Allow placing datapack structures in Iris worlds (#1225)

* Allow placing datapack structures in Iris worlds

* command for generating configs for datapack structures

* remove the sub dir from the snippet key

core/build.gradle.kts

@@ -83,6 +83,7 @@ dependencies {
     slim(libs.commons.io)
     slim(libs.commons.lang)
     slim(libs.commons.lang3)
+    slim(libs.commons.math3)
     slim(libs.oshi)
     slim(libs.lz4)
     slim(libs.fastutil)

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

@@ -18,19 +18,29 @@
 
 package com.volmit.iris.core.commands;
 
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.volmit.iris.Iris;
 import com.volmit.iris.core.ServerConfigurator;
+import com.volmit.iris.core.loader.IrisData;
+import com.volmit.iris.core.nms.INMS;
 import com.volmit.iris.core.nms.datapack.DataVersion;
 import com.volmit.iris.core.service.IrisEngineSVC;
 import com.volmit.iris.core.tools.IrisPackBenchmarking;
 import com.volmit.iris.core.tools.IrisToolbelt;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.engine.object.IrisDimension;
+import com.volmit.iris.engine.object.annotations.Snippet;
+import com.volmit.iris.util.collection.KSet;
 import com.volmit.iris.util.context.IrisContext;
+import com.volmit.iris.engine.object.IrisJigsawStructurePlacement;
+import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.decree.DecreeExecutor;
 import com.volmit.iris.util.decree.DecreeOrigin;
 import com.volmit.iris.util.decree.annotations.Decree;
 import com.volmit.iris.util.decree.annotations.Param;
+import com.volmit.iris.util.decree.specialhandlers.NullableDimensionHandler;
 import com.volmit.iris.util.format.C;
 import com.volmit.iris.util.format.Form;
 import com.volmit.iris.util.io.CountingDataInputStream;
@@ -42,6 +52,7 @@ import com.volmit.iris.util.nbt.mca.MCAFile;
 import com.volmit.iris.util.nbt.mca.MCAUtil;
 import com.volmit.iris.util.parallel.MultiBurst;
 import com.volmit.iris.util.plugin.VolmitSender;
+import lombok.SneakyThrows;
 import net.jpountz.lz4.LZ4BlockInputStream;
 import net.jpountz.lz4.LZ4BlockOutputStream;
 import net.jpountz.lz4.LZ4FrameInputStream;
@@ -59,6 +70,8 @@ import java.util.*;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import java.util.zip.GZIPInputStream;
 import java.util.zip.GZIPOutputStream;
 
@@ -143,6 +156,130 @@ public class CommandDeveloper implements DecreeExecutor {
         }
     }
 
