implement proper datapack reload+per world height

core/src/main/java/com/volmit/iris/Iris.java

@@ -747,6 +747,9 @@ public class Iris extends VolmitPlugin implements Listener {
             ff.mkdirs();
             service(StudioSVC.class).installIntoWorld(getSender(), dim.getLoadKey(), w.worldFolder());
         }
+        if (!INMS.get().registerDimension(worldName, dim)) {
+            throw new IllegalStateException("Unable to register dimension " + dim.getName());
+        }
 
         return new BukkitChunkGenerator(w, false, ff, dim.getLoadKey(), false);
     }

core/src/main/java/com/volmit/iris/core/ServerConfigurator.java

@@ -228,7 +228,7 @@ public class ServerConfigurator {
             Iris.info( "Hotloading all Datapacks!");
             if (INMS.get().supportsDataPacks()) {
                 for (File folder : getDatapacksFolder()) {
-                    INMS.get().loadDatapack(folder);
+                    INMS.get().loadDatapack(folder, false);
                 }
                 Iris.info("Datapacks Hotloaded!");
                 Iris.info(C.YELLOW + "============================================================================");

core/src/main/java/com/volmit/iris/core/commands/CommandStudio.java

@@ -20,9 +20,11 @@ package com.volmit.iris.core.commands;
 
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.IrisSettings;
+import com.volmit.iris.core.ServerConfigurator;
 import com.volmit.iris.core.gui.NoiseExplorerGUI;
 import com.volmit.iris.core.gui.VisionGUI;
 import com.volmit.iris.core.loader.IrisData;
+import com.volmit.iris.core.nms.INMS;
 import com.volmit.iris.core.project.IrisProject;
 import com.volmit.iris.core.service.ConversionSVC;
 import com.volmit.iris.core.service.StudioSVC;
@@ -279,13 +281,23 @@ public class CommandStudio implements DecreeExecutor {
     }
 
     @Decree(description = "Hotload a studio", aliases = {"reload", "h"})
-    public void hotload() {
+    public void hotload(@Param(defaultValue = "false") boolean reloadDataPack) {
         if (!Iris.service(StudioSVC.class).isProjectOpen()) {
             sender().sendMessage(C.RED + "No studio world open!");
             return;
         }
-        Iris.service(StudioSVC.class).getActiveProject().getActiveProvider().getEngine().hotload();
+        var provider = Iris.service(StudioSVC.class).getActiveProject().getActiveProvider();
+        provider.getEngine().hotload();
         sender().sendMessage(C.GREEN + "Hotloaded");
+        if (reloadDataPack) {
+            var world = provider.getTarget().getWorld().realWorld();
+            if (world == null) {
+                sender().sendMessage(C.RED + "Failed to reload datapacks.");
+                return;
+            }
+            boolean success = INMS.get().loadDatapack(new File(world.getWorldFolder(), "datapacks"), true);
+            sender().sendMessage(success ? C.GREEN + "Reloaded datapacks." : C.RED + "Failed to reload datapacks.");
+        }
     }
 
     @Decree(description = "Show loot if a chest were right here", origin = DecreeOrigin.PLAYER, sync = true)

core/src/main/java/com/volmit/iris/core/nms/INMSBinding.java

@@ -19,6 +19,7 @@
 package com.volmit.iris.core.nms;
 
 import com.volmit.iris.engine.framework.Engine;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
 import com.volmit.iris.util.mantle.Mantle;
@@ -113,7 +114,11 @@ public interface INMSBinding {
     
     Entity spawnEntity(Location location, EntityType type, CreatureSpawnEvent.SpawnReason reason);
 
