From ff03c56abf16576c896a802b68df985d5145ba59 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 4 Jul 2018 03:39:51 -0400
Subject: [PATCH] Avoid Chunk Lookups for Entity/TileEntity Current Chunk

In many places where we simply want the current chunk the entity
is in, instead of doing a hashmap lookup for it, we now have access
to the object directly on the Entity/TileEntity object we can directly grab.

Use that local value instead to reduce lookups in many hot places.

diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index edd8e7810f..5349a3a8bc 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -761,7 +761,8 @@ public abstract class World implements IIBlockAccess, GeneratorAccess, AutoClose
             if (!tileentity.isRemoved() && tileentity.hasWorld()) {
                 BlockPosition blockposition = tileentity.getPosition();
 
-                if (this.isLoaded(blockposition) && this.getWorldBorder().a(blockposition)) {
+                Chunk currentChunk = tileentity.getCurrentChunk(); // Paper
+                if (currentChunk != null && this.getWorldBorder().a(blockposition)) { // Paper
                     try {
                         gameprofilerfiller.a(() -> {
                             return String.valueOf(TileEntityTypes.a(tileentity.q()));
@@ -795,7 +796,7 @@ public abstract class World implements IIBlockAccess, GeneratorAccess, AutoClose
                 this.tileEntityListTick.remove(tileTickPosition--);
                 // Spigot end
                 //this.tileEntityList.remove(tileentity); // Paper - remove unused list
-                if (this.isLoaded(tileentity.getPosition())) {
+                if (tileentity.getCurrentChunk() != null ) { // Paper - avoid lookups
                     this.getChunkAtWorldCoords(tileentity.getPosition()).removeTileEntity(tileentity.getPosition());
                 }
             }
@@ -816,8 +817,9 @@ public abstract class World implements IIBlockAccess, GeneratorAccess, AutoClose
                     }
                     // CraftBukkit end */
 
-                    if (this.isLoaded(tileentity1.getPosition())) {
-                        Chunk chunk = this.getChunkAtWorldCoords(tileentity1.getPosition());
+                    Chunk chunk = tileentity1.getCurrentChunk(); // Paper
+                    if (chunk != null) { // Paper
+                        //Chunk chunk = this.getChunkAtWorldCoords(tileentity1.getPosition()); // Paper
                         IBlockData iblockdata = chunk.getType(tileentity1.getPosition());
 
                         chunk.setTileEntity(tileentity1.getPosition(), tileentity1);
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index 38d673d8fe..bb2059fda7 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -1068,7 +1068,7 @@ public class WorldServer extends World {
         }
 
         this.entitiesByUUID.remove(entity.getUniqueID());
-        this.getChunkProvider().removeEntity(entity);
+        if (entity.getCurrentChunk() != null ) this.getChunkProvider().removeEntity(entity); // Paper
         if (entity instanceof EntityPlayer) {
             EntityPlayer entityplayer = (EntityPlayer) entity;
 
@@ -1128,9 +1128,12 @@ public class WorldServer extends World {
     }
 
     private void removeEntityFromChunk(Entity entity) {
-        IChunkAccess ichunkaccess = this.getChunkAt(entity.chunkX, entity.chunkZ, ChunkStatus.FULL, false);
+        // Paper start
+        if (!entity.inChunk) return;
+        IChunkAccess ichunkaccess = this.getChunkIfLoaded(entity.chunkX, entity.chunkZ);
+        // Paper start
 
-        if (ichunkaccess instanceof Chunk) {
+        if (ichunkaccess != null) {
             ((Chunk) ichunkaccess).b(entity);
         }
 
-- 
2.21.0