+    @SneakyThrows
+    @Decree(description = "Generate Iris structures for all loaded datapack structures")
+    public void generateStructures(
+            @Param(description = "The pack to add the generated structures to", aliases = "pack", defaultValue = "---", customHandler = NullableDimensionHandler.class)
+            IrisDimension dimension,
+            @Param(description = "Ignore existing structures", defaultValue = "false")
+            boolean force
+    ) {
+        var map = INMS.get().collectStructures();
+        if (map.isEmpty()) {
+            sender().sendMessage(C.IRIS + "No structures found");
+            return;
+        }
+
+        sender().sendMessage(C.IRIS + "Found " + map.size() + " structures");
+
+        final File dataDir;
+        final IrisData data;
+        final Set<String> existingStructures;
+        final Map<String, Set<String>> snippets;
+        final File dimensionFile;
+        final File structuresFolder;
+        final File snippetsFolder;
+
+        var dimensionObj = new JsonObject();
+
+        if (dimension == null) {
+            dataDir = Iris.instance.getDataFolder("structures");
+            IO.delete(dataDir);
+            data = IrisData.get(dataDir);
+            existingStructures = Set.of();
+            snippets = Map.of();
+            dimensionFile = new File(dataDir, "structures.json");
+        } else {
+            data = dimension.getLoader();
+            dataDir = data.getDataFolder();
+            existingStructures = new KSet<>(data.getJigsawStructureLoader().getPossibleKeys());
+
+            dimensionObj = data.getGson().fromJson(IO.readAll(dimension.getLoadFile()), JsonObject.class);
+            snippets = Optional.ofNullable(dimensionObj.getAsJsonArray("jigsawStructures"))
+                    .map(array -> array.asList()
+                            .stream()
+                            .filter(JsonElement::isJsonPrimitive)
+                            .collect(Collectors.toMap(element -> data.getGson()
+                                            .fromJson(element, IrisJigsawStructurePlacement.class)
+                                            .getStructure(),
+                                    element -> Set.of(element.getAsString()),
+                                    KSet::merge)))
+                    .orElse(Map.of());
+
+            dimensionFile = dimension.getLoadFile();
+        }
+        structuresFolder = new File(dataDir, "jigsaw-structures");
+        snippetsFolder = new File(dataDir, "snippet" + "/" + IrisJigsawStructurePlacement.class.getAnnotation(Snippet.class).value());
+
+        var gson = data.getGson();
+        var jigsawStructures = Optional.ofNullable(dimensionObj.getAsJsonArray("jigsawStructures"))
+                .orElse(new JsonArray(map.size()));
+
+        map.forEach((key, placement) -> {
+            String loadKey = "datapack/" + key.namespace() + "/" + key.key();
+            if (existingStructures.contains(loadKey) && !force)
+                return;
+
+            var structures = placement.structures();
+            var obj = placement.toJson(loadKey);
+            if (obj == null || structures.isEmpty()) {
+                sender().sendMessage(C.RED + "Failed to generate hook for " + key);
+                return;
+            }
+            File snippetFile = new File(snippetsFolder, loadKey + ".json");
+            try {
+                IO.writeAll(snippetFile, gson.toJson(obj));
+            } catch (IOException e) {
+                sender().sendMessage(C.RED + "Failed to generate snippet for " + key);
+                e.printStackTrace();
+                return;
+            }
+
+            Set<String> loadKeys = snippets.getOrDefault(loadKey, Set.of(loadKey));
+            jigsawStructures.asList().removeIf(e -> loadKeys.contains((e.isJsonObject() ? e.getAsJsonObject().get("structure") : e).getAsString()));
+            jigsawStructures.add("snippet/" + loadKey);
+
+            String structureKey;
+            if (structures.size() > 1) {
+                KList<String> common = new KList<>();
+                for (int i = 0; i < structures.size(); i++) {
+                    var tags = structures.get(i).tags();
+                    if (i == 0) common.addAll(tags);
+                    else common.removeIf(tag -> !tags.contains(tag));
+                }
+                structureKey = common.isNotEmpty() ? "#" + common.getFirst() : structures.getFirst().key();
+            } else structureKey = structures.getFirst().key();
+
+            JsonArray array = new JsonArray();
+            if (structures.size() > 1) {
+                structures.stream()
+                        .flatMap(structure -> {
+                            String[] arr = new String[structure.weight()];
+                            Arrays.fill(arr, structure.key());
+                            return Arrays.stream(arr);
+                        })
+                        .forEach(array::add);
+            } else array.add(structureKey);
+
+            obj = new JsonObject();
+            obj.addProperty("structureKey", structureKey);
+            obj.add("datapackStructures", array);
+
+            File out = new File(structuresFolder, loadKey + ".json");
+            out.getParentFile().mkdirs();
+            try {
+                IO.writeAll(out, gson.toJson(obj));
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        });
+
+        dimensionObj.add("jigsawStructures", jigsawStructures);
+        IO.writeAll(dimensionFile, gson.toJson(dimensionObj));
+
+        data.hotloaded();
+    }
+
     @Decree(description = "Test")
     public void packBenchmark(
             @Param(description = "The pack to bench", aliases = {"pack"}, defaultValue = "overworld")

core/src/main/java/com/volmit/iris/core/loader/IrisData.java

@@ -425,6 +425,7 @@ public class IrisData implements ExclusionStrategy, TypeAdapterFactory {
         }
 
