v+

3.6.6

build.gradle

@@ -1,3 +1,5 @@
+import xyz.jpenilla.runpaper.task.RunServer
+
 /*
  * Iris is a World Generator for Minecraft Bukkit Servers
  * Copyright (c) 2021 Arcane Arts (Volmit Software)
@@ -30,10 +32,11 @@ plugins {
     id 'java-library'
     id "io.github.goooler.shadow" version "8.1.7"
     id "de.undercouch.download" version "5.0.1"
+    id "xyz.jpenilla.run-paper" version "2.3.1"
 }
 
 
-version '3.6.4-1.20.1-1.21.4'
+version '3.6.6-1.20.1-1.21.4'
 
 // ADD YOURSELF AS A NEW LINE IF YOU WANT YOUR OWN BUILD TASK GENERATED
 // ======================== WINDOWS =============================
@@ -53,6 +56,11 @@ registerCustomOutputTaskUnix('PixelMac', '/Users/test/Desktop/mcserver/plugins')
 registerCustomOutputTaskUnix('CrazyDev22LT', '/home/julian/Desktop/server/plugins')
 // ==============================================================
 
+def MIN_HEAP_SIZE = "2G"
+def MAX_HEAP_SIZE = "8G"
+//Valid values are: none, truecolor, indexed256, indexed16, indexed8
+def COLOR = "truecolor"
+
 def NMS_BINDINGS = Map.of(
         "v1_21_R3", "1.21.4-R0.1-SNAPSHOT",
         "v1_21_R2", "1.21.3-R0.1-SNAPSHOT",
@@ -62,21 +70,34 @@ def NMS_BINDINGS = Map.of(
         "v1_20_R2", "1.20.2-R0.1-SNAPSHOT",
         "v1_20_R1", "1.20.1-R0.1-SNAPSHOT",
 )
-def JVM_VERSION = Map.of()
-NMS_BINDINGS.each { nms ->
-    project(":nms:${nms.key}") {
+def JVM_VERSION = Map.<String, Integer>of()
+NMS_BINDINGS.forEach { key, value ->
+    project(":nms:$key") {
         apply plugin: 'java'
         apply plugin: 'com.volmit.nmstools'
 
         nmsTools {
-            it.jvm = JVM_VERSION.getOrDefault(nms.key, 21)
-            it.version = nms.value
+            it.jvm = JVM_VERSION.getOrDefault(key, 21)
+            it.version = value
         }
 
         dependencies {
             implementation project(":core")
         }
     }
+
+    tasks.register("runServer-$key", RunServer) {
+        group("servers")
+        minecraftVersion(value.split("-")[0])
+        minHeapSize(MIN_HEAP_SIZE)
+        maxHeapSize(MAX_HEAP_SIZE)
+        pluginJars(tasks.shadowJar.archiveFile)
+        javaLauncher = javaToolchains.launcherFor { it.languageVersion = JavaLanguageVersion.of(JVM_VERSION.getOrDefault(key, 21))}
+        runDirectory.convention(layout.buildDirectory.dir("run/$key"))
+        systemProperty("disable.watchdog", "")
+        systemProperty("net.kyori.ansi.colorLevel", COLOR)
+        systemProperty("com.mojang.eula.agree", true)
+    }
 }
 
 shadowJar {

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

@@ -459,15 +459,17 @@ public class Iris extends VolmitPlugin implements Listener {
         initialize("com.volmit.iris.core.service").forEach((i) -> services.put((Class<? extends IrisService>) i.getClass(), (IrisService) i));
         INMS.get();
         IO.delete(new File("iris"));
+        compat = IrisCompat.configured(getDataFile("compat.json"));
+        ServerConfigurator.configure();
+        new IrisContextInjector();
         IrisSafeguard.IrisSafeguardSystem();
         getSender().setTag(getTag());
-        compat = IrisCompat.configured(getDataFile("compat.json"));
+        IrisSafeguard.earlySplash();
         linkMultiverseCore = new MultiverseCoreLink();
         linkMythicMobs = new MythicMobsLink();
         configWatcher = new FileWatcher(getDataFile("settings.json"));
         services.values().forEach(IrisService::onEnable);
         services.values().forEach(this::registerListener);
-        registerListener(new IrisContextInjector());
         J.s(() -> {
             J.a(() -> PaperLib.suggestPaper(this));
             J.a(() -> IO.delete(getTemp()));

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

@@ -31,6 +31,7 @@ import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
 import com.volmit.iris.util.collection.KSet;
 import com.volmit.iris.util.format.C;
+import com.volmit.iris.util.misc.ServerProperties;
 import com.volmit.iris.util.plugin.VolmitSender;
 import com.volmit.iris.util.scheduling.J;
 import lombok.Data;
@@ -97,6 +98,7 @@ public class ServerConfigurator {
         }
         KList<File> worlds = new KList<>();
         Bukkit.getServer().getWorlds().forEach(w -> worlds.add(new File(w.getWorldFolder(), "datapacks")));
+        if (worlds.isEmpty()) worlds.add(new File(Bukkit.getWorldContainer(), ServerProperties.LEVEL_NAME + "/datapacks"));
         return worlds;
     }
 

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

@@ -140,7 +140,7 @@ public class CommandDeveloper implements DecreeExecutor {
     public void packBenchmark(
             @Param(description = "The pack to bench", aliases = {"pack"}, defaultValue = "overworld")
             IrisDimension dimension,
-            @Param(description = "Radius in regions", defaultValue = "5")
+            @Param(description = "Radius in regions", defaultValue = "2048")
             int radius,
             @Param(description = "Open GUI while benchmarking", defaultValue = "false")
             boolean gui

