Merge pull request #22 from valoeghese/tsuchimikado_motoharu

chunk gen events

src/main/java/io/github/fabriccommunity/events/mixin/advancement/MixinInventoryChangedCriterion.java

@@ -11,6 +11,9 @@
 import net.minecraft.item.ItemStack;
 import net.minecraft.server.network.ServerPlayerEntity;
 
+/**
+ * @author B0undaryBreaker
+ */
 @Mixin(InventoryChangedCriterion.class)
 public class MixinInventoryChangedCriterion {
 	@Inject(method = "trigger(Lnet/minecraft/server/network/ServerPlayerEntity;Lnet/minecraft/entity/player/PlayerInventory;Lnet/minecraft/item/ItemStack;III)V", at = @At("HEAD"))

src/main/java/io/github/fabriccommunity/events/mixin/advancement/MixinItemDurabilityChangedCriterion.java

@@ -10,6 +10,9 @@
 import net.minecraft.item.ItemStack;
 import net.minecraft.server.network.ServerPlayerEntity;
 
+/**
+ * @author B0undaryBreaker
+ */
 @Mixin(ItemDurabilityChangedCriterion.class)
 public class MixinItemDurabilityChangedCriterion {
 	@Inject(method = "trigger", at = @At("HEAD"))

src/main/java/io/github/fabriccommunity/events/mixin/advancement/MixinOnKilledCriterion.java

@@ -12,6 +12,9 @@
 import net.minecraft.entity.damage.DamageSource;
 import net.minecraft.server.network.ServerPlayerEntity;
 
+/**
+ * @author B0undaryBreaker
+ */
 @Mixin(OnKilledCriterion.class)
 public class MixinOnKilledCriterion {
 	@Inject(method = "trigger", at = @At("HEAD"))

src/main/java/io/github/fabriccommunity/events/mixin/advancement/MixinPlayerHurtEntityCriterion.java

@@ -11,6 +11,9 @@
 import net.minecraft.entity.damage.DamageSource;
 import net.minecraft.server.network.ServerPlayerEntity;
 
+/**
+ * @author b0undary
+ */
 @Mixin(PlayerHurtEntityCriterion.class)
 public class MixinPlayerHurtEntityCriterion {
 	@Inject(method = "trigger", at = @At("HEAD"))

src/main/java/io/github/fabriccommunity/events/mixin/spawn/MixinSpawnHelper.java

@@ -1,14 +1,24 @@
 package io.github.fabriccommunity.events.mixin.spawn;
 
+import java.util.Random;
+
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.Redirect;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
 import io.github.fabriccommunity.events.impl.EntitySpawnImpl;
+import io.github.fabriccommunity.events.world.WorldGenEvents;
 import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityType;
 import net.minecraft.server.world.ServerWorld;
+import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.ServerWorldAccess;
 import net.minecraft.world.SpawnHelper;
+import net.minecraft.world.WorldView;
+import net.minecraft.world.biome.Biome;
 
 /**
  * @author Valoeghese
@@ -30,4 +40,14 @@ private static void entitySpawnEventNatural(ServerWorld self, Entity entity) {
 	private static void entitySpawnEventChunk(ServerWorldAccess self, Entity entity) {
 		EntitySpawnImpl.spawnEntityV(self, entity);
 	}
+
+	@Inject(at = @At("RETURN"), method = "populateEntities")
+	private static void onPopulateEntities(ServerWorldAccess world, Biome biome, int chunkX, int chunkZ, Random random, CallbackInfo info) {
+		WorldGenEvents.POPULATE_ENTITIES.invoker().onPopulateEntities(world, biome, chunkX, chunkZ, random, MixinSpawnHelper::getEntitySpawnPos);
+	}
+
+	@Shadow
+	private static BlockPos getEntitySpawnPos(WorldView world, EntityType<?> entityType, int x, int z) {
+		throw new RuntimeException("Mixin getEntitySpawnPos failed to apply!");
+	}
 }

src/main/java/io/github/fabriccommunity/events/mixin/world/MixinChunkGenerator.java

