Paper/patches/server/0347-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.

== AT ==
public net.minecraft.server.level.ServerPlayer fudgeSpawnLocation(Lnet/minecraft/server/level/ServerLevel;)V

diff --git a/src/main/java/net/minecraft/server/level/ServerPlayer.java b/src/main/java/net/minecraft/server/level/ServerPlayer.java
index 285a9badc1a8b6582b808f0d474bcd22821e2c71..538fe865ad27796371d11123ce03602719a9be68 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayer.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayer.java
@@ -381,7 +381,7 @@ public class ServerPlayer extends Player {
         this.stats = server.getPlayerList().getPlayerStats(this);
         this.advancements = server.getPlayerList().getPlayerAdvancements(this);
         this.setMaxUpStep(1.0F);
-        this.fudgeSpawnLocation(world);
+        // this.fudgeSpawnLocation(world); // Paper - Don't move existing players to world spawn
         this.updateOptions(clientOptions);
 
         this.cachedSingleHashSet = new com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<>(this); // Paper
@@ -615,7 +615,7 @@ public class ServerPlayer extends Player {
                 position = Vec3.atCenterOf(world.getSharedSpawnPos());
             }
             this.setLevel(world);
-            this.setPos(position);
+            this.setPosRaw(position.x(), position.y(), position.z()); // Paper - don't register to chunks yet
         }
         this.gameMode.setLevel((ServerLevel) world);
     }
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index 3f39d64fe673ae0f4b155a5f9e757c981ada96c1..c04db4712ac4127cffe250e404eed9198b377429 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -226,6 +226,7 @@ public abstract class PlayerList {
         // Paper start - Entity#getEntitySpawnReason
         if (nbttagcompound == null) {
             player.spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT; // set Player SpawnReason to DEFAULT on first login
+            player.fudgeSpawnLocation(worldserver1); // Paper - Don't move existing players to world spawn
         }
         // Paper end - Entity#getEntitySpawnReason
         player.setServerLevel(worldserver1);