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

@@ -19,9 +19,7 @@
 package com.volmit.iris.core.commands;
 
 import com.volmit.iris.Iris;
-import com.volmit.iris.core.IrisSettings;
 import com.volmit.iris.core.gui.PregeneratorJob;
-import com.volmit.iris.core.pregenerator.LazyPregenerator;
 import com.volmit.iris.core.pregenerator.PregenTask;
 import com.volmit.iris.core.tools.IrisToolbelt;
 import com.volmit.iris.util.decree.DecreeExecutor;
@@ -29,12 +27,9 @@ import com.volmit.iris.util.decree.annotations.Decree;
 import com.volmit.iris.util.decree.annotations.Param;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.math.Position2;
-import org.bukkit.Bukkit;
 import org.bukkit.World;
 import org.bukkit.util.Vector;
 
-import java.io.File;
-
 @Decree(name = "pregen", aliases = "pregenerate", description = "Pregenerate your Iris worlds!")
 public class CommandPregen implements DecreeExecutor {
     @Decree(description = "Pregenerate a world")
@@ -52,13 +47,12 @@ public class CommandPregen implements DecreeExecutor {
                 sender().sendMessage(C.RED + "Please make sure the world is loaded & the engine is initialized. Generate a new chunk, for example.");
             }
             radius = Math.max(radius, 1024);
-            int w = (radius >> 9 + 1) * 2;
             IrisToolbelt.pregenerate(PregenTask
                     .builder()
-                    .center(new Position2(center.getBlockX() >> 9, center.getBlockZ() >> 9))
+                    .center(new Position2(center.getBlockX(), center.getBlockZ()))
                     .gui(true)
-                    .width(w)
-                    .height(w)
+                    .radiusX(radius)
+                    .radiusZ(radius)
                     .build(), world);
             String msg = C.GREEN + "Pregen started in " + C.GOLD + world.getName() + C.GREEN + " of " + C.GOLD + (radius * 2) + C.GREEN + " by " + C.GOLD + (radius * 2) + C.GREEN + " blocks from " + C.GOLD + center.getX() + "," + center.getZ();
             sender().sendMessage(msg);

core/src/main/java/com/volmit/iris/core/gui/PregeneratorJob.java

@@ -24,7 +24,6 @@ import com.volmit.iris.core.pregenerator.IrisPregenerator;
 import com.volmit.iris.core.pregenerator.PregenListener;
 import com.volmit.iris.core.pregenerator.PregenTask;
 import com.volmit.iris.core.pregenerator.PregeneratorMethod;
-import com.volmit.iris.core.tools.IrisPackBenchmarking;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.format.Form;
@@ -45,8 +44,6 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Consumer;
 
-import static com.volmit.iris.core.tools.IrisPackBenchmarking.benchmarkInProgress;
-
 public class PregeneratorJob implements PregenListener {
     private static final Color COLOR_EXISTS = parseColor("#4d7d5b");
     private static final Color COLOR_BLACK = parseColor("#4d7d5b");
@@ -81,12 +78,12 @@ public class PregeneratorJob implements PregenListener {
         this.task = task;
         this.pregenerator = new IrisPregenerator(task, method, this);
         max = new Position2(0, 0);
-        min = new Position2(0, 0);
-        task.iterateRegions((xx, zz) -> {
-            min.setX(Math.min(xx << 5, min.getX()));
-            min.setZ(Math.min(zz << 5, min.getZ()));
-            max.setX(Math.max((xx << 5) + 31, max.getX()));
-            max.setZ(Math.max((zz << 5) + 31, max.getZ()));
+        min = new Position2(Integer.MAX_VALUE, Integer.MAX_VALUE);
+        task.iterateAllChunks((xx, zz) -> {
+            min.setX(Math.min(xx, min.getX()));
+            min.setZ(Math.min(zz, min.getZ()));
+            max.setX(Math.max(xx, max.getX()));
+            max.setZ(Math.max(zz, max.getZ()));
         });
 
         if (IrisSettings.get().getGui().isUseServerLaunchedGuis() && task.isGui()) {
@@ -162,7 +159,7 @@ public class PregeneratorJob implements PregenListener {
     }
 
     public void drawRegion(int x, int z, Color color) {
-        J.a(() -> PregenTask.iterateRegion(x, z, (xx, zz) -> {
+        J.a(() -> task.iterateChunks(x, z, (xx, zz) -> {
             draw(xx, zz, color);
             J.sleep(3);
         }));

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

@@ -37,7 +37,7 @@ public class INMS {
             "1.21.4", "v1_21_R3"
     );
     private static final List<Version> PACKS = List.of(
-            new Version(21, 4, "31010"),
+            new Version(21, 4, "31020"),
             new Version(21, 2, "31000"),
             new Version(20, 1, "3910")
     );

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

@@ -20,7 +20,6 @@ package com.volmit.iris.core.nms;
 
 import com.volmit.iris.core.nms.container.AutoClosing;
 import com.volmit.iris.core.nms.container.BiomeColor;
-import com.volmit.iris.core.nms.container.Pair;
 import com.volmit.iris.core.nms.datapack.DataVersion;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.util.collection.KList;
@@ -32,15 +31,12 @@ import com.volmit.iris.util.nbt.mca.palette.MCAPaletteAccess;
 import com.volmit.iris.util.nbt.tag.CompoundTag;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
-import org.bukkit.entity.Dolphin;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.event.entity.CreatureSpawnEvent;
 import org.bukkit.generator.ChunkGenerator;
-import org.bukkit.generator.structure.Structure;
 import org.bukkit.inventory.ItemStack;
 