@@ -0,0 +1,29 @@
+package io.github.fabriccommunity.events.mixin.world;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import io.github.fabriccommunity.events.world.WorldGenEvents;
+import net.minecraft.world.ChunkRegion;
+import net.minecraft.world.gen.StructureAccessor;
+import net.minecraft.world.gen.chunk.ChunkGenerator;
+
+/**
+ * @author Valoeghese
+ */
+@Mixin(ChunkGenerator.class)
+public class MixinChunkGenerator {
+	@Inject(at = @At("HEAD"), method = "generateFeatures", cancellable = true)
+	private void onStartGenerateFeatures(ChunkRegion region, StructureAccessor accessor, CallbackInfo info) {
+		if (WorldGenEvents.GENERATE_FEATURES_START.invoker().onStartGenerateFeatures((ChunkGenerator) (Object) this, region, accessor)) {
+			info.cancel();
+		}
+	}
+
+	@Inject(at = @At("RETURN"), method = "generateFeatures")
+	private void onEndGenerateFeatures(ChunkRegion region, StructureAccessor accessor, CallbackInfo info) {
+		WorldGenEvents.GENERATE_FEATURES_END.invoker().onEndGenerateFeatures((ChunkGenerator) (Object) this, region, accessor);
+	}
+}

src/main/java/io/github/fabriccommunity/events/play/PlayerAdvancementEvents.java

@@ -39,10 +39,10 @@ public class PlayerAdvancementEvents {
 	 */
 	public static final Event<ItemDurabilityChanged> ITEM_DURABILITY_CHANGED_WILDCARD = EventFactory.createArrayBacked(ItemDurabilityChanged.class,
 			listeners -> (player, stack, damage) -> {
-		for (ItemDurabilityChanged listener : listeners) {
-			listener.onItemDurabilityChange(player, stack, damage);
-		}
-	});
+				for (ItemDurabilityChanged listener : listeners) {
+					listener.onItemDurabilityChange(player, stack, damage);
+				}
+			});
 
 	/**
 	 * An event run when the durability of a stack of <item> is changed.
@@ -58,10 +58,10 @@ public static Event<ItemDurabilityChanged> itemDurabilityChanged(Item item) {
 	 */
 	public static final Event<PlayerHurtEntity> PLAYER_HURT_ENTITY_WILDCARD = EventFactory.createArrayBacked(PlayerHurtEntity.class,
 			listeners -> (attacker, victim, source, dealt, taken, blocked) -> {
-		for (PlayerHurtEntity listener : listeners) {
-			listener.onPlayerHurtEntity(attacker, victim, source, dealt, taken, blocked);
-		}
-	});
+				for (PlayerHurtEntity listener : listeners) {
+					listener.onPlayerHurtEntity(attacker, victim, source, dealt, taken, blocked);
+				}
+			});
 
 	/**
 	 * An event run when a player hurts a specific type of entity.
@@ -77,10 +77,10 @@ public static Event<PlayerHurtEntity> playerHurtEntity(EntityType<?> type) {
 	 */
 	public static final Event<PlayerKilledEntity> PLAYER_KILLED_ENTITY_WILDCARD = EventFactory.createArrayBacked(PlayerKilledEntity.class,
 			listeners -> (killer, victim, source) -> {
-		for (PlayerKilledEntity listener : listeners) {
-			listener.onPlayerKillEntity(killer, victim, source);
-		}
-	});
+				for (PlayerKilledEntity listener : listeners) {
+					listener.onPlayerKillEntity(killer, victim, source);
+				}
+			});
 
 	/**
 	 * An event run when a play kills a specific type of entity.

src/main/java/io/github/fabriccommunity/events/util/SpawnPosGetter.java

@@ -0,0 +1,14 @@
+package io.github.fabriccommunity.events.util;
+
+import net.minecraft.entity.EntityType;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.WorldView;
+
+/**
+ * Used by {@link WorldGenEvents.POPULATE_ENTITIES} as an accessible way to get the entity spawn pos for given x/z coordinates.
+ * @author Valoeghese
+ */
+@FunctionalInterface
+public interface SpawnPosGetter {
+	BlockPos getEntitySpawnPos(WorldView world, EntityType<?> entityType, int x, int z);
+}

src/main/java/io/github/fabriccommunity/events/world/WorldGenEvents.java

@@ -1,13 +1,19 @@
 package io.github.fabriccommunity.events.world;
 
