From d1b5d9b592e1f4d6763a1d8e4873d4752975bb72 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 19 Apr 2020 04:28:29 -0400
Subject: [PATCH] Load Chunks for Login Asynchronously


diff --git a/src/main/java/net/minecraft/server/PlayerList.java b/src/main/java/net/minecraft/server/PlayerList.java
index c2850d50d..d145c4bf1 100644
--- a/src/main/java/net/minecraft/server/PlayerList.java
+++ b/src/main/java/net/minecraft/server/PlayerList.java
@@ -106,8 +106,9 @@ public abstract class PlayerList {
         // CraftBukkit start - Better rename detection
         if (nbttagcompound != null && nbttagcompound.hasKey("bukkit")) {
             NBTTagCompound bukkit = nbttagcompound.getCompound("bukkit");
-            s = bukkit.hasKeyOfType("lastKnownName", 8) ? bukkit.getString("lastKnownName") : s;
+            s = bukkit.hasKeyOfType("lastKnownName", 8) ? bukkit.getString("lastKnownName") : s; // Diff below
         }
+        String lastKnownName = s; // Paper
         if (nbttagcompound == null) entityplayer.moveToSpawn(worldserver); // Paper - only move to spawn on first login, otherwise, stay where you are....
         // CraftBukkit end
 
@@ -132,6 +133,16 @@ public abstract class PlayerList {
         entityplayer.setYawPitch(loc.getYaw(), loc.getPitch());
         // Spigot end
 
+        // Paper start - async load spawn in chunk
+        WorldServer finalWorldserver = worldserver;
+        worldserver.getChunkProvider().getTickingChunkAsync(loc.getBlockX() >> 4, loc.getBlockZ() >> 4, (chunk -> { // use ticking - as it has at least 1 neighbours loaded
+            if (networkmanager.isConnected()) {
+                postChunkLoadJoin(entityplayer, finalWorldserver, nbttagcompound, networkmanager, lastKnownName, networkmanager.getSocketAddress().toString());
+            }
+        }));
+    }
+    private void postChunkLoadJoin(EntityPlayer entityplayer, WorldServer worldserver, NBTTagCompound nbttagcompound, NetworkManager networkmanager, String s, String s1) {
+        // Paper end
         // CraftBukkit - Moved message to after join
         // PlayerList.LOGGER.info("{}[{}] logged in with entity id {} at ({}, {}, {})", entityplayer.getDisplayName().getString(), s1, entityplayer.getId(), entityplayer.locX(), entityplayer.locY(), entityplayer.locZ());
         WorldData worlddata = worldserver.getWorldData();
-- 
2.26.0