-import java.awt.*;
 import java.awt.Color;
 
 public interface INMSBinding {
@@ -93,7 +89,11 @@ public interface INMSBinding {
     MCABiomeContainer newBiomeContainer(int min, int max);
 
     default World createWorld(WorldCreator c) {
+        if (missingDimensionTypes(true, true, true))
+            throw new IllegalStateException("Missing dimenstion types to create world");
+
         try (var ignored = injectLevelStems()) {
+            ignored.storeContext();
             return c.createWorld();
         }
     }
@@ -130,11 +130,13 @@ public interface INMSBinding {
 
     KList<String> getStructureKeys();
 
-    default AutoClosing injectLevelStems() {
-        return new AutoClosing(() -> {});
+    AutoClosing injectLevelStems();
+
+    default AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        return null;
     }
 
-    default Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        return new Pair<>(0, injectLevelStems());
-    }
+    boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end);
+
+    void removeCustomDimensions(World world);
 }

core/src/main/java/com/volmit/iris/core/nms/container/AutoClosing.java

@@ -1,5 +1,6 @@
 package com.volmit.iris.core.nms.container;
 
+import com.volmit.iris.util.collection.KMap;
 import com.volmit.iris.util.function.NastyRunnable;
 import lombok.AllArgsConstructor;
 
@@ -7,6 +8,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 @AllArgsConstructor
 public class AutoClosing implements AutoCloseable {
+    private static final KMap<Thread, AutoClosing> CONTEXTS = new KMap<>();
     private final AtomicBoolean closed = new AtomicBoolean();
     private final NastyRunnable action;
 
@@ -14,9 +16,24 @@ public class AutoClosing implements AutoCloseable {
     public void close() {
         if (closed.getAndSet(true)) return;
         try {
+            removeContext();
             action.run();
         } catch (Throwable e) {
             throw new RuntimeException(e);
         }
     }
+
+    public void storeContext() {
+        CONTEXTS.put(Thread.currentThread(), this);
+    }
+
+    public void removeContext() {
+        CONTEXTS.values().removeIf(c -> c == this);
+    }
+
+    public static void closeContext() {
+        AutoClosing closing = CONTEXTS.remove(Thread.currentThread());
+        if (closing == null) return;
+        closing.close();
+    }
 }

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

@@ -20,7 +20,9 @@ package com.volmit.iris.core.nms.v1X;
 
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.nms.INMSBinding;
+import com.volmit.iris.core.nms.container.AutoClosing;
 import com.volmit.iris.core.nms.container.BiomeColor;
+import com.volmit.iris.core.nms.container.Pair;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
@@ -118,6 +120,26 @@ public class NMSBinding1X implements INMSBinding {
         return new KList<>(list);
     }
 
+    @Override
+    public AutoClosing injectLevelStems() {
+        return new AutoClosing(() -> {});
+    }
+
+    @Override
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        return injectLevelStems();
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        return false;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+
+    }
+
     @Override
     public CompoundTag serializeEntity(Entity location) {
         return null;

core/src/main/java/com/volmit/iris/core/pregenerator/ChunkUpdater.java

@@ -165,8 +165,11 @@ public class ChunkUpdater {
             if (rX < dimensions.min.getX() || rX > dimensions.max.getX() || rZ < dimensions.min.getZ() || rZ > dimensions.max.getZ()) {
                 return;
             }
+            if (!new File(world.getWorldFolder(), "region" + File.separator + rX + "." + rZ + ".mca").exists()) {
+                return;
+            }
 
-            PregenTask.iterateRegion(rX, rZ, (x, z) -> {
+            task.iterateChunks(rX, rZ, (x, z) -> {
                 while (paused.get() && !cancelled.get()) {
                     J.sleep(50);
                 }
@@ -348,8 +351,8 @@ public class ChunkUpdater {
         int width = maxZ - minZ + 1;
 
         return new Dimensions(new Position2(minX, minZ), new Position2(maxX, maxZ), height * width, PregenTask.builder()
-                .width((int) Math.ceil(width / 2d))
-                .height((int) Math.ceil(height / 2d))
+                .radiusZ((int) Math.ceil(width / 2d * 512))
+                .radiusX((int) Math.ceil(height / 2d * 512))
                 .center(new Position2(oX, oZ))
                 .build());
     }

core/src/main/java/com/volmit/iris/core/pregenerator/IrisPregenerator.java

@@ -19,7 +19,6 @@
 package com.volmit.iris.core.pregenerator;
 
 import com.volmit.iris.Iris;
-import com.volmit.iris.core.pack.IrisPack;
 import com.volmit.iris.core.tools.IrisPackBenchmarking;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KSet;
@@ -83,7 +82,7 @@ public class IrisPregenerator {
         generatedLast = new AtomicInteger(0);
         generatedLastMinute = new AtomicInteger(0);
         totalChunks = new AtomicInteger(0);
-        task.iterateRegions((_a, _b) -> totalChunks.addAndGet(1024));
+        task.iterateAllChunks((_a, _b) -> totalChunks.incrementAndGet());
         startTime = new AtomicLong(M.ms());
         ticker = new Looper() {
             @Override
@@ -194,7 +193,7 @@ public class IrisPregenerator {
         } else if (!regions) {
             hit = true;
             listener.onRegionGenerating(x, z);
-            PregenTask.iterateRegion(x, z, (xx, zz) -> {
+            task.iterateChunks(x, z, (xx, zz) -> {
                 while (paused.get() && !shutdown.get()) {
                     J.sleep(50);
                 }

core/src/main/java/com/volmit/iris/core/pregenerator/PregenTask.java

@@ -32,17 +32,26 @@ import java.util.Comparator;
 @Data
 public class PregenTask {
     private static final Position2 ZERO = new Position2(0, 0);
-    private static final KList<Position2> ORDER_CENTER = computeChunkOrder();
     private static final KMap<Position2, KList<Position2>> ORDERS = new KMap<>();
 