+import java.util.Random;
 import java.util.concurrent.atomic.AtomicReference;
 
+import io.github.fabriccommunity.events.util.SpawnPosGetter;
 import net.fabricmc.fabric.api.event.Event;
 import net.fabricmc.fabric.api.event.EventFactory;
 import net.minecraft.util.ActionResult;
 import net.minecraft.util.registry.Registry;
+import net.minecraft.world.ChunkRegion;
+import net.minecraft.world.ServerWorldAccess;
 import net.minecraft.world.biome.Biome;
 import net.minecraft.world.biome.source.BiomeSource;
+import net.minecraft.world.gen.StructureAccessor;
+import net.minecraft.world.gen.chunk.ChunkGenerator;
 
 /**
  * A collection of events pertaining to world generation.
@@ -28,8 +34,39 @@ public final class WorldGenEvents {
 		return ActionResult.PASS;
 	});
 
+	/**
+	 * Called on feature placement to allow for mods to modify the chunk without using mojang's "features", or even replace chunk feature population, among various other things.
+	 */
+	public static final Event<GenerateFeaturesStart> GENERATE_FEATURES_START = EventFactory.createArrayBacked(GenerateFeaturesStart.class, listeners -> (generator, region, structures) -> {
+		for (GenerateFeaturesStart listener : listeners) {
+			if (listener.onStartGenerateFeatures(generator, region, structures)) {
+				return true;
+			}
+		}
+
+		return false;
+	});
+
 	/**
 	 * Called at the end of biome placement to allow for mods to edit the biome to be placed.
+	 */
+	public static final Event<GenerateFeaturesEnd> GENERATE_FEATURES_END = EventFactory.createArrayBacked(GenerateFeaturesEnd.class, listeners -> (generator, region, structures) -> {
+		for (GenerateFeaturesEnd listener : listeners) {
+			listener.onEndGenerateFeatures(generator, region, structures);
+		}
+	});
+
+	/**
+	 * Called on chunk generation entity population to allow for mods to spawn entities with their own logic.
+	 */
+	public static final Event<PopulateEntities> POPULATE_ENTITIES = EventFactory.createArrayBacked(PopulateEntities.class, listeners -> (world, biome, chunkX, chunkZ, random, spawnPosGetter) -> {
+		for (PopulateEntities listener : listeners) {
+			listener.onPopulateEntities(world, biome, chunkX, chunkZ, random, spawnPosGetter);
+		}
+	});
+
+	/**
+	 * Called on feature placement to allow for mods to modify the chunk without using mojang's "features", among various other things.
 	 * @author Valoeghese
 	 */
 	@FunctionalInterface
@@ -51,4 +88,33 @@ public interface BiomePlacement {
 		 */
 		ActionResult onBiomePlace(BiomeSource source, Registry<Biome> registry, final Biome original, AtomicReference<Biome> biome, int genX, int genZ);
 	}
+
+	/**
+	 * Called on feature placement to allow for mods to modify the chunk without using mojang's "features", or even replace chunk feature population, among various other things.
+	 * @return true to cancel further event processing and not place features through vanilla's method. false to pass on to further event processing.
+	 * @author Valoeghese
+	 */
+	@FunctionalInterface
+	public interface GenerateFeaturesStart {
+		boolean onStartGenerateFeatures(ChunkGenerator generator, ChunkRegion region, StructureAccessor accessor);
+	}
+
+	/**
+	 * Called on feature placement to allow for mods to modify the chunk without using mojang's "features", among various other things.
+	 * @author Valoeghese
+	 */
+	@FunctionalInterface
+	public interface GenerateFeaturesEnd {
+		void onEndGenerateFeatures(ChunkGenerator generator, ChunkRegion region, StructureAccessor accessor);
+	}
+
+	/**
+	 * Called on chunk generation entity population to allow for mods to spawn entities with their own logic.
+	 * @param spawnPosGetter a function used by vanilla to get the spawn block pos for the given x/z coordinates.
+	 * @author Valoeghese
+	 */
+	@FunctionalInterface
+	public interface PopulateEntities {
+		void onPopulateEntities(ServerWorldAccess world, Biome biome, int chunkX, int chunkZ, Random random, SpawnPosGetter spawnPosGetter);
+	}
 }

src/main/resources/fabric.mod.json

@@ -6,8 +6,10 @@
   "name": "Too Many Events",
   "description": "More events for modders to use",
   "authors": [
-    "Valoeghese",
-	"HalfOf2"
+	"b0undary",
+	"HalfOf2",
+    "LeoCTH",
+    "Valoeghese"
   ],
 
