Experimental nether biomes API (#496)

* Add nether biomes API

* Update fabric-biomes-v1.mixins.json

* fixed license

* smarter injection point

* Apply suggestions from coderbot's review

Co-Authored-By: coderbot16 <coderbot16@gmail.com>

* fix code style

* remove redundant import

* improve docs and update yarn version

* Apply suggestions from code review

Co-Authored-By: coderbot16 <coderbot16@gmail.com>
Co-Authored-By: Juuxel <6596629+Juuxel@users.noreply.github.com>

* bump version

* mark classes as final

* Changes from modmuss's review

add 1.16 dependency, merge NetherBiomesImpl into InternalBiomeData, fix code style, and fix mixin target

* Update build.gradle

* Update API to inform users that it is experimental

* remove beta annotion

* optimize imports

Co-authored-by: coderbot16 <coderbot16@gmail.com>
Co-authored-by: Juuxel <6596629+Juuxel@users.noreply.github.com>

build.gradle

@@ -14,7 +14,7 @@ def ENV = System.getenv()
 class Globals {
 	static def baseVersion = "0.4.31"
 	static def mcVersion = "20w06a"
-	static def yarnVersion = "+build.1"
+	static def yarnVersion = "+build.8"
 }
 
 import org.apache.commons.codec.digest.DigestUtils

fabric-biomes-v1/build.gradle

@@ -1,2 +1,2 @@
 archivesBaseName = "fabric-biomes-v1"
-version = getSubprojectVersion(project, "0.1.5")
+version = getSubprojectVersion(project, "0.2.0")

fabric-biomes-v1/src/main/java/net/fabricmc/fabric/api/biomes/v1/NetherBiomes.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.api.biomes.v1;
+
+import net.minecraft.world.biome.Biome;
+
+import net.fabricmc.fabric.impl.biome.InternalBiomeData;
+
+/**
+ * API that exposes the internals of Minecraft's nether biome code.
+ */
+public final class NetherBiomes {
+	private NetherBiomes() { }
+
+	/**
+	 * Adds a biome to the Nether generator. Biomes must set their own noise values in the {@link Biome.MixedNoisePoint} class for the biome to properly generate.
+	 *
+	 * @deprecated Experimental feature, may be removed or changed without further notice due to potential changes to Nether biomes in subsequent snapshots.
+	 * @param biome The biome to add. Must not be null.
+	 * @see Biome.MixedNoisePoint
+	 */
+	@Deprecated
+	public static void addNetherBiome(Biome biome) {
+		InternalBiomeData.addNetherBiome(biome);
+	}
+}

fabric-biomes-v1/src/main/java/net/fabricmc/fabric/impl/biome/InternalBiomeData.java

@@ -18,6 +18,7 @@ package net.fabricmc.fabric.impl.biome;
 
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.Collections;
 import java.util.EnumMap;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -48,6 +49,8 @@ public final class InternalBiomeData {
 	private static final Map<Biome, VariantTransformer> OVERWORLD_VARIANT_TRANSFORMERS = new HashMap<>();
 	private static final Map<Biome, Biome> OVERWORLD_RIVER_MAP = new HashMap<>();
 
+	private static final Set<Biome> NETHER_BIOMES = new HashSet<>();
+
 	private static final Set<Biome> SPAWN_BIOMES = new HashSet<>();
 
 	private static Method injectBiomeMethod = null;
@@ -123,6 +126,11 @@ public final class InternalBiomeData {
 		}
 	}
 
+	public static void addNetherBiome(Biome biome) {
+		Preconditions.checkArgument(biome != null, "Biome is null");
+		NETHER_BIOMES.add(biome);
+	}
+
 	public static Set<Biome> getSpawnBiomes() {
 		return SPAWN_BIOMES;
 	}
@@ -151,6 +159,10 @@ public final class InternalBiomeData {
 		return OVERWORLD_VARIANT_TRANSFORMERS;
 	}
 
+	public static Set<Biome> getNetherBiomes() {
+		return Collections.unmodifiableSet(NETHER_BIOMES);
+	}
+
 	private static class DefaultHillsData {
 		private static final ImmutableMap<Biome, Biome> DEFAULT_HILLS;
 

fabric-biomes-v1/src/main/java/net/fabricmc/fabric/mixin/biome/MixinTheNetherDimension.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.mixin.biome;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.ModifyArg;
+
+import net.minecraft.world.biome.Biome;
+import net.minecraft.world.dimension.TheNetherDimension;
+
+import net.fabricmc.fabric.impl.biome.InternalBiomeData;
+
+@Mixin(TheNetherDimension.class)
+public class MixinTheNetherDimension {
+	@ModifyArg(method = "createChunkGenerator", at = @At(value = "INVOKE", target = "Lnet/minecraft/world/biome/source/MultiNoiseBiomeSourceConfig;withBiomes(Ljava/util/Set;)Lnet/minecraft/world/biome/source/MultiNoiseBiomeSourceConfig;"))
+	protected Set<Biome> modifyNetherBiomes(Set<Biome> set) {
+		// the provided set is immutable, so we construct our own
+		Set<Biome> newSet = new HashSet<>(set);
+		newSet.addAll(InternalBiomeData.getNetherBiomes());
+		return newSet;
+	}
+}

fabric-biomes-v1/src/main/resources/fabric-biomes-v1.mixins.json

@@ -8,6 +8,7 @@
     "MixinAddRiversLayer",
     "MixinBiomeSource",
     "MixinSetBaseBiomesLayer",
+    "MixinTheNetherDimension",
     "MixinVanillaLayeredBiomeSource"
   ],
   "injectors": {

fabric-biomes-v1/src/main/resources/fabric.mod.json

@@ -16,7 +16,8 @@
     "FabricMC"
   ],
   "depends": {
-    "fabricloader": ">=0.4.0"
+    "fabricloader": ">=0.4.0",
+    "minecraft": ">=1.16-alpha.20.6.a"
   },
   "description": "Hooks for adding biomes to the default world generator.",
   "mixins": [