     @Builder.Default
-    private boolean gui = false;
+    private final boolean gui = false;
     @Builder.Default
-    private Position2 center = new Position2(0, 0);
+    private final Position2 center = new Position2(0, 0);
     @Builder.Default
-    private int width = 1;
+    private final int radiusX = 1;
     @Builder.Default
-    private int height = 1;
+    private final int radiusZ = 1;
+
+    private final Bounds bounds = new Bounds();
+
+    protected PregenTask(boolean gui, Position2 center, int radiusX, int radiusZ) {
+        this.gui = gui;
+        this.center = new ProxiedPos(center);
+        this.radiusX = radiusX;
+        this.radiusZ = radiusZ;
+        bounds.update();
+    }
 
     public static void iterateRegion(int xr, int zr, Spiraled s, Position2 pull) {
         for (Position2 i : ORDERS.computeIfAbsent(pull, PregenTask::computeOrder)) {
@@ -70,29 +79,72 @@ public class PregenTask {
         return p;
     }
 
-    private static KList<Position2> computeChunkOrder() {
-        Position2 center = new Position2(15, 15);
-        KList<Position2> p = new KList<>();
-        new Spiraler(33, 33, (x, z) -> {
-            int xx = x + 15;
-            int zz = z + 15;
-            if (xx < 0 || xx > 31 || zz < 0 || zz > 31) {
-                return;
-            }
-
-            p.add(new Position2(xx, zz));
-        }).drain();
-        p.sort(Comparator.comparing((i) -> i.distance(center)));
-        return p;
+    public void iterateRegions(Spiraled s) {
+        var bound = bounds.region();
+        new Spiraler(bound.sizeX, bound.sizeZ, ((x, z) -> {
+            if (bound.check(x, z)) s.on(x, z);
+        })).setOffset(center.getX() >> 9, center.getZ() >> 9).drain();
     }
 
-    public void iterateRegions(Spiraled s) {
-        new Spiraler(getWidth() * 2, getHeight() * 2, s)
-                .setOffset(center.getX(), center.getZ()).drain();
+    public void iterateChunks(int rX, int rZ, Spiraled s) {
+        var bound = bounds.chunk();
+        iterateRegion(rX, rZ, ((x, z) -> {
+            if (bound.check(x, z)) s.on(x, z);
+        }));
     }
 
     public void iterateAllChunks(Spiraled s) {
-        new Spiraler(getWidth() * 2, getHeight() * 2, (x, z) -> iterateRegion(x, z, s))
-                .setOffset(center.getX(), center.getZ()).drain();
+        iterateRegions(((rX, rZ) -> iterateChunks(rX, rZ, s)));
+    }
+
+    private class Bounds {
+        private Bound chunk = null;
+        private Bound region = null;
+
+        public void update() {
+            int maxX = center.getX() + radiusX;
+            int maxZ = center.getZ() + radiusZ;
+            int minX = center.getX() - radiusX;
+            int minZ = center.getZ() - radiusZ;
+
+            chunk = new Bound(minX >> 4, minZ >> 4, Math.ceilDiv(maxX, 16), Math.ceilDiv(maxZ, 16));
+            region = new Bound(minX >> 9, minZ >> 9, Math.ceilDiv(maxX, 512), Math.ceilDiv(maxZ, 512));
+        }
+
+        public Bound chunk() {
+            if (chunk == null) update();
+            return chunk;
+        }
+
+        public Bound region() {
+            if (region == null) update();
+            return region;
+        }
+    }
+
+    private record Bound(int minX, int maxX, int minZ, int maxZ, int sizeX, int sizeZ) {
+        private Bound(int minX, int minZ, int maxX, int maxZ) {
+            this(minX, maxX, minZ, maxZ, maxZ - minZ + 1, maxZ - minZ + 1);
+        }
+
+        boolean check(int x, int z) {
+            return x >= minX && x <= maxX && z >= minZ && z <= maxZ;
+        }
+    }
+
+    private static class ProxiedPos extends Position2 {
+        public ProxiedPos(Position2 p) {
+            super(p.getX(), p.getZ());
+        }
+
+        @Override
+        public void setX(int x) {
+            throw new IllegalStateException("This Position2 may not be modified");
+        }
+
+        @Override
+        public void setZ(int z) {
+            throw new IllegalStateException("This Position2 may not be modified");
+        }
     }
 }

core/src/main/java/com/volmit/iris/core/safeguard/IrisSafeguard.java

@@ -1,6 +1,7 @@
 package com.volmit.iris.core.safeguard;
 
 import com.volmit.iris.Iris;
+import com.volmit.iris.core.IrisSettings;
 
