From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Samsuik <kfian294ma4@gmail.com>
Date: Sun, 24 Dec 2023 16:54:07 +0000
Subject: [PATCH] Optimise check inside blocks and fluids


diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
index 2588180e543dc8ca2e41c15802b59c9b87df7ee6..f8e39e84a73754954be72bcd3e91de7cf0b0f6d7 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -1976,18 +1976,37 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
         BlockPos blockposition1 = BlockPos.containing(axisalignedbb.maxX - offset, axisalignedbb.maxY - offset, axisalignedbb.maxZ - offset);
         // Sakura end
 
-        if (this.level().hasChunksAt(blockposition, blockposition1)) {
+        // Sakura start - optimise check inside blocks
+        if (blockposition1.getY() >= level.getMinBuildHeight() || blockposition.getY() < level.getMaxBuildHeight()) {
             BlockPos.MutableBlockPos blockposition_mutableblockposition = new BlockPos.MutableBlockPos();
 
+            net.minecraft.world.level.chunk.ChunkAccess chunk = null;
+            int lastChunkX = Integer.MIN_VALUE;
+            int lastChunkZ = Integer.MIN_VALUE;
+
             for (int i = blockposition.getX(); i <= blockposition1.getX(); ++i) {
-                for (int j = blockposition.getY(); j <= blockposition1.getY(); ++j) {
-                    for (int k = blockposition.getZ(); k <= blockposition1.getZ(); ++k) {
+                final int chunkX = i >> 4;
+                for (int k = blockposition.getZ(); k <= blockposition1.getZ(); ++k) {
+                    final int chunkZ = k >> 4;
+
+                    if (lastChunkX != chunkX || lastChunkZ != chunkZ) {
+                        chunk = level.getChunkIfLoadedImmediately(chunkX, chunkZ);
+                        lastChunkX = chunkX;
+                        lastChunkZ = chunkZ;
+                    }
+
+                    if (chunk == null) {
+                        continue;
+                    }
+
+                    for (int j = blockposition.getY(); j <= blockposition1.getY(); ++j) {
                         if (!this.isAlive()) {
                             return;
                         }
 
                         blockposition_mutableblockposition.set(i, j, k);
-                        BlockState iblockdata = this.level().getBlockState(blockposition_mutableblockposition);
+                        BlockState iblockdata = chunk.getBlockState(blockposition_mutableblockposition);
+                        // Sakura end
 
                         try {
                             iblockdata.entityInside(this.level(), blockposition_mutableblockposition, this);
@@ -4771,7 +4790,7 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
     }
 
     public boolean updateFluidHeightAndDoFluidPushing(TagKey<Fluid> tag, double speed) {
-        if (this.touchingUnloadedChunk()) {
+        if (false) { // Sakura
             return false;
         } else {
             AABB axisalignedbb = this.getBoundingBox().deflate(0.001D);
@@ -4788,11 +4807,30 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
             int k1 = 0;
             BlockPos.MutableBlockPos blockposition_mutableblockposition = new BlockPos.MutableBlockPos();
 
+            // Sakura start
+            net.minecraft.world.level.chunk.ChunkAccess chunk = null;
+            int lastChunkX = Integer.MIN_VALUE;
+            int lastChunkZ = Integer.MIN_VALUE;
+
             for (int l1 = i; l1 < j; ++l1) {
-                for (int i2 = k; i2 < l; ++i2) {
-                    for (int j2 = i1; j2 < j1; ++j2) {
+                final int chunkX = l1 >> 4;
+                for (int j2 = i1; j2 < j1; ++j2) {
+                    final int chunkZ = j2 >> 4;
+
+                    if (chunkX != lastChunkX || chunkZ != lastChunkZ) {
+                        chunk = level.getChunkIfLoadedImmediately(chunkX, chunkZ);
+                        lastChunkX = chunkX;
+                        lastChunkZ = chunkZ;
+                    }
+
+                    if (chunk == null) {
+                        return false;
+                    }
+
+                    for (int i2 = k; i2 < l; ++i2) {
                         blockposition_mutableblockposition.set(l1, i2, j2);
-                        FluidState fluid = this.level().getFluidState(blockposition_mutableblockposition);
+                        FluidState fluid = chunk.getFluidState(blockposition_mutableblockposition);
+                        // Sakura end
 
                         if (fluid.is(tag)) {
                             double d2 = (double) ((float) i2 + fluid.getHeight(this.level(), blockposition_mutableblockposition));