Paper/Spigot-Server-Patches/0460-Don-t-move-existing-players-to-world-spawn.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 9 Apr 2020 21:20:33 -0400
Subject: [PATCH] Don't move existing players to world spawn

This can cause a nasty server lag the spawn chunks are not kept loaded
or they aren't finished loading yet, or if the world spawn radius is
larger than the keep loaded range.

By skipping this, we avoid potential for a large spike on server start.

diff --git a/src/main/java/net/minecraft/server/EntityPlayer.java b/src/main/java/net/minecraft/server/EntityPlayer.java
index f4215d38acef8018f09dff5f379c14336647687d..4e4c0acc6c103c85b7ba2a390a54d3513939d547 100644
--- a/src/main/java/net/minecraft/server/EntityPlayer.java
+++ b/src/main/java/net/minecraft/server/EntityPlayer.java
@@ -114,7 +114,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
         this.serverStatisticManager = minecraftserver.getPlayerList().getStatisticManager(this);
         this.advancementDataPlayer = minecraftserver.getPlayerList().f(this);
         this.H = 1.0F;
-        this.a(worldserver);
+        //this.a(worldserver); // Paper - don't move to spawn on login, only first join
 
         this.cachedSingleHashSet = new com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<>(this); // Paper
 
@@ -162,6 +162,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
     }
     // CraftBukkit end
 
+    public void moveToSpawn(WorldServer worldserver) { a(worldserver); } // Paper - OBFHELPER
     private void a(WorldServer worldserver) {
         BlockPosition blockposition = worldserver.getSpawn();
 
@@ -302,7 +303,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
                 position = new Vec3D(world.getSpawn());
             }
             this.world = world;
-            this.setPosition(position.getX(), position.getY(), position.getZ());
+            this.setPositionRaw(position.getX(), position.getY(), position.getZ()); // Paper - don't register to chunks yet
         }
         this.dimension = ((WorldServer) this.world).getWorldProvider().getDimensionManager();
         this.playerInteractManager.a((WorldServer) world);
diff --git a/src/main/java/net/minecraft/server/PlayerList.java b/src/main/java/net/minecraft/server/PlayerList.java
index 32d8cc7f22aaddef2e68506eeb44e01795f2aff5..ab2831830ad3a4cec0671d189e0534c843b47f5e 100644
--- a/src/main/java/net/minecraft/server/PlayerList.java
+++ b/src/main/java/net/minecraft/server/PlayerList.java
@@ -108,6 +108,7 @@ public abstract class PlayerList {
             NBTTagCompound bukkit = nbttagcompound.getCompound("bukkit");
             s = bukkit.hasKeyOfType("lastKnownName", 8) ? bukkit.getString("lastKnownName") : s;
         }
+        if (nbttagcompound == null) entityplayer.moveToSpawn(worldserver); // Paper - only move to spawn on first login, otherwise, stay where you are....
         // CraftBukkit end
 
         entityplayer.spawnIn(worldserver);