(t.rawBuffer, quadI * 32, flags, tessellatorXOffset, tessellatorYOffset, tessellatorZOffset);
         }
         
+        List<MeshQuad> quads = quadBuf.getAsList();
+        
         if(Config.simplifyChunkMeshes) {
             ArrayList<ArrayList<MeshQuad>> quadsByPlaneDir = new ArrayList<>(); // XY, XZ, YZ
             for(int i = 0; i < 3; i++) {
diff --git a/src/main/java/makamys/neodymium/renderer/MeshQuad.java b/src/main/java/makamys/neodymium/renderer/MeshQuad.java
index 2024efd..1ff4173 100644
--- a/src/main/java/makamys/neodymium/renderer/MeshQuad.java
+++ b/src/main/java/makamys/neodymium/renderer/MeshQuad.java
@@ -96,7 +96,9 @@ public class MeshQuad {
         }
     }
     
-    public MeshQuad(int[] rawBuffer, int offset, ChunkMesh.Flags flags, int offsetX, int offsetY, int offsetZ) {
+    public void setState(int[] rawBuffer, int offset, ChunkMesh.Flags flags, int offsetX, int offsetY, int offsetZ) {
+        resetState();
+        
         read(rawBuffer, offset, offsetX, offsetY, offsetZ);
         
         uDirectionIs01 = us[0] != us[1];
@@ -110,6 +112,36 @@ public class MeshQuad {
         normal = QuadNormal.fromVector(vectorC);
     }
     
+    private void resetState() {
+        Arrays.fill(xs, 0);
+        Arrays.fill(ys, 0);
+        Arrays.fill(zs, 0);
+        Arrays.fill(us, 0);
+        Arrays.fill(vs, 0);
+        Arrays.fill(bs, 0);
+        Arrays.fill(cs, 0);
+        
+        minX = Float.POSITIVE_INFINITY;
+        minY = Float.POSITIVE_INFINITY;
+        minZ = Float.POSITIVE_INFINITY;
+        maxX = Float.NEGATIVE_INFINITY;
+        maxY = Float.NEGATIVE_INFINITY;
+        maxZ = Float.NEGATIVE_INFINITY;
+        
+        deleted = noMerge = false;
+        normal = null;
+        offset = 0;
+        flags = null;
+        uDirectionIs01 = false;
+        Arrays.fill(quadCountByDirection, 1);
+        Arrays.fill(totalMergeCountByPlane, 0);
+        mergeReference = null;
+    }
+    
+    public MeshQuad() {
+        
+    }
+    
     public void writeToBuffer(BufferWriter out) throws IOException {
         for(int vertexI = 0; vertexI < 4; vertexI++) {
             int vi = vertexI;
diff --git a/src/main/java/makamys/neodymium/util/RecyclingList.java b/src/main/java/makamys/neodymium/util/RecyclingList.java
new file mode 100644
index 0000000..ea240bb
--- /dev/null
+++ b/src/main/java/makamys/neodymium/util/RecyclingList.java
@@ -0,0 +1,37 @@
+package makamys.neodymium.util;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Supplier;
+
+public class RecyclingList<T> {
+    
+    private Supplier<T> constructor;
+    
+    int nextIndex;
+    private List<T> list;
+    
+    public RecyclingList(Supplier<T> constructor) {
+        this.constructor = constructor;
+        this.list = new ArrayList<T>();
+    }
+    
+    public T get(int i) {
+        while(list.size() <= i) {
+            list.add(constructor.get());
+        }
+        return list.get(i);
+    }
+    
+    public T next() {
+        return get(nextIndex++);
+    }
+    
+    public void reset() {
+        nextIndex = 0;
+    }
+
+    public List<T> getAsList() {
+        return list.subList(0, nextIndex);
+    }
+}
-- 
cgit