Paper/CraftBukkit-Patches/0020-Only-count-entities-in-chunks-being-processed-for-th.patch

From f4081e585e922e8a1aca85d344094e4d0e4c3639 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 29 Jan 2013 13:25:53 -0500
Subject: [PATCH] Only count entities in chunks being processed for the spawn
 wave. Fixes mob spawn issues.

---
 .../java/net/minecraft/server/SpawnerCreature.java | 46 ++++++++++++++++++++--
 1 file changed, 43 insertions(+), 3 deletions(-)

diff --git a/src/main/java/net/minecraft/server/SpawnerCreature.java b/src/main/java/net/minecraft/server/SpawnerCreature.java
index 2d1a372..de8f065 100644
--- a/src/main/java/net/minecraft/server/SpawnerCreature.java
+++ b/src/main/java/net/minecraft/server/SpawnerCreature.java
@@ -16,6 +16,7 @@ public final class SpawnerCreature {
 
     private static LongObjectHashMap<Boolean> b = new LongObjectHashMap<Boolean>(); // CraftBukkit - HashMap -> LongObjectHashMap
     protected static final Class[] a = new Class[] { EntitySpider.class, EntityZombie.class, EntitySkeleton.class};
+    private static byte spawnRadius = 0; // Spigot
 
     protected static ChunkPosition getRandomPosition(World world, int i, int j) {
         Chunk chunk = world.getChunkAt(i, j);
@@ -26,6 +27,26 @@ public final class SpawnerCreature {
         return new ChunkPosition(k, i1, l);
     }
 
+    // Spigot start - get entity count only from chunks being processed in b
+    public static final int getEntityCount(WorldServer server, Class oClass) {
+        int i = 0;
+        for (Long coord : b.keySet()) {
+            int x = LongHash.msw(coord);
+            int z = LongHash.lsw(coord);
+            if (!server.chunkProviderServer.unloadQueue.contains(x,z) && server.isChunkLoaded(x, z)) {
+                for (List<Entity> entitySlice : server.getChunkAt(x, z).entitySlices) {
+                    for (Entity entity : entitySlice) {
+                        if (oClass.isAssignableFrom(entity.getClass())) {
+                            ++i;
+                        }
+                    }
+                }
+            }
+        }
+        return i;
+    }
+    // Spigot end
+
     public static final int spawnEntities(WorldServer worldserver, boolean flag, boolean flag1, boolean flag2) {
         if (!flag && !flag1) {
             return 0;
@@ -34,13 +55,24 @@ public final class SpawnerCreature {
 
             int i;
             int j;
+            // Spigot start - limit radius to spawn distance (chunks aren't loaded)
+            if (spawnRadius == 0) {
+                spawnRadius = (byte) worldserver.getWorld().mobSpawnRange;
+                if (spawnRadius > (byte) worldserver.getServer().getViewDistance()) {
+                    spawnRadius = (byte) worldserver.getServer().getViewDistance();
+                }
+                if (spawnRadius > 8) {
+                    spawnRadius = 8;
+                }
+            }
+            // Spigot end
 
             for (i = 0; i < worldserver.players.size(); ++i) {
                 EntityHuman entityhuman = (EntityHuman) worldserver.players.get(i);
                 int k = MathHelper.floor(entityhuman.locX / 16.0D);
 
                 j = MathHelper.floor(entityhuman.locZ / 16.0D);
-                byte b0 = 8;
+                byte b0 = spawnRadius; // Spigot - replace 8 with view distance constrained value
 
                 for (int l = -b0; l <= b0; ++l) {
                     for (int i1 = -b0; i1 <= b0; ++i1) {
@@ -88,13 +120,15 @@ public final class SpawnerCreature {
                 if (limit == 0) {
                     continue;
                 }
+                int mobcnt = 0;
                 // CraftBukkit end
 
-                if ((!enumcreaturetype.d() || flag1) && (enumcreaturetype.d() || flag) && (!enumcreaturetype.e() || flag2) && worldserver.a(enumcreaturetype.a()) <= limit * b.size() / 256) { // CraftBukkit - use per-world limits
+                if ((!enumcreaturetype.d() || flag1) && (enumcreaturetype.d() || flag) && (!enumcreaturetype.e() || flag2) && (mobcnt = getEntityCount(worldserver, enumcreaturetype.a())) <= limit * b.size() / 256) { // CraftBukkit - use per-world limits and use all loaded chunks
                     Iterator iterator = b.keySet().iterator();
 
+                    int moblimit = (limit * b.size() / 256) - mobcnt + 1; // CraftBukkit - up to 1 more than limit
                     label110:
-                    while (iterator.hasNext()) {
+                    while (iterator.hasNext() && (moblimit > 0)) { // Spigot - while more allowed
                         // CraftBukkit start
                         long key = ((Long) iterator.next()).longValue();
 
@@ -158,6 +192,12 @@ public final class SpawnerCreature {
                                                                 a(entityliving, worldserver, f, f1, f2);
                                                                 worldserver.addEntity(entityliving, SpawnReason.NATURAL);
                                                                 // CraftBukkit end
+                                                                // Spigot start
+                                                                moblimit--;
+                                                                if (moblimit <= 0) { // If we're past limit, stop spawn
+                                                                    continue label110;
+                                                                }
+                                                                // Spigot end
                                                                 if (j2 >= entityliving.by()) {
                                                                     continue label110;
                                                                 }
-- 
1.8.1-rc2