-    boolean loadDatapack(File datapackFolder);
+    boolean loadDatapack(File datapackFolder, boolean replace);
+
+    default boolean registerDimension(String name, IrisDimension dimension) {
+        return false;
+    }
 
     void injectBukkit();
 }

core/src/main/java/com/volmit/iris/core/nms/v1X/NMSBinding1X.java

@@ -107,7 +107,7 @@ public class NMSBinding1X implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File datapackFolder) {
+    public boolean loadDatapack(File datapackFolder, boolean replace) {
         return false;
     }
 

core/src/main/java/com/volmit/iris/core/tools/IrisWorldCreator.java

@@ -19,6 +19,7 @@
 package com.volmit.iris.core.tools;
 
 import com.volmit.iris.core.loader.IrisData;
+import com.volmit.iris.core.nms.INMS;
 import com.volmit.iris.engine.object.*;
 import com.volmit.iris.engine.platform.BukkitChunkGenerator;
 import org.bukkit.Bukkit;
@@ -84,6 +85,9 @@ public class IrisWorldCreator {
                 ? dim.getLoader().getDataFolder() :
                 new File(w.worldFolder(), "iris/pack"), dimensionName, smartVanillaHeight);
 
+        if (!INMS.get().registerDimension(name, dim)) {
+            throw new IllegalStateException("Unable to register dimension " + dim.getName());
+        }
 
         return new WorldCreator(name)
                 .environment(findEnvironment())

nms/v1_19_R1/src/main/java/com/volmit/iris/core/nms/v1_19_R1/NMSBinding.java

@@ -13,13 +13,19 @@ import java.util.IdentityHashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Vector;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import com.google.common.base.Preconditions;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.io.IO;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
@@ -29,9 +35,14 @@ import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import net.bytebuddy.matcher.ElementMatchers;
 import net.minecraft.core.MappedRegistry;
 import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -45,6 +56,7 @@ import org.bukkit.craftbukkit.v1_19_R1.inventory.CraftItemStack;
 import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -551,25 +563,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registry.DIMENSION_TYPE_REGISTRY);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registry.DIMENSION_TYPE_REGISTRY, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registry.DIMENSION_TYPE_REGISTRY, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -579,7 +600,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registry.BIOME_REGISTRY, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -594,12 +616,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registry.BIOME_REGISTRY).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registry.BIOME_REGISTRY, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -618,29 +653,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registry.DIMENSION_TYPE_REGISTRY, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registry.DIMENSION_TYPE_REGISTRY).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -650,19 +686,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -715,6 +757,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -724,6 +773,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registry.DIMENSION_TYPE_REGISTRY, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registry.DIMENSION_TYPE_REGISTRY).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {

nms/v1_19_R2/src/main/java/com/volmit/iris/core/nms/v1_19_R2/NMSBinding.java

@@ -13,13 +13,19 @@ import java.util.IdentityHashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Vector;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import com.google.common.base.Preconditions;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.io.IO;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
@@ -29,9 +35,14 @@ import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import net.bytebuddy.matcher.ElementMatchers;
 import net.minecraft.core.MappedRegistry;
 import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -45,6 +56,7 @@ import org.bukkit.craftbukkit.v1_19_R2.inventory.CraftItemStack;
 import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -553,25 +565,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registries.DIMENSION_TYPE);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registries.DIMENSION_TYPE, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -581,7 +602,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registries.BIOME, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -596,12 +618,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registries.BIOME).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registries.BIOME, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -620,29 +655,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registries.DIMENSION_TYPE, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registries.DIMENSION_TYPE).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -652,19 +688,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -716,6 +758,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -725,6 +774,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registries.DIMENSION_TYPE).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {

nms/v1_19_R3/src/main/java/com/volmit/iris/core/nms/v1_19_R3/NMSBinding.java

@@ -13,13 +13,19 @@ import java.util.IdentityHashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Vector;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import com.google.common.base.Preconditions;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.io.IO;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
@@ -29,9 +35,14 @@ import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import net.bytebuddy.matcher.ElementMatchers;
 import net.minecraft.core.MappedRegistry;
 import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -45,6 +56,7 @@ import org.bukkit.craftbukkit.v1_19_R3.inventory.CraftItemStack;
 import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -557,25 +569,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registries.DIMENSION_TYPE);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registries.DIMENSION_TYPE, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -585,7 +606,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registries.BIOME, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -600,12 +622,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registries.BIOME).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registries.BIOME, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -624,29 +659,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registries.DIMENSION_TYPE, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registries.DIMENSION_TYPE).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -656,19 +692,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -720,6 +762,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -729,6 +778,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registries.DIMENSION_TYPE).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {

nms/v1_20_R1/src/main/java/com/volmit/iris/core/nms/v1_20_R1/NMSBinding.java

@@ -1,14 +1,18 @@
 package com.volmit.iris.core.nms.v1_20_R1;
 
 import com.google.common.base.Preconditions;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.nms.INMSBinding;
 import com.volmit.iris.engine.data.cache.AtomicCache;
 import com.volmit.iris.engine.framework.Engine;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
 import com.volmit.iris.util.format.C;
@@ -38,8 +42,11 @@ import net.minecraft.nbt.NbtIo;
 import net.minecraft.nbt.TagParser;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.level.ServerLevel;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
+import net.minecraft.world.RandomSequences;
 import net.minecraft.world.entity.EntityDimensions;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.biome.BiomeSource;
@@ -50,6 +57,9 @@ import net.minecraft.world.level.chunk.ChunkAccess;
 import net.minecraft.world.level.chunk.ChunkStatus;
 import net.minecraft.world.level.chunk.LevelChunk;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -66,6 +76,7 @@ import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.event.entity.CreatureSpawnEvent;
 import org.bukkit.entity.EntityType;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -84,7 +95,9 @@ import java.util.IdentityHashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Vector;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 
 public class NMSBinding implements INMSBinding {
@@ -543,25 +556,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registries.DIMENSION_TYPE);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registries.DIMENSION_TYPE, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -571,7 +593,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registries.BIOME, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -586,12 +609,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registries.BIOME).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registries.BIOME, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -610,29 +646,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registries.DIMENSION_TYPE, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registries.DIMENSION_TYPE).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -642,19 +679,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -719,6 +762,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, RandomSequences.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -728,6 +778,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registries.DIMENSION_TYPE).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {

nms/v1_20_R2/src/main/java/com/volmit/iris/core/nms/v1_20_R2/NMSBinding.java

@@ -13,13 +13,19 @@ import java.util.IdentityHashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Vector;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import com.google.common.base.Preconditions;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.io.IO;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
@@ -28,9 +34,15 @@ import net.bytebuddy.asm.Advice;
 import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import net.bytebuddy.matcher.ElementMatchers;
 import net.minecraft.core.MappedRegistry;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
+import net.minecraft.world.RandomSequences;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -44,6 +56,7 @@ import org.bukkit.craftbukkit.v1_20_R2.util.CraftNamespacedKey;
 import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -553,25 +566,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registries.DIMENSION_TYPE);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registries.DIMENSION_TYPE, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -581,7 +603,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registries.BIOME, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -596,12 +619,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registries.BIOME).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registries.BIOME, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -620,29 +656,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registries.DIMENSION_TYPE, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registries.DIMENSION_TYPE).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -652,19 +689,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -721,6 +764,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, RandomSequences.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -730,6 +780,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registries.DIMENSION_TYPE).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {

nms/v1_20_R3/src/main/java/com/volmit/iris/core/nms/v1_20_R3/NMSBinding.java

@@ -6,27 +6,54 @@ import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.File;
 import java.io.FilenameFilter;
+import java.io.IOException;
+import java.lang.instrument.ClassFileTransformer;
+import java.lang.instrument.Instrumentation;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
+import java.nio.file.Files;
 import java.util.*;
+import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.logging.Logger;
 
