0078-Fix-Bugs-with-Spigot-Mob-Spawn-Logic.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 24 Nov 2022 12:24:55 -0300
Subject: [PATCH] Fix Bugs with Spigot Mob Spawn Logic

Spigot drastically altered vanilla mob spawn logic and caused a few issues.
1) Used only spawnable chunks vs entire world for entity counting, resulting in ignoring
other entities in the world, and causing the world to go over its intended limit.

Specially with servers using smaller mob spawn ranges than view distance, as well as affects spawning API

2) Spigot was using 16x16 division instead of vanilla 17x17 division.

This patch returns mob counting to use all loaded chunks, and 17x17 division.

diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
index 73e73f457ceb3c6a7011b7392b05f820d66420e9..3971e7dfdb9b05f44c8e0735d88e95da72be9f22 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -790,7 +790,7 @@ public class Chunk {
             i = this.entitySlices.length - 1;
         }
 
-        this.entitySlices[i].remove(entity);
+        if (!this.entitySlices[i].remove(entity)) return; // PandaSpigot
         // PaperSpigot start - update counts
         if (entity instanceof EntityItem) {
             itemCounts[i]--;
diff --git a/src/main/java/net/minecraft/server/SpawnerCreature.java b/src/main/java/net/minecraft/server/SpawnerCreature.java
index 5dfc94b0d6dd44f2fa283a0c601f448be88a1aa4..3f1f606aa2b0aff755c7657d46eef08eb64781c7 100644
--- a/src/main/java/net/minecraft/server/SpawnerCreature.java
+++ b/src/main/java/net/minecraft/server/SpawnerCreature.java
@@ -23,6 +23,15 @@ public final class SpawnerCreature {
     // Spigot start - get entity count only from chunks being processed in b
     private int getEntityCount(WorldServer server, Class oClass)
     {
+        // PandaSpigot start - use entire world, not just active chunks. Spigot broke vanilla expectations.
+        if (true) {
+            int sum = 0;
+            for (Chunk c : server.chunkProviderServer.chunks.values()) {
+                sum += c.entityCount.get(oClass);
+            }
+            return sum;
+        }
+        // PandaSpigot end
         int i = 0;
         Iterator<Long> it = this.b.iterator();
         while ( it.hasNext() )
@@ -119,10 +128,10 @@ public final class SpawnerCreature {
                     k = worldserver.a(enumcreaturetype.a());
                     int l1 = limit * i / a; // CraftBukkit - use per-world limits
 
-                    if ((mobcnt = getEntityCount(worldserver, enumcreaturetype.a())) <= limit * i / 256) {
+                    if ((mobcnt = getEntityCount(worldserver, enumcreaturetype.a())) <= limit * i / 289) { // PandaSpigot - use 17x17 like vanilla (a at top of file)
                         Iterator iterator1 = this.b.iterator();
 
-                        int moblimit = (limit * i / 256) - mobcnt + 1; // Spigot - up to 1 more than limit
+                        int moblimit = (limit * i / 289) - mobcnt + 1; // Spigot - up to 1 more than limit // PandaSpigot - use 17x17 like vanilla (a at top of file)
                         label115:
                         while (iterator1.hasNext() && (moblimit > 0)) { // Spigot - while more allowed
                             // CraftBukkit start = use LongHash and LongObjectHashMap