 public class IrisSafeguard {
     public static boolean unstablemode = false;
@@ -11,5 +12,13 @@ public class IrisSafeguard {
         Iris.info("Enabled Iris SafeGuard");
         ServerBootSFG.BootCheck();
     }
+
+    public static void earlySplash() {
+        if (ServerBootSFG.safeguardPassed || IrisSettings.get().getGeneral().DoomsdayAnnihilationSelfDestructMode)
+            return;
+
+        Iris.instance.splash();
+        UtilsSFG.splash();
+    }
 }
 

core/src/main/java/com/volmit/iris/core/safeguard/ServerBootSFG.java

@@ -3,6 +3,7 @@ package com.volmit.iris.core.safeguard;
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.nms.INMS;
 import com.volmit.iris.core.nms.v1X.NMSBinding1X;
+import com.volmit.iris.engine.object.IrisContextInjector;
 import org.bukkit.Bukkit;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.PluginManager;
@@ -29,6 +30,7 @@ public class ServerBootSFG {
     public static boolean isJRE = false;
     public static boolean hasPrivileges = true;
     public static boolean unsuportedversion = false;
+    public static boolean missingDimensionTypes = false;
     protected static boolean safeguardPassed;
     public static boolean passedserversoftware = true;
     protected static int count;
@@ -110,6 +112,12 @@ public class ServerBootSFG {
             severityMedium++;
         }
 
+        if (IrisContextInjector.isMissingDimensionTypes()) {
+            missingDimensionTypes = true;
+            joiner.add("Missing Dimension Types");
+            severityHigh++;
+        }
+
         allIncompatibilities = joiner.toString();
 
         safeguardPassed = (severityHigh == 0 && severityMedium == 0 && severityLow == 0);

core/src/main/java/com/volmit/iris/core/safeguard/UtilsSFG.java

@@ -39,6 +39,11 @@ public class UtilsSFG {
                 Iris.safeguard(C.RED + "Server Version");
                 Iris.safeguard(C.RED + "- Iris only supports 1.20.1 > 1.21.4");
             }
+            if (ServerBootSFG.missingDimensionTypes) {
+                Iris.safeguard(C.RED + "Dimension Types");
+                Iris.safeguard(C.RED + "- Required Iris dimension types were not loaded.");
+                Iris.safeguard(C.RED + "- If this still happens after a restart please contact support.");
+            }
             if (!ServerBootSFG.passedserversoftware) {
                 Iris.safeguard(C.YELLOW + "Unsupported Server Software");
                 Iris.safeguard(C.YELLOW + "- Please consider using Paper or Purpur instead.");

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

@@ -146,8 +146,8 @@ public class IrisPackBenchmarking {
         IrisToolbelt.pregenerate(PregenTask
                 .builder()
                 .gui(gui)
-                .width(radius)
-                .height(radius)
+                .radiusX(radius)
+                .radiusZ(radius)
                 .build(), Bukkit.getWorld("benchmark")
         );
     }

core/src/main/java/com/volmit/iris/engine/object/IrisContextInjector.java

@@ -2,11 +2,15 @@ package com.volmit.iris.engine.object;
 
 import com.volmit.iris.core.nms.INMS;
 import com.volmit.iris.core.nms.container.AutoClosing;
+import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.misc.ServerProperties;
+import lombok.Getter;
 import org.bukkit.Bukkit;
+import org.bukkit.NamespacedKey;
 import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
 import org.bukkit.event.world.WorldInitEvent;
 
@@ -15,15 +19,12 @@ import java.util.List;
 import static com.volmit.iris.Iris.instance;
 
 public class IrisContextInjector implements Listener {
+    @Getter
+    private static boolean missingDimensionTypes = false;
     private AutoClosing autoClosing = null;
-    private final int totalWorlds;
-    private int worldCounter = 0;
 
     public IrisContextInjector() {
-        if (!Bukkit.getWorlds().isEmpty()) {
-            totalWorlds = 0;
-            return;
-        }
+        if (!Bukkit.getWorlds().isEmpty()) return;
 
         String levelName = ServerProperties.LEVEL_NAME;
         List<String> irisWorlds = irisWorlds();
@@ -31,22 +32,20 @@ public class IrisContextInjector implements Listener {
         boolean nether = irisWorlds.contains(levelName + "_nether");
         boolean end = irisWorlds.contains(levelName + "_end");
 
-        int i = 1;
-        if (Bukkit.getAllowNether()) i++;
-        if (Bukkit.getAllowEnd()) i++;
-
-        if (overworld || nether || end) {
-            var pair = INMS.get().injectUncached(overworld, nether, end);
-            i += pair.getA() - 3;
-            autoClosing = pair.getB();
+        if (INMS.get().missingDimensionTypes(overworld, nether, end)) {
+            missingDimensionTypes = true;
+            return;
         }
 
-        totalWorlds = i;
+        if (overworld || nether || end) {
+            autoClosing = INMS.get().injectUncached(overworld, nether, end);
+        }
+
+        instance.registerListener(this);
     }
 
