From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: violetc <58360096+s-yh-china@users.noreply.github.com>
Date: Mon, 15 Aug 2022 08:23:51 +0800
Subject: [PATCH] Use thread unsafe random for mob spawning

This patch is Powered by Pufferfish(https://github.com/pufferfish-gg/Pufferfish)

diff --git a/src/main/java/net/minecraft/world/level/NaturalSpawner.java b/src/main/java/net/minecraft/world/level/NaturalSpawner.java
index dca0d9611593a0f3b921b314b4b458cc95f08ebc..612d536f8a1b4e45d7431dc8bbd1c7aa631a3575 100644
--- a/src/main/java/net/minecraft/world/level/NaturalSpawner.java
+++ b/src/main/java/net/minecraft/world/level/NaturalSpawner.java
@@ -419,12 +419,21 @@ public final class NaturalSpawner {
 
     private static BlockPos getRandomPosWithin(Level world, LevelChunk chunk) {
         ChunkPos chunkcoordintpair = chunk.getPos();
-        int i = chunkcoordintpair.getMinBlockX() + world.random.nextInt(16);
-        int j = chunkcoordintpair.getMinBlockZ() + world.random.nextInt(16);
-        int k = chunk.getHeight(Heightmap.Types.WORLD_SURFACE, i, j) + 1;
-        int l = Mth.randomBetweenInclusive(world.random, world.getMinBuildHeight(), k);
-
-        return new BlockPos(i, l, j);
+        // Leaves start - use thread unsafe random
+        if (top.leavesmc.leaves.LeavesConfig.useMoreThreadUnsafeRandom) {
+            int i = chunkcoordintpair.getMinBlockX() + world.getThreadUnsafeRandom().nextInt(16);
+            int j = chunkcoordintpair.getMinBlockZ() + world.getThreadUnsafeRandom().nextInt(16);
+            int k = chunk.getHeight(Heightmap.Types.WORLD_SURFACE, i, j) + 1;
+            int l = Mth.randomBetweenInclusive(world.getThreadUnsafeRandom(), world.getMinBuildHeight(), k);
+            return new BlockPos(i, l, j);
+        } else {
+            int i = chunkcoordintpair.getMinBlockX() + world.random.nextInt(16);
+            int j = chunkcoordintpair.getMinBlockZ() + world.random.nextInt(16);
+            int k = chunk.getHeight(Heightmap.Types.WORLD_SURFACE, i, j) + 1;
+            int l = Mth.randomBetweenInclusive(world.random, world.getMinBuildHeight(), k);
+            return new BlockPos(i, l, j);
+        }
+        // Leaves end - use thread unsafe random
     }
 
     public static boolean isValidEmptySpawnBlock(BlockGetter blockView, BlockPos pos, BlockState state, FluidState fluidState, EntityType<?> entityType) {
diff --git a/src/main/java/top/leavesmc/leaves/LeavesConfig.java b/src/main/java/top/leavesmc/leaves/LeavesConfig.java
index 076074b70f95141011b3f71948b9d2581306db4e..ba58171708fd3362fe76af608d657e94fd2b3c01 100644
--- a/src/main/java/top/leavesmc/leaves/LeavesConfig.java
+++ b/src/main/java/top/leavesmc/leaves/LeavesConfig.java
@@ -299,6 +299,11 @@ public final class LeavesConfig {
         entityTargetFindingOptimization = getBoolean("settings.performance.entity-target-find-optimization", entityTargetFindingOptimization);
     }
 
+    public static boolean useMoreThreadUnsafeRandom = true;
+    private static void useMoreThreadUnsafeRandom() {
+        useMoreThreadUnsafeRandom = getBoolean("settings.performance.use-more-thread-unsafe-random", useMoreThreadUnsafeRandom);
+    }
+
     public static final class WorldConfig {
 
         public final String worldName;