         String snippetType = typeToken.getRawType().getDeclaredAnnotation(Snippet.class).value();
+        String snippedBase = "snippet/" + snippetType + "/";
 
         return new TypeAdapter<>() {
             @Override
@@ -438,19 +439,20 @@ public class IrisData implements ExclusionStrategy, TypeAdapterFactory {
 
                 if (reader.peek().equals(JsonToken.STRING)) {
                     String r = reader.nextString();
+                    if (!r.startsWith("snippet/"))
+                        return null;
+                    if (!r.startsWith(snippedBase))
+                        r = snippedBase + r.substring(8);
 
-                    if (r.startsWith("snippet/" + snippetType + "/")) {
-                        File f = new File(getDataFolder(), r + ".json");
-
-                        if (f.exists()) {
-                            try (JsonReader snippetReader = new JsonReader(new FileReader(f))){
-                                return adapter.read(snippetReader);
-                            } catch (Throwable e) {
-                                Iris.error("Couldn't read snippet " + r + " in " + reader.getPath() + " (" + e.getMessage() + ")");
-                            }
-                        } else {
-                            Iris.error("Couldn't find snippet " + r + " in " + reader.getPath());
+                    File f = new File(getDataFolder(), r + ".json");
+                    if (f.exists()) {
+                        try (JsonReader snippetReader = new JsonReader(new FileReader(f))){
+                            return adapter.read(snippetReader);
+                        } catch (Throwable e) {
+                            Iris.error("Couldn't read snippet " + r + " in " + reader.getPath() + " (" + e.getMessage() + ")");
                         }
+                    } else {
+                        Iris.error("Couldn't find snippet " + r + " in " + reader.getPath());
                     }
 
                     return null;
@@ -488,7 +490,7 @@ public class IrisData implements ExclusionStrategy, TypeAdapterFactory {
                         .map(s -> s.substring(absPath.length() + 1))
                         .map(s -> s.replace("\\", "/"))
                         .map(s -> s.split("\\Q.\\E")[0])
-                        .forEach(s -> l.add("snippet/" + f + "/" + s));
+                        .forEach(s -> l.add("snippet/" + s));
             } catch (Throwable e) {
                 e.printStackTrace();
             }

core/src/main/java/com/volmit/iris/core/loader/IrisRegistrant.java

@@ -28,6 +28,7 @@ import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.json.JSONObject;
 import com.volmit.iris.util.plugin.VolmitSender;
 import lombok.Data;
+import lombok.EqualsAndHashCode;
 
 import java.awt.*;
 import java.io.File;
@@ -39,6 +40,7 @@ public abstract class IrisRegistrant {
     @ArrayType(min = 1, type = String.class)
     private KList<String> preprocessors = new KList<>();
 
+    @EqualsAndHashCode.Exclude
     private transient IrisData loader;
 
     private transient String loadKey;

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

@@ -18,8 +18,12 @@
 
 package com.volmit.iris.core.nms;
 
+import com.volmit.iris.core.link.Identifier;
+import com.volmit.iris.core.nms.container.AutoClosing;
 import com.volmit.iris.core.nms.container.BiomeColor;
 import com.volmit.iris.core.nms.container.BlockProperty;
+import com.volmit.iris.core.nms.container.Pair;
+import com.volmit.iris.core.nms.container.StructurePlacement;
 import com.volmit.iris.core.nms.datapack.DataVersion;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.engine.platform.PlatformChunkGenerator;
@@ -136,4 +140,8 @@ public interface INMSBinding {
     }
 
     KMap<Material, List<BlockProperty>> getBlockProperties();
+
+    void placeStructures(Chunk chunk);
+
+    KMap<Identifier, StructurePlacement> collectStructures();
 }