   "license": "MIT",

src/main/resources/toomanyevents.mixins.json

@@ -19,7 +19,8 @@
     "spawn.MixinEntityType",
     "spawn.MixinMobSpawnerLogic",
     "spawn.MixinSpawnHelper",
-    "spawn.MixinSummonCommand"
+    "spawn.MixinSummonCommand",
+    "world.MixinChunkGenerator"
   ],
   "client": [
     "client.MixinBackgroundRenderer",

src/test/java/io/github/fabriccommunity/events/test/ChunkGenTest.java

@@ -0,0 +1,66 @@
+package io.github.fabriccommunity.events.test;
+
+import io.github.fabriccommunity.events.world.WorldGenEvents;
+import net.fabricmc.api.ModInitializer;
+import net.minecraft.block.Blocks;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.SpawnReason;
+import net.minecraft.entity.passive.VillagerEntity;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.biome.Biome;
+
+public class ChunkGenTest implements ModInitializer {
+	public static final boolean ENABLED = true;
+
+	@Override
+	public void onInitialize() {
+		if (ENABLED) {
+			WorldGenEvents.GENERATE_FEATURES_START.register((generator, region, structures) -> {
+				if (random(region.getCenterChunkX(), region.getCenterChunkZ(), (int) region.getSeed(), 0b111) == 0) {
+					return true; // cancel further event processing
+				}
+
+				return false;
+			});
+
+			WorldGenEvents.GENERATE_FEATURES_END.register((generator, region, structures) -> {
+				int x = region.getCenterChunkX() * 16;
+				int z = region.getCenterChunkZ() * 16;
+				BlockPos.Mutable e = new BlockPos.Mutable(x, 0, z);
+
+				for (int y = 128; y >= 32; --y) {
+					e.setY(y);
+					region.setBlockState(e, Blocks.AIR.getDefaultState(), 3);
+				}
+			});
+
+			WorldGenEvents.POPULATE_ENTITIES.register((world, biome, chunkX, chunkZ, random, spawnPosGetter) -> {
+				if (biome.getCategory() != Biome.Category.OCEAN) {
+					int target = random.nextInt(3);
+
+					for (int i = 0; i < target; ++i) {
+						int ex = (chunkX << 4) + random.nextInt(16);
+						int ez = (chunkZ << 4) + random.nextInt(16);
+
+						VillagerEntity villager = EntityType.VILLAGER.create(world.toServerWorld());
+						BlockPos pos = spawnPosGetter.getEntitySpawnPos(world, villager.getType(), ex, ez);
+						villager.refreshPositionAndAngles(pos, random.nextFloat() * 360.0f, 0.0f);
+						villager.headYaw = villager.yaw;
+						villager.bodyYaw = villager.yaw;
+						villager.initialize(world, world.getLocalDifficulty(pos), SpawnReason.STRUCTURE, null, null);
+						world.spawnEntityAndPassengers(villager);
+					}
+				}
+			});
+		}
+	}
+
+	private static int random(int x, int y, int seed, int mask) {
+		seed = 375462423 * seed + 672456235;
+		seed += x;
+		seed = 375462423 * seed + 672456235;
+		seed += y;
+		seed = 375462423 * seed + 672456235;
+		return seed & mask;
+	}
+}

src/test/resources/fabric.mod.json

@@ -17,6 +17,7 @@
     "main": [
       "io.github.fabriccommunity.events.test.BiomePlacementTest",
       "io.github.fabriccommunity.events.test.BlockPlaceTest",
+      "io.github.fabriccommunity.events.test.ChunkGenTest",
       "io.github.fabriccommunity.events.test.FoodTest",
       "io.github.fabriccommunity.events.test.EntitySpawnTest",
       "io.github.fabriccommunity.events.test.PlayerInteractionTest",