-    @EventHandler
+    @EventHandler(priority = EventPriority.LOWEST)
     public void on(WorldInitEvent event) {
-        if (++worldCounter < totalWorlds) return;
         if (autoClosing != null) {
             autoClosing.close();
             autoClosing = null;

core/src/main/java/com/volmit/iris/engine/platform/BukkitChunkGenerator.java

@@ -21,6 +21,7 @@ package com.volmit.iris.engine.platform;
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.loader.IrisData;
 import com.volmit.iris.core.nms.INMS;
+import com.volmit.iris.core.nms.container.AutoClosing;
 import com.volmit.iris.core.service.StudioSVC;
 import com.volmit.iris.engine.IrisEngine;
 import com.volmit.iris.engine.data.chunk.TerrainChunk;
@@ -48,6 +49,7 @@ import org.bukkit.block.data.BlockData;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
 import org.bukkit.event.world.WorldInitEvent;
 import org.bukkit.generator.BiomeProvider;
@@ -122,11 +124,13 @@ public class BukkitChunkGenerator extends ChunkGenerator implements PlatformChun
         }
     }
 
-    @EventHandler
+    @EventHandler(priority = EventPriority.LOWEST)
     public void onWorldInit(WorldInitEvent event) {
         try {
             if (initialized || !world.name().equals(event.getWorld().getName()))
                 return;
+            AutoClosing.closeContext();
+            INMS.get().removeCustomDimensions(event.getWorld());
             world.setRawWorldSeed(event.getWorld().getSeed());
             Engine engine = getEngine(event.getWorld());
             if (engine == null) {

core/src/main/java/com/volmit/iris/util/collection/KList.java

@@ -26,6 +26,8 @@ import com.volmit.iris.util.math.RNG;
 import java.util.*;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import java.util.stream.Collector;
+import java.util.stream.Collectors;
 
 @SuppressWarnings("ALL")
 public class KList<T> extends ArrayList<T> implements List<T> {
@@ -65,6 +67,10 @@ public class KList<T> extends ArrayList<T> implements List<T> {
         return s;
     }
 
+    public static <T> Collector<T, ?, KList<T>> collector() {
+        return Collectors.toCollection(KList::new);
+    }
+
     public static KList<String> asStringList(List<?> oo) {
         KList<String> s = new KList<String>();
 

core/src/main/java/com/volmit/iris/util/math/Spiraler.java

@@ -63,7 +63,7 @@ public class Spiraler {
 
     public void next() {
         if ((-sizeX / 2 <= x) && (x <= sizeX / 2) && (-sizeZ / 2 <= z) && (z <= sizeZ / 2)) {
-            spiraled.on(x + ox, z + ox);
+            spiraled.on(x + ox, z + oz);
         }
 
         if ((x == z) || ((x < 0) && (x == -z)) || ((x > 0) && (x == 1 - z))) {

core/src/main/java/com/volmit/iris/util/misc/ServerProperties.java

@@ -10,7 +10,7 @@ public class ServerProperties {
     public static final File SERVER_PROPERTIES;
     public static final File BUKKIT_YML;
 
-    public static final String LEVEL_NAME = DATA.getProperty("level-name", "world");
+    public static final String LEVEL_NAME;
 
     static {
         String[] args = ProcessHandle.current()
@@ -20,11 +20,13 @@ public class ServerProperties {
 
         String propertiesPath = "server.properties";
         String bukkitYml = "bukkit.yml";
+        String levelName = null;
 
         for (int i = 0; i < args.length - 1; i++) {
             switch (args[i]) {
                 case "-c", "--config" -> propertiesPath = args[i + 1];
                 case "-b", "--bukkit-settings" -> bukkitYml = args[i + 1];
+                case "-w", "--level-name", "--world" -> levelName = args[i + 1];
             }
         }
 
@@ -35,5 +37,8 @@ public class ServerProperties {
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
+
+        if (levelName != null) LEVEL_NAME = levelName;
+        else LEVEL_NAME = DATA.getProperty("level-name", "world");
     }
 }

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

@@ -38,7 +38,9 @@ import net.minecraft.tags.TagKey;
 import net.minecraft.world.entity.EntityDimensions;
 import net.minecraft.world.level.LevelReader;
 import net.minecraft.world.level.biome.BiomeSource;
+import net.minecraft.world.level.biome.Biomes;
 import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
@@ -47,6 +49,9 @@ 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.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -640,50 +645,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public com.volmit.iris.core.nms.container.Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().registryOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new com.volmit.iris.core.nms.container.Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -692,7 +655,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -700,26 +668,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.registryOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().registryOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().K.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.registryOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.registryOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.registry(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.registryOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.getHolderOrThrow(ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()))),
-                levelStems.getOrThrow(key).generator()
+                dimensions.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, loc)).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), Lifecycle.stable());
     }
 
@@ -732,4 +740,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return new ResourceLocation("iris", key.location().getPath());
+    }
 }

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

@@ -28,9 +28,14 @@ import net.minecraft.server.WorldLoader;
 import net.minecraft.server.commands.data.BlockDataAccessor;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -641,50 +646,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public com.volmit.iris.core.nms.container.Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().registryOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new com.volmit.iris.core.nms.container.Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -693,7 +656,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -701,26 +669,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.registryOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().registryOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().K.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.registryOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.registryOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.registry(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.registryOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.getHolderOrThrow(ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()))),
-                levelStems.getOrThrow(key).generator()
+                dimensions.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, loc)).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), Lifecycle.stable());
     }
 
@@ -733,4 +741,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return new ResourceLocation("iris", key.location().getPath());
+    }
 }