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

@@ -0,0 +1,77 @@
+package com.volmit.iris.core.nms.container;
+
+import com.google.gson.JsonObject;
+import com.volmit.iris.engine.object.IrisJigsawStructurePlacement.SpreadType;
+import lombok.*;
+import lombok.experimental.Accessors;
+import lombok.experimental.SuperBuilder;
+import org.apache.commons.math3.fraction.Fraction;
+
+import java.util.List;
+
+@Data
+@SuperBuilder
+@Accessors(fluent = true, chain = true)
+public abstract class StructurePlacement {
+    private final int salt;
+    private final float frequency;
+    private final List<Structure> structures;
+
+    public abstract JsonObject toJson(String structure);
+
+    protected JsonObject createBase(String structure) {
+        JsonObject object = new JsonObject();
+        object.addProperty("structure", structure);
+        object.addProperty("salt", salt);
+        return object;
+    }
+
+    public int frequencyToSpacing() {
+        var frac = new Fraction(Math.max(Math.min(frequency, 1), 0.000000001f));
+        return (int) Math.round(Math.sqrt((double) frac.getDenominator() / frac.getNumerator()));
+    }
+
+    @Getter
+    @Accessors(chain = true, fluent = true)
+    @EqualsAndHashCode(callSuper = true)
+    @SuperBuilder
+    public static class RandomSpread extends StructurePlacement {
+        private final int spacing;
+        private final int separation;
+        private final SpreadType spreadType;
+
+        @Override
+        public JsonObject toJson(String structure) {
+            JsonObject object = createBase(structure);
+            object.addProperty("spacing", Math.max(spacing, frequencyToSpacing()));
+            object.addProperty("separation", separation);
+            object.addProperty("spreadType", spreadType.name());
+            return object;
+        }
+    }
+
+    @Getter
+    @EqualsAndHashCode(callSuper = true)
+    @SuperBuilder
+    public static class ConcentricRings extends StructurePlacement {
+        private final int distance;
+        private final int spread;
+        private final int count;
+
+        @Override
+        public JsonObject toJson(String structure) {
+            return null;
+        }
+    }
+
+    public record Structure(
+            int weight,
+            String key,
+            List<String> tags
+    ) {
+
+        public boolean isValid() {
+            return weight > 0 && key != null;
+        }
+    }
+}

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

@@ -19,10 +19,13 @@
 package com.volmit.iris.core.nms.v1X;
 
 import com.volmit.iris.Iris;
+import com.volmit.iris.core.link.Identifier;
 import com.volmit.iris.core.nms.INMSBinding;
 import com.volmit.iris.core.nms.container.BiomeColor;
 import com.volmit.iris.core.nms.container.BlockProperty;
 import com.volmit.iris.core.nms.datapack.DataVersion;
+import com.volmit.iris.core.nms.container.Pair;
+import com.volmit.iris.core.nms.container.StructurePlacement;
 import com.volmit.iris.engine.framework.Engine;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.collection.KMap;
@@ -135,6 +138,16 @@ public class NMSBinding1X implements INMSBinding {
         return map;
     }
 
+    @Override
+    public void placeStructures(Chunk chunk) {
+
+    }
+
+    @Override
+    public KMap<Identifier, StructurePlacement> collectStructures() {
+        return new KMap<>();
+    }
+
     @Override
     public CompoundTag serializeEntity(Entity location) {
         return null;

core/src/main/java/com/volmit/iris/engine/mantle/components/MantleJigsawComponent.java

@@ -167,6 +167,7 @@ public class MantleJigsawComponent extends IrisMantleComponent {
 
     @BlockCoordinates
     private boolean place(MantleWriter writer, IrisPosition position, IrisJigsawStructure structure, RNG rng, boolean forcePlace) {
+        if (structure == null || structure.getDatapackStructures().isNotEmpty()) return false;
         return new PlannedStructure(structure, position, rng, forcePlace).place(writer, getMantle(), writer.getEngine());
     }
 

