From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Encode42 <me@encode42.dev>
Date: Tue, 23 Mar 2021 15:40:45 -0400
Subject: [PATCH] Config to disable hostile mob spawn on ice


diff --git a/src/main/java/net/minecraft/world/entity/monster/Monster.java b/src/main/java/net/minecraft/world/entity/monster/Monster.java
index 1d66588cfe94d190a34dc376b4b5bff9461a3529..9459255dd06d71dc1728e440e501cb3c2dde616c 100644
--- a/src/main/java/net/minecraft/world/entity/monster/Monster.java
+++ b/src/main/java/net/minecraft/world/entity/monster/Monster.java
@@ -88,6 +88,14 @@ public abstract class Monster extends PathfinderMob implements Enemy {
     }
 
     public static boolean isDarkEnoughToSpawn(ServerLevelAccessor world, BlockPos pos, Random random) {
+        // Purpur start
+        if (!world.getMinecraftWorld().purpurConfig.mobsSpawnOnPackedIce || !world.getMinecraftWorld().purpurConfig.mobsSpawnOnBlueIce) {
+            net.minecraft.world.level.block.state.BlockState spawnBlock = world.getBlockState(pos.below());
+            if ((!world.getMinecraftWorld().purpurConfig.mobsSpawnOnPackedIce && spawnBlock.is(net.minecraft.world.level.block.Blocks.PACKED_ICE)) || (!world.getMinecraftWorld().purpurConfig.mobsSpawnOnBlueIce && spawnBlock.is(net.minecraft.world.level.block.Blocks.BLUE_ICE))) {
+                return false;
+            }
+        }
+        // Purpur end
         if (world.getBrightness(LightLayer.SKY, pos) > random.nextInt(32)) {
             return false;
         } else if (world.getBrightness(LightLayer.BLOCK, pos) > (world.getLevel().paperConfig.maxBlockLightForMonsterSpawning >= 0 ? world.getLevel().paperConfig.maxBlockLightForMonsterSpawning : 0)) { // Paper - configurable max block light level
diff --git a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
index 07dce1b9affedb5ae6888431e713accfe8871c26..5eec80e7266ffe9c5f51eb500c40d680aac53ccc 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
@@ -546,8 +546,12 @@ public class PurpurWorldConfig {
     }
 
     public boolean snowOnBlueIce = true;
+    public boolean mobsSpawnOnPackedIce = true;
+    public boolean mobsSpawnOnBlueIce = true;
     private void iceSettings() {
         snowOnBlueIce = getBoolean("blocks.blue_ice.allow-snow-formation", snowOnBlueIce);
+        mobsSpawnOnPackedIce = getBoolean("blocks.packed_ice.allow-mob-spawns", mobsSpawnOnPackedIce);
+        mobsSpawnOnBlueIce = getBoolean("blocks.blue_ice.allow-mob-spawns", mobsSpawnOnBlueIce);
     }
 
     public boolean lavaInfinite = false;