Paper/Spigot-Server-Patches/0430-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 d4c6d26a61bf3519333cb99f04f28afaf4764cac..67eaac661a03742051e63551e6f18e1475a19e99 100644
--- a/src/main/java/net/minecraft/server/EntityPlayer.java
+++ b/src/main/java/net/minecraft/server/EntityPlayer.java
@@ -123,7 +123,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
         this.serverStatisticManager = minecraftserver.getPlayerList().getStatisticManager(this);
         this.advancementDataPlayer = minecraftserver.getPlayerList().f(this);
         this.G = 1.0F;
-        this.c(worldserver);
+        //this.c(worldserver); // Paper - don't move to spawn on login, only first join
         this.co = minecraftserver.a(this);
 
         this.cachedSingleHashSet = new com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<>(this); // Paper
@@ -174,6 +174,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
     }
     // CraftBukkit end
 
+    public final void moveToSpawn(WorldServer worldserver) { c(worldserver); } // Paper - OBFHELPER
     private void c(WorldServer worldserver) {
         BlockPosition blockposition = worldserver.getSpawn();
 
@@ -351,7 +352,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
                 position = Vec3D.a(((WorldServer) 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.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 a124b47f07dd223151f23cc27a6e5ee5921b7942..a1987b17adb5fa8fdeb601da948839fb1fd35aaf 100644
--- a/src/main/java/net/minecraft/server/PlayerList.java
+++ b/src/main/java/net/minecraft/server/PlayerList.java
@@ -134,6 +134,8 @@ public abstract class PlayerList {
             worldserver1 = worldserver;
         }
 
+        if (nbttagcompound == null) entityplayer.moveToSpawn(worldserver1); // Paper - only move to spawn on first login, otherwise, stay where you are....
+
         entityplayer.spawnIn(worldserver1);
         entityplayer.playerInteractManager.a((WorldServer) entityplayer.world);
         String s1 = "local";