From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: lukas81298 <lukas81298@gommehd.net>
Date: Fri, 22 Jan 2021 21:50:18 +0100
Subject: [PATCH] optimize dirt and snow spreading

Feature patch

diff --git a/src/main/java/net/minecraft/world/level/block/SpreadingSnowyDirtBlock.java b/src/main/java/net/minecraft/world/level/block/SpreadingSnowyDirtBlock.java
index 30047cbef0ef54ad326e71761cba64887624d493..4e38d2e0ce156b4edbef67c82c845ceeebbbcd59 100644
--- a/src/main/java/net/minecraft/world/level/block/SpreadingSnowyDirtBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/SpreadingSnowyDirtBlock.java
@@ -18,8 +18,13 @@ public abstract class SpreadingSnowyDirtBlock extends SnowyDirtBlock {
     }
 
     private static boolean canBeGrass(BlockState state, LevelReader world, BlockPos pos) {
+    // Paper start - Perf: optimize dirt and snow spreading
+        return canBeGrass(world.getChunk(pos), state, world, pos);
+    }
+    private static boolean canBeGrass(net.minecraft.world.level.chunk.ChunkAccess chunk, BlockState state, LevelReader world, BlockPos pos) {
+    // Paper end - Perf: optimize dirt and snow spreading
         BlockPos blockposition1 = pos.above();
-        BlockState iblockdata1 = world.getBlockState(blockposition1);
+        BlockState iblockdata1 = chunk.getBlockState(blockposition1); // Paper - Perf: optimize dirt and snow spreading
 
         if (iblockdata1.is(Blocks.SNOW) && (Integer) iblockdata1.getValue(SnowLayerBlock.LAYERS) == 1) {
             return true;
@@ -36,15 +41,27 @@ public abstract class SpreadingSnowyDirtBlock extends SnowyDirtBlock {
     protected abstract MapCodec<? extends SpreadingSnowyDirtBlock> codec();
 
     private static boolean canPropagate(BlockState state, LevelReader world, BlockPos pos) {
+    // Paper start - Perf: optimize dirt and snow spreading
+        return canPropagate(world.getChunk(pos), state, world, pos);
+    }
+
+    private static boolean canPropagate(net.minecraft.world.level.chunk.ChunkAccess chunk, BlockState state, LevelReader world, BlockPos pos) {
+    // Paper end - Perf: optimize dirt and snow spreading
         BlockPos blockposition1 = pos.above();
 
-        return SpreadingSnowyDirtBlock.canBeGrass(state, world, pos) && !world.getFluidState(blockposition1).is(FluidTags.WATER);
+        return SpreadingSnowyDirtBlock.canBeGrass(chunk, state, world, pos) && !chunk.getFluidState(blockposition1).is(FluidTags.WATER); // Paper - Perf: optimize dirt and snow spreading
     }
 
     @Override
     protected void randomTick(BlockState state, ServerLevel world, BlockPos pos, RandomSource random) {
         if (this instanceof GrassBlock && world.paperConfig().tickRates.grassSpread != 1 && (world.paperConfig().tickRates.grassSpread < 1 || (net.minecraft.server.MinecraftServer.currentTick + pos.hashCode()) % world.paperConfig().tickRates.grassSpread != 0)) { return; } // Paper - Configurable random tick rates for blocks
-        if (!SpreadingSnowyDirtBlock.canBeGrass(state, world, pos)) {
+        // Paper start - Perf: optimize dirt and snow spreading
+        final net.minecraft.world.level.chunk.ChunkAccess cachedBlockChunk = world.getChunkIfLoaded(pos);
+        if (cachedBlockChunk == null) { // Is this needed?
+            return;
+        }
+        if (!SpreadingSnowyDirtBlock.canBeGrass(cachedBlockChunk, state, world, pos)) {
+            // Paper end - Perf: optimize dirt and snow spreading
             // CraftBukkit start
             if (org.bukkit.craftbukkit.event.CraftEventFactory.callBlockFadeEvent(world, pos, Blocks.DIRT.defaultBlockState()).isCancelled()) {
                 return;
@@ -58,8 +75,20 @@ public abstract class SpreadingSnowyDirtBlock extends SnowyDirtBlock {
                 for (int i = 0; i < 4; ++i) {
                     BlockPos blockposition1 = pos.offset(random.nextInt(3) - 1, random.nextInt(5) - 3, random.nextInt(3) - 1);
 
-                    if (world.getBlockState(blockposition1).is(Blocks.DIRT) && SpreadingSnowyDirtBlock.canPropagate(iblockdata1, world, blockposition1)) {
-                        org.bukkit.craftbukkit.event.CraftEventFactory.handleBlockSpreadEvent(world, pos, blockposition1, (BlockState) iblockdata1.setValue(SpreadingSnowyDirtBlock.SNOWY, isSnowySetting(world.getBlockState(blockposition1.above())))); // CraftBukkit
+                    // Paper start - Perf: optimize dirt and snow spreading
+                    if (pos.getX() == blockposition1.getX() && pos.getY() == blockposition1.getY() && pos.getZ() == blockposition1.getZ()) {
+                        continue;
+                    }
+
+                    final net.minecraft.world.level.chunk.ChunkAccess access;
+                    if (cachedBlockChunk.locX == blockposition1.getX() >> 4 && cachedBlockChunk.locZ == blockposition1.getZ() >> 4) {
+                        access = cachedBlockChunk;
+                    } else {
+                        access = world.getChunkAt(blockposition1);
+                    }
+                    if (access.getBlockState(blockposition1).is(Blocks.DIRT) && SpreadingSnowyDirtBlock.canPropagate(access, iblockdata1, world, blockposition1)) {
+                        org.bukkit.craftbukkit.event.CraftEventFactory.handleBlockSpreadEvent(world, pos, blockposition1, (BlockState) iblockdata1.setValue(SpreadingSnowyDirtBlock.SNOWY, isSnowySetting(access.getBlockState(blockposition1.above())))); // CraftBukkit
+                    // Paper end - Perf: optimize dirt and snow spreading
                     }
                 }
             }