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

@@ -1,43 +0,0 @@
-/*
- * Iris is a World Generator for Minecraft Bukkit Servers
- * Copyright (c) 2022 Arcane Arts (Volmit Software)
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-
-package com.volmit.iris.engine.object;
-
-import com.volmit.iris.engine.object.annotations.*;
-import lombok.AllArgsConstructor;
-import lombok.Data;
-import lombok.NoArgsConstructor;
-import lombok.experimental.Accessors;
-
-@Snippet("jigsaw-placer")
-@Accessors(chain = true)
-@NoArgsConstructor
-@AllArgsConstructor
-@Desc("Represents a jigsaw placement")
-@Data
-public class IrisJigsawPlacement {
-    @RegistryListResource(IrisJigsawStructure.class)
-    @Required
-    @Desc("The jigsaw structure to use")
-    private String structure = "";
-
-    @Required
-    @MinNumber(1)
-    @Desc("The rarity for this jigsaw structure to place on a per chunk basis")
-    private int rarity = 29;
-}

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

@@ -23,6 +23,7 @@ import com.volmit.iris.core.loader.IrisRegistrant;
 import com.volmit.iris.engine.data.cache.AtomicCache;
 import com.volmit.iris.engine.object.annotations.*;
 import com.volmit.iris.engine.object.annotations.functions.StructureKeyFunction;
+import com.volmit.iris.engine.object.annotations.functions.StructureKeyOrTagFunction;
 import com.volmit.iris.util.collection.KList;
 import com.volmit.iris.util.json.JSONObject;
 import com.volmit.iris.util.plugin.VolmitSender;
@@ -40,6 +41,11 @@ import lombok.experimental.Accessors;
 @Data
 @EqualsAndHashCode(callSuper = false)
 public class IrisJigsawStructure extends IrisRegistrant {
+    @RegistryListFunction(StructureKeyFunction.class)
+    @ArrayType(min = 1, type = String.class)
+    @Desc("The datapack structures. Randomply chooses a structure to place\nIgnores every other setting")
+    private KList<String> datapackStructures = new KList<>();
+
     @RegistryListResource(IrisJigsawPiece.class)
     @Required
     @ArrayType(min = 1, type = String.class)
@@ -70,7 +76,7 @@ public class IrisJigsawStructure extends IrisRegistrant {
     @Desc("Set to true to prevent rotating the initial structure piece")
     private boolean disableInitialRotation = false;
 
-    @RegistryListFunction(StructureKeyFunction.class)
+    @RegistryListFunction(StructureKeyOrTagFunction.class)
     @Desc("The minecraft key to use when creating treasure maps")
     private String structureKey = null;
 
@@ -117,6 +123,10 @@ public class IrisJigsawStructure extends IrisRegistrant {
 
     public int getMaxDimension() {
         return maxDimension.aquire(() -> {
+            if (datapackStructures.isNotEmpty()) {
+                return 0;
+            }
+
             if (useMaxPieceSizeForParallaxRadius) {
                 int max = 0;
                 KList<String> pools = new KList<>();

