From 8ec12880792976678433b2c691c68aeab11b08ae Mon Sep 17 00:00:00 2001
From: DeadlyMC <modding.deadlymc@gmail.com>
Date: Fri, 11 Oct 2019 18:28:37 +0530
Subject: [PATCH 1/3] flatWorldStructureSpawning

---
 .../mixins/FlatChunkGeneratorMixin.java       | 58 +++++++++++++++++++
 .../java/carpet/settings/CarpetSettings.java  |  6 ++
 src/main/resources/carpet.mixins.json         |  1 +
 3 files changed, 65 insertions(+)
 create mode 100644 src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java

diff --git a/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
new file mode 100644
index 00000000..b4fdef36
--- /dev/null
+++ b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
@@ -0,0 +1,58 @@
+package carpet.mixins;
+
+import carpet.settings.CarpetSettings;
+import net.minecraft.entity.EntityCategory;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IWorld;
+import net.minecraft.world.biome.Biome;
+import net.minecraft.world.biome.source.BiomeSource;
+import net.minecraft.world.gen.chunk.ChunkGenerator;
+import net.minecraft.world.gen.chunk.FlatChunkGenerator;
+import net.minecraft.world.gen.chunk.FlatChunkGeneratorConfig;
+import net.minecraft.world.gen.feature.Feature;
+import org.spongepowered.asm.mixin.Mixin;
+
+import java.util.List;
+
+@Mixin(FlatChunkGenerator.class)
+public abstract class FlatChunkGeneratorMixin extends ChunkGenerator<FlatChunkGeneratorConfig>
+{
+    public FlatChunkGeneratorMixin(IWorld iWorld, BiomeSource biome, FlatChunkGeneratorConfig chunkGeneratorConfig)
+    {
+        super(iWorld, biome, chunkGeneratorConfig);
+    }
+    
+    @Override
+    public List<Biome.SpawnEntry> getEntitySpawnList(EntityCategory category, BlockPos pos)
+    {
+        if (CarpetSettings.flatWorldStructureSpawning)
+        {
+            if (Feature.SWAMP_HUT.method_14029(this.world, pos))
+            {
+                if (category == EntityCategory.MONSTER)
+                {
+                    return Feature.SWAMP_HUT.getMonsterSpawns();
+                }
+        
+                if (category == EntityCategory.CREATURE)
+                {
+                    return Feature.SWAMP_HUT.getCreatureSpawns();
+                }
+            }
+            else if (category == EntityCategory.MONSTER)
+            {
+                if (Feature.PILLAGER_OUTPOST.isApproximatelyInsideStructure(this.world, pos))
+                {
+                    return Feature.PILLAGER_OUTPOST.getMonsterSpawns();
+                }
+        
+                if (Feature.OCEAN_MONUMENT.isApproximatelyInsideStructure(this.world, pos))
+                {
+                    return Feature.OCEAN_MONUMENT.getMonsterSpawns();
+                }
+            }
+        }
+        
+        return super.getEntitySpawnList(category, pos);
+    }
+}
diff --git a/src/main/java/carpet/settings/CarpetSettings.java b/src/main/java/carpet/settings/CarpetSettings.java
index 2fff5bb4..f707a39d 100644
--- a/src/main/java/carpet/settings/CarpetSettings.java
+++ b/src/main/java/carpet/settings/CarpetSettings.java
@@ -445,4 +445,10 @@ public class CarpetSettings
             category = BUGFIX
     )
     public static boolean horseWanderingFix = false;
+    
+    @Rule(
+            desc = "Allows structure mobs to spawn in flat worlds",
+            category = {EXPERIMENTAL, CREATIVE}
+    )
+    public static boolean flatWorldStructureSpawning = false;
 }
diff --git a/src/main/resources/carpet.mixins.json b/src/main/resources/carpet.mixins.json
index 6d0fc634..901905a0 100644
--- a/src/main/resources/carpet.mixins.json
+++ b/src/main/resources/carpet.mixins.json
@@ -67,6 +67,7 @@
     "PlayerEntity_parrotMixin",
     "SaplingBlockMixin",
     "EntityMixin",
+    "FlatChunkGeneratorMixin",
 
     "GuardianEntityMixin",
     "DesertPyramidFeatureMixin",

From 0957bb9b0cf27be6b622597475a697e4df1980de Mon Sep 17 00:00:00 2001
From: DeadlyMC <modding.deadlymc@gmail.com>
Date: Fri, 11 Oct 2019 20:19:36 +0530
Subject: [PATCH 2/3] forgot to add desert temple spawns

---
 src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
index b4fdef36..b76d6cfe 100644
--- a/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
+++ b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
@@ -45,6 +45,14 @@ public abstract class FlatChunkGeneratorMixin extends ChunkGenerator<FlatChunkGe
                 {
                     return Feature.PILLAGER_OUTPOST.getMonsterSpawns();
                 }
+    
+                if (CarpetSettings.huskSpawningInTemples)
+                {
+                    if (Feature.DESERT_PYRAMID.isApproximatelyInsideStructure(this.world, pos))
+                    {
+                        return Feature.DESERT_PYRAMID.getMonsterSpawns();
+                    }
+                }
         
                 if (Feature.OCEAN_MONUMENT.isApproximatelyInsideStructure(this.world, pos))
                 {

From a8936c9efe36493a4b0f837f03fc117c48ef5622 Mon Sep 17 00:00:00 2001
From: DeadlyMC <modding.deadlymc@gmail.com>
Date: Fri, 11 Oct 2019 20:31:02 +0530
Subject: [PATCH 3/3] added nether and end mobs

---
 .../mixins/FlatChunkGeneratorMixin.java       | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
index b76d6cfe..91bfc51c 100644
--- a/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
+++ b/src/main/java/carpet/mixins/FlatChunkGeneratorMixin.java
@@ -1,6 +1,7 @@
 package carpet.mixins;
 
 import carpet.settings.CarpetSettings;
+import net.minecraft.block.Blocks;
 import net.minecraft.entity.EntityCategory;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IWorld;
@@ -58,6 +59,24 @@ public abstract class FlatChunkGeneratorMixin extends ChunkGenerator<FlatChunkGe
                 {
                     return Feature.OCEAN_MONUMENT.getMonsterSpawns();
                 }
+    
+                if (Feature.NETHER_BRIDGE.isInsideStructure(this.world, pos))
+                {
+                    return Feature.NETHER_BRIDGE.getMonsterSpawns();
+                }
+    
+                if (Feature.NETHER_BRIDGE.isApproximatelyInsideStructure(this.world, pos) && this.world.getBlockState(pos.down()).getBlock() == Blocks.NETHER_BRICKS)
+                {
+                    return Feature.NETHER_BRIDGE.getMonsterSpawns();
+                }
+    
+                if (CarpetSettings.shulkerSpawningInEndCities)
+                {
+                    if (Feature.END_CITY.isInsideStructure(this.world, pos))
+                    {
+                        return Feature.END_CITY.getMonsterSpawns();
+                    }
+                }
             }
         }