 import com.google.common.base.Preconditions;
+import com.google.common.base.Supplier;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonNull;
+import com.google.gson.JsonObject;
 import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
 import com.mojang.serialization.JsonOps;
 import com.mojang.serialization.Lifecycle;
+import com.volmit.iris.engine.object.IrisDimension;
 import com.volmit.iris.util.format.C;
+import com.volmit.iris.util.function.NastySupplier;
 import com.volmit.iris.util.io.IO;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
 import net.bytebuddy.ByteBuddy;
+import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.asm.Advice;
+import net.bytebuddy.description.type.TypeDescription;
+import net.bytebuddy.dynamic.DynamicType;
 import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
 import net.bytebuddy.matcher.ElementMatchers;
+import net.bytebuddy.utility.JavaModule;
+import net.minecraft.core.IdMapper;
 import net.minecraft.core.MappedRegistry;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.progress.ChunkProgressListener;
 import net.minecraft.util.GsonHelper;
+import net.minecraft.util.worldupdate.WorldUpgrader;
+import net.minecraft.world.RandomSequences;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.level.LevelAccessor;
+import net.minecraft.world.level.LevelHeightAccessor;
 import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.PrimaryLevelData;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -40,6 +67,7 @@ import org.bukkit.craftbukkit.v1_20_R3.util.CraftNamespacedKey;
 import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -445,13 +473,13 @@ public class NMSBinding implements INMSBinding {
     @Override
     public MCAPaletteAccess createPalette() {
         MCAIdMapper<BlockState> registry = registryCache.aquireNasty(() -> {
-            Field cf = net.minecraft.core.IdMapper.class.getDeclaredField("tToId");
+            Field cf = IdMapper.class.getDeclaredField("tToId");
-            Field df = net.minecraft.core.IdMapper.class.getDeclaredField("idToT");
+            Field df = IdMapper.class.getDeclaredField("idToT");
-            Field bf = net.minecraft.core.IdMapper.class.getDeclaredField("nextId");
+            Field bf = IdMapper.class.getDeclaredField("nextId");
             cf.setAccessible(true);
             df.setAccessible(true);
             bf.setAccessible(true);
-            net.minecraft.core.IdMapper<BlockState> blockData = Block.BLOCK_STATE_REGISTRY;
+            IdMapper<BlockState> blockData = Block.BLOCK_STATE_REGISTRY;
             int b = bf.getInt(blockData);
             Object2IntMap<BlockState> c = (Object2IntMap<BlockState>) cf.get(blockData);
             List<BlockState> d = (List<BlockState>) df.get(blockData);
@@ -551,25 +579,34 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
-    public boolean loadDatapack(File folder) {
+    public boolean registerDimension(String name, IrisDimension dimension) {
+        var registry = registry(Registries.DIMENSION_TYPE);
+        var baseLocation = switch (dimension.getEnvironment()) {
+            case NORMAL -> new ResourceLocation("minecraft", "overworld");
+            case NETHER -> new ResourceLocation("minecraft", "the_nether");
+            case THE_END -> new ResourceLocation("minecraft", "the_end");
+            case CUSTOM -> throw new IllegalArgumentException("Cannot register custom dimension");
+        };
+        var base = registry.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, baseLocation)).orElse(null);
+        if (base == null) return false;
+        var json = encode(DimensionType.CODEC, base).orElse(null);
+        if (json == null) return false;
+        var object = json.getAsJsonObject();
+        var height = dimension.getDimensionHeight();
+        object.addProperty("min_y", height.getMin());
+        object.addProperty("height", height.getMax() - height.getMin());
+        object.addProperty("logical_height", dimension.getLogicalHeight());
+        var value = decode(DimensionType.CODEC, object.toString()).map(Holder::value).orElse(null);
+        if (value == null) return false;
+        return register(Registries.DIMENSION_TYPE, new ResourceLocation("iris", name), value, true);
+    }
+
+    @Override
+    public boolean loadDatapack(File folder, boolean replace) {
         var data = new File(folder, "iris/data");
         if (!data.exists() || !data.isDirectory()) return false;
         FilenameFilter jsonFilter = (dir, name) -> new File(dir, name).isFile() && name.toLowerCase().endsWith(".json");
 
-        var dimensionFolder = new File(data, "minecraft/dimension_type");
-        if (dimensionFolder.exists()) {
-            var files = dimensionFolder.listFiles(jsonFilter);
-            if (files != null) {
-                for (File file : files) {
-                    try {
-                        modifyDimension(file);
-                    } catch (Throwable e) {
-                        Iris.error("Unable to modify dimension!");
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
         var files = data.listFiles((dir, name) -> new File(dir, name).isDirectory());
         if (files == null) return false;
         for (File file : files) {
@@ -579,7 +616,8 @@ public class NMSBinding implements INMSBinding {
             if (biomeFiles == null) continue;
             for (File biomeFile : biomeFiles) {
                 try {
-                    registerBiome(file.getName(), biomeFile);
+                    var value = decode(net.minecraft.world.level.biome.Biome.CODEC, IO.readAll(file)).map(Holder::value).orElse(null);
+                    register(Registries.BIOME, from(file.getName(), biomeFile), value, replace);
                 } catch (Throwable e) {
                     Iris.error("Failed to register biome " + file.getName() + ":" + biomeFile.getName());
                     e.printStackTrace();
@@ -594,12 +632,25 @@ public class NMSBinding implements INMSBinding {
         return new ResourceLocation(namespace, name.substring(0, name.lastIndexOf('.')));
     }
 