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

@@ -0,0 +1,74 @@
+package com.volmit.iris.engine.object;
+
+import com.volmit.iris.engine.framework.Engine;
+import com.volmit.iris.engine.framework.EngineAssignedComponent;
+import com.volmit.iris.util.collection.KList;
+import com.volmit.iris.util.documentation.ChunkCoordinates;
+import com.volmit.iris.util.math.Position2;
+import com.volmit.iris.util.math.RNG;
+import com.volmit.iris.util.noise.CNG;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+import java.util.function.BiPredicate;
+
+public class IrisStructurePopulator extends EngineAssignedComponent {
+    private final CNG cng;
+    private final long mantle;
+    private final long jigsaw;
+
+    public IrisStructurePopulator(Engine engine) {
+        super(engine, "Datapack Structures");
+        mantle = engine.getSeedManager().getMantle();
+        jigsaw = engine.getSeedManager().getJigsaw();
+        cng = NoiseStyle.STATIC.create(new RNG(jigsaw));
+    }
+
+    @ChunkCoordinates
+    public void populateStructures(int x, int z, BiPredicate<String, Boolean> placer) {
+        int bX = x << 4, bZ = z << 4;
+        var dimension = getDimension();
+        var region = getEngine().getRegion(bX + 8, bZ + 8);
+        var biome = getEngine().getSurfaceBiome(bX + 8, bZ + 8);
+        var loader = getData().getJigsawStructureLoader();
+
+        long seed = cng.fit(Integer.MIN_VALUE, Integer.MAX_VALUE, x, z);
+        if (dimension.getStronghold() != null) {
+            var list = getDimension().getStrongholds(mantle);
+            if (list != null && list.contains(new Position2(bX, bZ))) {
+                place(placer, loader.load(dimension.getStronghold()), new RNG(seed), true);
+                return;
+            }
+        }
+
+        boolean placed = place(placer, biome.getJigsawStructures(), seed, x, z);
+        if (!placed) placed = place(placer, region.getJigsawStructures(), seed, x, z);
+        if (!placed) place(placer, dimension.getJigsawStructures(), seed, x, z);
+    }
+
+    private boolean place(BiPredicate<String, Boolean> placer, KList<IrisJigsawStructurePlacement> placements, long seed, int x, int z) {
+        var placement = pick(placements, seed, x, z);
+        if (placement == null) return false;
+        return place(placer, getData().getJigsawStructureLoader().load(placement.getStructure()), new RNG(seed), false);
+    }
+
+    @Nullable
+    @ChunkCoordinates
+    private IrisJigsawStructurePlacement pick(List<IrisJigsawStructurePlacement> structures, long seed, int x, int z) {
+        return IRare.pick(structures.stream()
+                .filter(p -> p.shouldPlace(getData(), getDimension().getJigsawStructureDivisor(), jigsaw, x, z))
+                .toList(), new RNG(seed).nextDouble());
+    }
+
+    @ChunkCoordinates
+    private boolean place(BiPredicate<String, Boolean> placer, IrisJigsawStructure structure, RNG rng, boolean ignoreBiomes) {
+        if (structure == null || structure.getDatapackStructures().isEmpty()) return false;
+        var keys = structure.getDatapackStructures().shuffleCopy(rng);
+        while (keys.isNotEmpty()) {
+            String key = keys.removeFirst();
+            if (key != null && placer.test(key, ignoreBiomes || structure.isForcePlace()))
+                return true;
+        }
+        return false;
+    }
+}

core/src/main/java/com/volmit/iris/engine/object/annotations/functions/StructureKeyFunction.java

@@ -18,6 +18,6 @@ public class StructureKeyFunction implements ListFunction<KList<String>> {
 
     @Override
     public KList<String> apply(IrisData irisData) {
-        return INMS.get().getStructureKeys();
+        return INMS.get().getStructureKeys().removeWhere(t -> t.startsWith("#"));
     }
 }

core/src/main/java/com/volmit/iris/engine/object/annotations/functions/StructureKeyOrTagFunction.java

@@ -0,0 +1,23 @@
+package com.volmit.iris.engine.object.annotations.functions;
+
+import com.volmit.iris.core.loader.IrisData;
+import com.volmit.iris.core.nms.INMS;
+import com.volmit.iris.engine.framework.ListFunction;
+import com.volmit.iris.util.collection.KList;
+
+public class StructureKeyOrTagFunction implements ListFunction<KList<String>> {
+    @Override
+    public String key() {
+        return "structure-key-or-tag";
+    }
+
+    @Override
+    public String fancyName() {
+        return "Structure Key or Tag";
+    }
+
+    @Override
+    public KList<String> apply(IrisData irisData) {
+        return INMS.get().getStructureKeys();
+    }
+}

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

@@ -240,6 +240,7 @@ public class BukkitChunkGenerator extends ChunkGenerator implements PlatformChun
                     }
                 }, syncExecutor));
             }
+            futures.add(CompletableFuture.runAsync(() -> INMS.get().placeStructures(c), syncExecutor));
 
