From cb4fba79d8fc1806c9b87c7145aff6dc957abd59 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 29 Aug 2018 21:59:22 -0400
Subject: [PATCH] Optimize getChunkIfLoaded type calls

Uses optimized check to avoid major locks and large method.

Will improve inlining across many hot methods.

Improve getBrightness to not do double chunk map lookups.

diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index f7c433b94..fce3f673d 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -376,7 +376,7 @@ public class ChunkProviderServer implements IChunkProvider {
                     continue;
                 }
 
-                Chunk neighbor = this.getChunkAt(chunk.locX + x, chunk.locZ + z, false, false);
+                Chunk neighbor = this.chunks.get(chunk.chunkKey); // Paper
                 if (neighbor != null) {
                     neighbor.setNeighborUnloaded(-x, -z);
                     chunk.setNeighborUnloaded(x, z);
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index a95c8df4b..cd56ca04e 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -161,7 +161,7 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
     }
 
     public Chunk getChunkIfLoaded(int x, int z) {
-        return ((ChunkProviderServer) this.chunkProvider).getChunkAt(x, z, false, false);
+        return ((ChunkProviderServer) this.chunkProvider).chunks.get(ChunkCoordIntPair.a(x, z)); // Paper - optimize getChunkIfLoaded
     }
 
     protected World(IDataManager idatamanager, @Nullable PersistentCollection persistentcollection, WorldData worlddata, WorldProvider worldprovider, MethodProfiler methodprofiler, boolean flag, ChunkGenerator gen, org.bukkit.World.Environment env) {
@@ -717,7 +717,8 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
             blockposition = new BlockPosition(blockposition.getX(), 0, blockposition.getZ());
         }
 
-        return !blockposition.isValidLocation() ? enumskyblock.c : (!this.isLoaded(blockposition) ? enumskyblock.c : this.getChunkAtWorldCoords(blockposition).getBrightness(enumskyblock, blockposition)); // Paper
+        Chunk chunk; // Paper
+        return !blockposition.isValidLocation() ? enumskyblock.c : ((chunk = this.getChunkIfLoaded(blockposition)) == null ? enumskyblock.c : chunk.getBrightness(enumskyblock, blockposition)); // Paper - optimize ifChunkLoaded
     }
 
     public void a(EnumSkyBlock enumskyblock, BlockPosition blockposition, int i) {
@@ -1960,7 +1961,7 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
         if (blockposition.isInvalidYLocation()) { // Paper
             return false;
         } else {
-            Chunk chunk = this.chunkProvider.getChunkAt(blockposition.getX() >> 4, blockposition.getZ() >> 4, false, false);
+            Chunk chunk = this.getChunkIfLoaded(blockposition.getX() >> 4, blockposition.getZ() >> 4); // Paper - optimize ifLoaded
 
             return chunk != null && !chunk.isEmpty();
         }
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index e0b466d0c..2c4465fff 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -218,7 +218,7 @@ public class CraftWorld implements World {
             return false;
         }
 
-        net.minecraft.server.Chunk chunk = world.getChunkProvider().getChunkAt(x, z, false, false);
+        net.minecraft.server.Chunk chunk = world.getChunkIfLoaded(x, z); // Paper - optimize ifLaoded
         if (chunk != null) {
             world.getChunkProvider().unload(chunk);
         }
@@ -237,7 +237,7 @@ public class CraftWorld implements World {
 
     private boolean unloadChunk0(int x, int z, boolean save) {
         Boolean result = MCUtil.ensureMain("Unload Chunk", () -> { // Paper - Ensure never async
-        net.minecraft.server.Chunk chunk = world.getChunkProvider().getChunkAt(x, z, false, false);
+        net.minecraft.server.Chunk chunk = world.getChunkIfLoaded(x, z); // Paper - optimize ifLoaded
         if (chunk == null) {
             return true;
         }
-- 
2.20.1