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

@@ -28,9 +28,14 @@ import net.minecraft.server.WorldLoader;
 import net.minecraft.server.commands.data.BlockDataAccessor;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -642,50 +647,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public com.volmit.iris.core.nms.container.Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().registryOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new com.volmit.iris.core.nms.container.Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -694,7 +657,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -702,26 +670,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.registryOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().registryOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().K.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.registryOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.registryOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.registry(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.registryOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.getHolderOrThrow(ResourceKey.create(Registries.DIMENSION_TYPE, new ResourceLocation("iris", key.location().getPath()))),
-                levelStems.getOrThrow(key).generator()
+                dimensions.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, loc)).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), Lifecycle.stable());
     }
 
@@ -734,4 +742,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return new ResourceLocation("iris", key.location().getPath());
+    }
 }

nms/v1_20_R4/src/main/java/com/volmit/iris/core/nms/v1_20_R4/NMSBinding.java

@@ -38,11 +38,16 @@ import net.minecraft.server.level.ServerLevel;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.item.component.CustomData;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.chunk.status.ChunkStatus;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -667,50 +672,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public com.volmit.iris.core.nms.container.Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().registryOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new com.volmit.iris.core.nms.container.Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -719,7 +682,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -727,26 +695,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.registryOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().registryOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().K.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.registryOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.registryOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.registry(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.registryOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.getHolder(new ResourceLocation("iris", key.location().getPath())).orElseThrow(),
-                levelStems.getOrThrow(key).generator()
+                dimensions.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, loc)).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), RegistrationInfo.BUILT_IN);
     }
 
@@ -759,4 +767,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return new ResourceLocation("iris", key.location().getPath());
+    }
 }

nms/v1_21_R1/src/main/java/com/volmit/iris/core/nms/v1_21_R1/NMSBinding.java

@@ -32,11 +32,16 @@ import net.minecraft.server.level.ChunkMap;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.item.component.CustomData;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.chunk.status.ChunkStatus;
 import net.minecraft.world.level.chunk.status.WorldGenContext;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -671,50 +676,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public com.volmit.iris.core.nms.container.Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().registryOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new com.volmit.iris.core.nms.container.Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -723,7 +686,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -731,26 +699,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.registryOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().registryOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().K.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.registryOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.registryOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.registry(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.registryOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.getHolder(ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath())).orElseThrow(),
-                levelStems.getOrThrow(key).generator()
+                dimensions.getHolder(ResourceKey.create(Registries.DIMENSION_TYPE, loc)).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), RegistrationInfo.BUILT_IN);
     }
 
@@ -763,4 +771,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath());
+    }
 }

nms/v1_21_R2/src/main/java/com/volmit/iris/core/nms/v1_21_R2/NMSBinding.java

@@ -27,11 +27,16 @@ import net.minecraft.server.commands.data.BlockDataAccessor;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.item.component.CustomData;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.chunk.status.ChunkStatus;
 import net.minecraft.world.level.chunk.status.WorldGenContext;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -661,50 +666,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                        old.resources(),
-                        old.dataConfiguration(),
-                        old.datapackWorldgen(),
-                        createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().lookupOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -713,7 +676,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -721,26 +689,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.lookupOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().lookupOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().L.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.lookupOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.lookupOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.lookup(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.lookupOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.get(ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath())).orElseThrow(),
-                levelStems.getValueOrThrow(key).generator()
+                dimensions.get(loc).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), RegistrationInfo.BUILT_IN);
     }
 
@@ -753,4 +761,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath());
+    }
 }

nms/v1_21_R3/src/main/java/com/volmit/iris/core/nms/v1_21_R3/NMSBinding.java

@@ -39,7 +39,9 @@ import net.minecraft.tags.TagKey;
 import net.minecraft.world.entity.EntityType;
 import net.minecraft.world.item.component.CustomData;
 import net.minecraft.world.level.LevelReader;
+import net.minecraft.world.level.biome.Biomes;
 import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
@@ -49,6 +51,9 @@ import net.minecraft.world.level.chunk.status.ChunkStatus;
 import net.minecraft.world.level.chunk.status.WorldGenContext;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
+import net.minecraft.world.level.levelgen.FlatLevelSource;
+import net.minecraft.world.level.levelgen.flat.FlatLayerInfo;
+import net.minecraft.world.level.levelgen.flat.FlatLevelGeneratorSettings;
 import org.bukkit.*;
 import org.bukkit.block.Biome;
 import org.bukkit.block.data.BlockData;
@@ -660,50 +665,8 @@ public class NMSBinding implements INMSBinding {
     }
 
     @Override
+    @SneakyThrows
     public AutoClosing injectLevelStems() {
-        return inject(this::supplier);
-    }
-
-    @Override
-    @SneakyThrows
-    public Pair<Integer, AutoClosing> injectUncached(boolean overworld, boolean nether, boolean end) {
-        var reg = registry();
-        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
-        field.setAccessible(true);
-
-        AutoClosing closing = inject(old -> new WorldLoader.DataLoadContext(
-                    old.resources(),
-                    old.dataConfiguration(),
-                    old.datapackWorldgen(),
-                    createRegistryAccess(old.datapackDimensions(), true, overworld, nether, end)
-                )
-        );
-
-        var injected = ((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions().lookupOrThrow(Registries.LEVEL_STEM);
-        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
-        var fake = new HashMap<>(old);
-        fake.put(Registries.LEVEL_STEM, injected);
-        field.set(reg, fake);
-
-        return new Pair<>(
-                injected.size(),
-                new AutoClosing(() -> {
-                    closing.close();
-                    field.set(reg, old);
-                }));
-    }
-
-    private WorldLoader.DataLoadContext supplier(WorldLoader.DataLoadContext old) {
-        return dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
-                old.resources(),
-                old.dataConfiguration(),
-                old.datapackWorldgen(),
-                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
-        ));
-    }
-
-    @SneakyThrows
-    private AutoClosing inject(Function<WorldLoader.DataLoadContext, WorldLoader.DataLoadContext> transformer) {
         if (!dataContextLock.tryLock()) throw new IllegalStateException("Failed to inject data context!");
 