             CompletableFuture.allOf(futures.toArray(new CompletableFuture[0]))
                     .thenRunAsync(() -> {

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

@@ -22,6 +22,7 @@ import org.jetbrains.annotations.NotNull;
 
 import java.io.Serializable;
 import java.util.AbstractSet;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.concurrent.ConcurrentHashMap;
@@ -30,13 +31,15 @@ public class KSet<T> extends AbstractSet<T> implements Serializable {
     private static final long serialVersionUID = 1L;
     private final ConcurrentHashMap<T, Boolean> map;
 
-    public KSet() {
-        map = new ConcurrentHashMap<>();
+    public KSet(Collection<? extends T> c) {
+        this(c.size());
+        addAll(c);
     }
 
-    public KSet(Collection<? extends T> c) {
-        this();
-        addAll(c);
+    @SafeVarargs
+    public KSet(T... values) {
+        this(values.length);
+        addAll(Arrays.asList(values));
     }
 
     public KSet(int initialCapacity, float loadFactor) {
@@ -47,6 +50,13 @@ public class KSet<T> extends AbstractSet<T> implements Serializable {
         map = new ConcurrentHashMap<>(initialCapacity);
     }
 
+    public static <T> KSet<T> merge(Collection<? extends T> first, Collection<? extends T> second) {
+        var set = new KSet<T>();
+        set.addAll(first);
+        set.addAll(second);
+        return set;
+    }
+
     @Override
     public int size() {
         return map.size();

core/src/main/java/com/volmit/iris/util/decree/specialhandlers/NullableDimensionHandler.java

@@ -0,0 +1,88 @@
+/*
+ * Iris is a World Generator for Minecraft Bukkit Servers
+ * Copyright (c) 2022 Arcane Arts (Volmit Software)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.volmit.iris.util.decree.specialhandlers;
+
+import com.volmit.iris.Iris;
+import com.volmit.iris.core.IrisSettings;
+import com.volmit.iris.core.loader.IrisData;
+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.decree.DecreeParameterHandler;
+import com.volmit.iris.util.decree.exceptions.DecreeParsingException;
+
+import java.io.File;
+
+public class NullableDimensionHandler implements DecreeParameterHandler<IrisDimension> {
+    @Override
+    public KList<IrisDimension> getPossibilities() {
+        KMap<String, IrisDimension> p = new KMap<>();
+
+        //noinspection ConstantConditions
+        for (File i : Iris.instance.getDataFolder("packs").listFiles()) {
+            if (i.isDirectory()) {
+                IrisData data = IrisData.get(i);
+                for (IrisDimension j : data.getDimensionLoader().loadAll(data.getDimensionLoader().getPossibleKeys())) {
+                    p.putIfAbsent(j.getLoadKey(), j);
+                }
+
+                data.close();
+            }
+        }
+
+        return p.v();
+    }
+
+    @Override
+    public String toString(IrisDimension dim) {
+        return dim.getLoadKey();
+    }
+
+    @Override
+    public IrisDimension parse(String in, boolean force) throws DecreeParsingException {
+        if (in.equalsIgnoreCase("---"))
+            return null;
+
+        if (in.equalsIgnoreCase("default")) {
+            return parse(IrisSettings.get().getGenerator().getDefaultWorldType());
+        }
+
+        KList<IrisDimension> options = getPossibilities(in);
+
+
+        if (options.isEmpty()) {
+            throw new DecreeParsingException("Unable to find Dimension \"" + in + "\"");
+        }
+        try {
+            return options.stream().filter((i) -> toString(i).equalsIgnoreCase(in)).toList().get(0);
+        } catch (Throwable e) {
+            throw new DecreeParsingException("Unable to filter which Dimension \"" + in + "\"");
+        }
+    }
+
+    @Override
+    public boolean supports(Class<?> type) {
+        return type.equals(IrisDimension.class);
+    }
+
+    @Override
+    public String getRandomDefault() {
+        return "dimension";
+    }
+}