[Changes] Make sure BCLBiomes do not keep cyclic/order dependant references

src/main/java/org/betterx/bclib/api/v2/generator/BCLibEndBiomeSource.java

@@ -145,7 +145,7 @@ public class BCLibEndBiomeSource extends BCLBiomeSource implements BiomeSourceWi
             }
 
 
-            if (bclBiome != null || bclBiome != BCLBiomeRegistry.EMPTY_BIOME) {
+            if (!BCLBiomeRegistry.isEmptyBiome(bclBiome)) {
                 if (bclBiome.getParentBiome() == null) {
                     //ignore small islands when void biomes are disabled
                     if (!config.withVoidBiomes) {
@@ -165,7 +165,7 @@ public class BCLibEndBiomeSource extends BCLBiomeSource implements BiomeSourceWi
                     }
 
                     if (!didForceAdd) {
-                        if (biomeID.equals(BCLBiomeRegistry.EMPTY_BIOME.getID())
+                        if (BCLBiomeRegistry.isEmptyBiome(biomeID)
                                 || bclBiome.getIntendedType().is(BiomeAPI.BiomeType.END_IGNORE)) {
                             //we should not add this biome anywhere, so just ignore it
                         } else {

src/main/java/org/betterx/bclib/api/v2/generator/BCLibNetherBiomeSource.java

@@ -103,7 +103,7 @@ public class BCLibNetherBiomeSource extends BCLBiomeSource implements BiomeSourc
             } else {
                 BCLBiome bclBiome = BiomeAPI.getBiome(biomeID);
 
-                if (bclBiome != BCLBiomeRegistry.EMPTY_BIOME) {
+                if (!BCLBiomeRegistry.isEmptyBiome(bclBiome)) {
                     if (bclBiome.getParentBiome() == null) {
                         biomePicker.addBiome(bclBiome);
                     }

src/main/java/org/betterx/bclib/api/v2/generator/BiomePicker.java

@@ -112,7 +112,7 @@ public class BiomePicker {
                     subbiomes.add(create(b), w);
             });
 
-            if (bclBiome.getEdge() != null && isAllowed(bclBiome.getEdge())) {
+            if (bclBiome.hasEdge() && isAllowed(bclBiome.getEdge())) {
                 edge = create(bclBiome.getEdge());
             } else {
                 edge = null;

src/main/java/org/betterx/bclib/api/v2/generator/map/MapStack.java

@@ -89,6 +89,9 @@ public class MapStack implements BiomeMap {
                 for (int z = 0; z < side; z++) {
                     if (biomeMap[x][z] == null) {
                         BiomePicker.ActualBiome biome = chunks[i].getBiome(x, z);
+                        if (biome == null) {
+                            biome = chunks[i].getBiome(x, z);
+                        }
                         if (biome.bclBiome.isVertical()) {
                             biomeMap[x][z] = biome;
                             isNoEmpty = true;

src/main/java/org/betterx/bclib/api/v2/generator/map/hex/HexBiomeChunk.java

@@ -1,5 +1,6 @@
 package org.betterx.bclib.api.v2.generator.map.hex;
 
+import org.betterx.bclib.BCLib;
 import org.betterx.bclib.api.v2.generator.BiomePicker;
 import org.betterx.bclib.interfaces.BiomeChunk;
 
@@ -72,12 +73,22 @@ public class HexBiomeChunk implements BiomeChunk {
             outBuffer[getIndex(SIDE_MASK, index)] = outBuffer[getIndex(preN, index)];
         }
 
+        int lastAction = -1;
+        BiomePicker.ActualBiome lBiome = null;
         for (short index = 0; index < SIZE; index++) {
             if (outBuffer[index] == null) {
+                lastAction = 0;
+                lBiome = null;
                 outBuffer[index] = picker.getBiome(random);
             } else if (random.nextInt(4) == 0) {
+                lastAction = 1;
+                lBiome = outBuffer[index];
                 circle(outBuffer, index, outBuffer[index].getSubBiome(random), outBuffer[index]);
             }
+
+            if (outBuffer[index] == null) {
+                BCLib.LOGGER.error("Invalid Biome at " + index + ", " + lastAction + ", " + lBiome);
+            }
         }
 