         var server = ((CraftServer) Bukkit.getServer());
@@ -712,7 +675,12 @@ public class NMSBinding implements INMSBinding {
         var old = nmsServer.worldLoader;
 
         field.setAccessible(true);
-        field.set(nmsServer, transformer.apply(old));
+        field.set(nmsServer, dataLoadContext.aquire(() -> new WorldLoader.DataLoadContext(
+                old.resources(),
+                old.dataConfiguration(),
+                old.datapackWorldgen(),
+                createRegistryAccess(old.datapackDimensions(), false, true, true, true)
+        )));
 
         return new AutoClosing(() -> {
             field.set(nmsServer, old);
@@ -720,26 +688,66 @@ public class NMSBinding implements INMSBinding {
         });
     }
 
+    @Override
+    @SneakyThrows
+    public AutoClosing injectUncached(boolean overworld, boolean nether, boolean end) {
+        var reg = registry();
+        var field = getField(RegistryAccess.ImmutableRegistryAccess.class, Map.class);
+        field.setAccessible(true);
+
+        var access = createRegistryAccess(((CraftServer) Bukkit.getServer()).getServer().worldLoader.datapackDimensions(), true, overworld, nether, end);
+        var injected = access.lookupOrThrow(Registries.LEVEL_STEM);
+        var old = (Map<ResourceKey<? extends Registry<?>>, Registry<?>>) field.get(reg);
+        var fake = new HashMap<>(old);
+        fake.put(Registries.LEVEL_STEM, injected);
+        field.set(reg, fake);
+
+        return new AutoClosing(() -> field.set(reg, old));
+    }
+
+    @Override
+    public boolean missingDimensionTypes(boolean overworld, boolean nether, boolean end) {
+        var registry = registry().lookupOrThrow(Registries.DIMENSION_TYPE);
+        if (overworld) overworld = !registry.containsKey(createIrisKey(LevelStem.OVERWORLD));
+        if (nether) nether = !registry.containsKey(createIrisKey(LevelStem.NETHER));
+        if (end) end = !registry.containsKey(createIrisKey(LevelStem.END));
+        return overworld || nether || end;
+    }
+
+    @Override
+    public void removeCustomDimensions(World world) {
+        ((CraftWorld) world).getHandle().L.customDimensions = null;
+    }
+
     private RegistryAccess.Frozen createRegistryAccess(RegistryAccess.Frozen datapack, boolean copy, boolean overworld, boolean nether, boolean end) {
         var access = registry();
         var dimensions = access.lookupOrThrow(Registries.DIMENSION_TYPE);
-        var levelStems = access.lookupOrThrow(Registries.LEVEL_STEM);
 
+        var settings = new FlatLevelGeneratorSettings(
+                Optional.empty(),
+                access.lookupOrThrow(Registries.BIOME).getOrThrow(Biomes.THE_VOID),
+                List.of()
+        );
+        settings.getLayersInfo().add(new FlatLayerInfo(1, Blocks.AIR));
+        settings.updateLayers();
+
+        var source = new FlatLevelSource(settings);
         var fake = new MappedRegistry<>(Registries.LEVEL_STEM, Lifecycle.experimental());
-        if (overworld) register(fake, levelStems, dimensions, LevelStem.OVERWORLD);
-        if (nether) register(fake, levelStems, dimensions, LevelStem.NETHER);
-        if (end) register(fake, levelStems, dimensions, LevelStem.END);
+        if (overworld) register(fake, dimensions, source, LevelStem.OVERWORLD);
+        if (nether) register(fake, dimensions, source, LevelStem.NETHER);
+        if (end) register(fake, dimensions, source, LevelStem.END);
         copy(fake, datapack.lookup(Registries.LEVEL_STEM).orElse(null));
 
-        if (copy) copy(fake, levelStems);
+        if (copy) copy(fake, access.lookupOrThrow(Registries.LEVEL_STEM));
 
-        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake.freeze())).freeze();
+        return new RegistryAccess.Frozen.ImmutableRegistryAccess(List.of(fake)).freeze();
     }
 
-    private void register(MappedRegistry<LevelStem> target, Registry<LevelStem> levelStems, Registry<DimensionType> dimensions, ResourceKey<LevelStem> key) {
+    private void register(MappedRegistry<LevelStem> target, Registry<DimensionType> dimensions, FlatLevelSource source, ResourceKey<LevelStem> key) {
+        var loc = createIrisKey(key);
         target.register(key, new LevelStem(
-                dimensions.get(ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath())).orElseThrow(),
-                levelStems.getValueOrThrow(key).generator()
+                dimensions.get(loc).orElseThrow(() -> new IllegalStateException("Missing dimension type " + loc + " in " + dimensions.keySet())),
+                source
         ), RegistrationInfo.BUILT_IN);
     }
 
@@ -752,4 +760,8 @@ public class NMSBinding implements INMSBinding {
                 target.register(key, value, info);
         });
     }
+
+    private ResourceLocation createIrisKey(ResourceKey<LevelStem> key) {
+        return ResourceLocation.fromNamespaceAndPath("iris", key.location().getPath());
+    }
 }