-    private void registerBiome(String namespace, File file) throws Throwable {
+    private <T> Optional<T> decode(Codec<T> codec, String json) {
-        var rawRegistry = registry().registry(Registries.BIOME).orElse(null);
+        return codec.decode(JsonOps.INSTANCE, GsonHelper.parse(json)).get().left().map(Pair::getFirst);
-        var key = ResourceKey.create(Registries.BIOME, from(namespace, file));
+    }
-        if (!(rawRegistry instanceof MappedRegistry<net.minecraft.world.level.biome.Biome> registry))
+
-            throw new IllegalStateException("The Biome Registry is not a mapped Registry!");
+    private <T> Optional<JsonElement> encode(Codec<T> codec, T value) {
-        if (registry.containsKey(key)) return;
+        return codec.encode(value, JsonOps.INSTANCE, new JsonObject()).result();
+    }
+
+    private <T> boolean register(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value, boolean replace) {
+        Preconditions.checkArgument(registryKey != null, "The registry cannot be null!");
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
+        var registry = registry(registryKey);
+        var key = ResourceKey.create(registryKey, location);
+        try {
+            if (registry.containsKey(key)) {
+                if (!replace) return false;
+                return replace(registryKey, location, value);
+            }
             Field field = getField(MappedRegistry.class, boolean.class);
             field.setAccessible(true);
             boolean frozen = field.getBoolean(registry);
@@ -618,29 +669,30 @@ public class NMSBinding implements INMSBinding {
             }
 
             try {
-            var biome = net.minecraft.world.level.biome.Biome.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+                registry.createIntrusiveHolder(value);
-                    .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+                registry.register(key, value, Lifecycle.stable());
-            if (biome == null)
+                return true;
-                throw new IllegalStateException("Failed to decode biome " + file.getName());
-
-            registry.createIntrusiveHolder(biome);
-            registry.register(key, biome, Lifecycle.stable());
             } finally {
                 field.setBoolean(registry, frozen);
                 if (holders) {
                     holdersField.set(registry, null);
                 }
             }
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @SuppressWarnings("unchecked")
-    private void modifyDimension(File file) throws Throwable {
+    private <T> boolean replace(ResourceKey<Registry<T>> registryKey, ResourceLocation location, T value) {
-        var key = ResourceKey.create(Registries.DIMENSION_TYPE, from("minecraft", file));
+        Preconditions.checkArgument(registryKey != null, "The registryKey cannot be null!");
-        var rawRegistry = registry().registry(Registries.DIMENSION_TYPE).orElse(null);
+        Preconditions.checkArgument(location != null, "The location cannot be null!");
-        if (!(rawRegistry instanceof MappedRegistry<DimensionType> registry))
+        Preconditions.checkArgument(value != null, "The value cannot be null!");
-            throw new IllegalStateException("The Dimension Registry is not a mapped Registry!");
+        var registry = registry(registryKey);
-
+        var key = ResourceKey.create(registryKey, location);
-        var holder = registry.getHolder(key).orElseThrow(() -> new IllegalStateException("Unknown dimension type: " + key));
+        try {
+            var holder = registry.getHolder(key).orElse(null);
+            if (holder == null) return false;
             var oldValue = holder.value();
             Field valueField = getField(Holder.Reference.class, "T");
             valueField.setAccessible(true);
@@ -650,19 +702,25 @@ public class NMSBinding implements INMSBinding {
             byValueField.setAccessible(true);
             Field lifecyclesField = getField(MappedRegistry.class, buildType(Map.class, "T", Lifecycle.class.getName()));
             lifecyclesField.setAccessible(true);
-        var toId = (Reference2IntMap<DimensionType>) toIdField.get(registry);
+            var toId = (Reference2IntMap<T>) toIdField.get(registry);
-        var byValue = (Map<DimensionType, Holder.Reference<DimensionType>>) byValueField.get(registry);
+            var byValue = (Map<T, Holder.Reference<T>>) byValueField.get(registry);
-        var lifecycles = (Map<DimensionType, Lifecycle>) lifecyclesField.get(registry);
+            var lifecycles = (Map<T, Lifecycle>) lifecyclesField.get(registry);
 
