PaperMC/patches/server-remapped/0374-Do-less-work-if-we-have-a-custom-Bukkit-generator.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Paul Sauve <paul@burngames.net>
Date: Sun, 14 Jul 2019 21:05:03 -0500
Subject: [PATCH] Do less work if we have a custom Bukkit generator

If the Bukkit generator already has a spawn, use it immediately instead
of spending time generating one that we won't use

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 643d75b999c3da006eaaab11f4acd77e807683d4..753e6f609189c589514739bea80007bace3c89d2 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -628,12 +628,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         } else if (debugWorld) {
             iworlddataserver.setSpawn(BlockPos.ZERO.above(), 0.0F);
         } else {
-            BiomeSource worldchunkmanager = chunkgenerator.getBiomeSource();
-            Random random = new Random(world.getSeed());
-            BlockPos blockposition = worldchunkmanager.findBiomeHorizontal(0, world.getSeaLevel(), 0, 256, (biomebase) -> {
-                return biomebase.getMobSettings().playerSpawnFriendly();
-            }, random);
-            ChunkPos chunkcoordintpair = blockposition == null ? new ChunkPos(0, 0) : new ChunkPos(blockposition);
+            // Paper start - moved down
             // CraftBukkit start
             if (world.generator != null) {
                 Random rand = new Random(world.getSeed());
@@ -649,6 +644,15 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                 }
             }
             // CraftBukkit end
+            // Paper start - if the generator created a spawn for us, then there is no need for us to also create a spawn -
+            // only do it if the generator did not
+            BiomeSource worldchunkmanager = chunkgenerator.getBiomeSource();
+            Random random = new Random(world.getSeed());
+            BlockPos blockposition = worldchunkmanager.findBiomeHorizontal(0, world.getSeaLevel(), 0, 256, (biomebase) -> {
+                return biomebase.getMobSettings().playerSpawnFriendly();
+            }, random);
+            ChunkPos chunkcoordintpair = blockposition == null ? new ChunkPos(0, 0) : new ChunkPos(blockposition);
+            // Paper end
 
             if (blockposition == null) {
                 MinecraftServer.LOGGER.warn("Unable to find spawn biome");