-        var newValue = DimensionType.CODEC.decode(JsonOps.INSTANCE, GsonHelper.parse(IO.readAll(file)))
+            valueField.set(holder, value);
-                .get().left().map(Pair::getFirst).map(Holder::value).orElse(null);
+            toId.put(value, toId.removeInt(oldValue));
-        if (newValue == null)
+            byValue.put(value, byValue.remove(oldValue));
-            throw new IllegalArgumentException("Failed to parse dimension type " + key.location() + " from " + file);
+            lifecycles.put(value, lifecycles.remove(oldValue));
+            return true;
+        } catch (Throwable e) {
+            throw new IllegalStateException(e);
+        }
+    }
 
-        valueField.set(holder, newValue);
+    private <T> MappedRegistry<T> registry(ResourceKey<Registry<T>> registryKey) {
-        toId.put(newValue, toId.removeInt(oldValue));
+        var rawRegistry = registry().registry(registryKey).orElse(null);
-        byValue.put(newValue, byValue.remove(oldValue));
+        if (!(rawRegistry instanceof MappedRegistry<T> registry))
-        lifecycles.put(newValue, lifecycles.remove(oldValue));
+            throw new IllegalStateException("The Registry is not a mapped Registry!");
+        return registry;
     }
 
     private static String buildType(Class<?> clazz, String... parameterTypes) {
@@ -718,6 +776,13 @@ public class NMSBinding implements INMSBinding {
                     .visit(Advice.to(WorldCreatorAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(String.class))))
                     .make()
                     .load(WorldCreator.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
+            new ByteBuddy()
+                    .redefine(ServerLevel.class)
+                    .visit(Advice.to(ServerLevelAdvice.class).on(ElementMatchers.isConstructor().and(ElementMatchers.takesArguments(MinecraftServer.class, Executor.class, LevelStorageSource.LevelStorageAccess.class,
+                            PrimaryLevelData.class, ResourceKey.class, LevelStem.class, ChunkProgressListener.class, boolean.class, long.class,
+                            List.class, boolean.class, RandomSequences.class, World.Environment.class, ChunkGenerator.class, BiomeProvider.class))))
+                    .make()
+                    .load(ServerLevel.class.getClassLoader(), ClassReloadingStrategy.fromInstalledAgent());
             Iris.info("Injected Bukkit Successfully!");
         } catch (Exception e) {
             Iris.info(C.RED + "Failed to Inject Bukkit!");
@@ -727,6 +792,28 @@ public class NMSBinding implements INMSBinding {
 
     }
 
+    private static class ServerLevelAdvice {
+        @Advice.OnMethodEnter
+        static void enter(@Advice.Argument(0) MinecraftServer server, @Advice.Argument(2) LevelStorageSource.LevelStorageAccess access, @Advice.Argument(4) ResourceKey<Level> key, @Advice.Argument(value = 5, readOnly = false) LevelStem levelStem) {
+            File iris = new File(access.levelDirectory.path().toFile(), "iris");
+            if (!iris.exists()) return;
+            var logger = MinecraftServer.LOGGER;
+            ResourceKey<DimensionType> typeKey = ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()));
+            RegistryAccess registryAccess = server.registryAccess();
+            Registry<DimensionType> registry = registryAccess.registry(Registries.DIMENSION_TYPE).orElse(null);
+            if (registry == null) {
+                logger.warn("Unable to find registry for dimension type {}", typeKey);
+                return;
+            }
+            Holder<DimensionType> holder = registry.getHolder(typeKey).orElse(null);
+            if (holder == null) {
+                logger.warn("Unable to find dimension type {}", typeKey);
+                return;
+            }
+            levelStem = new LevelStem(holder, levelStem.generator());
+        }
+    }
+
     private static class WorldCreatorAdvice {
         @Advice.OnMethodEnter
         static void enter(@Advice.Argument(0) String name) {