         System.arraycopy(outBuffer, 0, this.biomes, 0, SIZE);

src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiome.java

@@ -1,18 +1,19 @@
 package org.betterx.bclib.api.v2.levelgen.biomes;
 
 import org.betterx.bclib.util.WeightedList;
+import org.betterx.worlds.together.world.event.WorldBootstrap;
 
 import com.mojang.datafixers.Products;
 import com.mojang.serialization.Codec;
 import com.mojang.serialization.codecs.RecordCodecBuilder;
 import net.minecraft.core.Registry;
+import net.minecraft.core.RegistryAccess;
 import net.minecraft.data.BuiltinRegistries;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.util.KeyDispatchDataCodec;
 import net.minecraft.world.level.biome.Biome;
 import net.minecraft.world.level.biome.Climate;
-import net.minecraft.world.level.levelgen.WorldgenRandom;
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
@@ -73,7 +74,7 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
                         .orElse(Optional.empty())
                         .forGetter((T o1) -> o1.edge == null
                                 ? Optional.empty()
-                                : Optional.of(o1.edge.biomeID));
+                                : Optional.of(o1.edge));
         public RecordCodecBuilder<T, ResourceLocation> t6 =
                 ResourceLocation.CODEC.fieldOf("biome")
                                       .forGetter((T o) -> ((BCLBiome) o).biomeID);
@@ -94,26 +95,7 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
                                                       ((BCLBiome) o1).biomeParent == null
                                                               ? Optional.empty()
                                                               : Optional.of(
-                                                                      ((BCLBiome) o1).biomeParent.biomeID));
+                                                                      ((BCLBiome) o1).biomeParent));
-        public RecordCodecBuilder<T, Optional<WeightedList<ResourceLocation>>> t9 =
-                WeightedList.listCodec(
-                                    ResourceLocation.CODEC,
-                                    "biomes",
-                                    "biome"
-                            )
-                            .optionalFieldOf("sub_biomes")
-                            .forGetter(
-                                    (T o) -> {
-                                        if (o.subbiomes == null
-                                                || o.subbiomes.isEmpty()
-                                                || (o.subbiomes.size() == 1 && o.subbiomes.contains(
-                                                o))) {
-                                            return Optional.empty();
-                                        }
-                                        return Optional.of(
-                                                o.subbiomes.map(
-                                                        b -> b.biomeID));
-                                    });
         public RecordCodecBuilder<T, Optional<String>> t10 =
                 Codec.STRING.optionalFieldOf("intended_for")
                             .orElse(Optional.of(BiomeAPI.BiomeType.NONE.getName()))
@@ -123,52 +105,51 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
                                             : Optional.of(((BCLBiome) o).intendedType.getName()));
     }
 
-    public static <T extends BCLBiome, P12> Products.P12<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<WeightedList<ResourceLocation>>, Optional<String>, P12> codecWithSettings(
+    public static <T extends BCLBiome, P11> Products.P11<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<String>, P11> codecWithSettings(
             RecordCodecBuilder.Instance<T> instance,
+            final RecordCodecBuilder<T, P11> p11
+    ) {
+        CodecAttributes<T> a = new CodecAttributes<>();
+        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t10, p11);
+    }
+
+    public static <T extends BCLBiome, P11, P12> Products.P12<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<String>, P11, P12> codecWithSettings(
+            RecordCodecBuilder.Instance<T> instance,
+            final RecordCodecBuilder<T, P11> p11,
             final RecordCodecBuilder<T, P12> p12
     ) {
         CodecAttributes<T> a = new CodecAttributes<>();
-        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t9, a.t10, p12);
+        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t10, p11, p12);
     }
 
-    public static <T extends BCLBiome, P12, P13> Products.P13<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<WeightedList<ResourceLocation>>, Optional<String>, P12, P13> codecWithSettings(
+    public static <T extends BCLBiome, P11, P12, P13, P14> Products.P14<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<String>, P11, P12, P13, P14> codecWithSettings(
-            RecordCodecBuilder.Instance<T> instance,
-            final RecordCodecBuilder<T, P12> p12,
-            final RecordCodecBuilder<T, P13> p13
-    ) {
-        CodecAttributes<T> a = new CodecAttributes<>();
-        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t9, a.t10, p12, p13);
-    }
-
-    public static <T extends BCLBiome, P12, P13, P14, P15> Products.P15<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<WeightedList<ResourceLocation>>, Optional<String>, P12, P13, P14, P15> codecWithSettings(
-            RecordCodecBuilder.Instance<T> instance,
-            final RecordCodecBuilder<T, P12> p12,
-            final RecordCodecBuilder<T, P13> p13,
-            final RecordCodecBuilder<T, P14> p14,
-            final RecordCodecBuilder<T, P15> p15
-    ) {
-        CodecAttributes<T> a = new CodecAttributes<>();
-        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t9, a.t10, p12, p13, p14, p15);
-    }
-
-    public static <T extends BCLBiome, P12, P13, P14> Products.P14<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<WeightedList<ResourceLocation>>, Optional<String>, P12, P13, P14> codecWithSettings(
             RecordCodecBuilder.Instance<T> instance,
+            final RecordCodecBuilder<T, P11> p11,
             final RecordCodecBuilder<T, P12> p12,
             final RecordCodecBuilder<T, P13> p13,
             final RecordCodecBuilder<T, P14> p14
     ) {
         CodecAttributes<T> a = new CodecAttributes<>();
-        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t9, a.t10, p12, p13, p14);
+        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t10, p11, p12, p13, p14);
     }
 
-    public static <T extends BCLBiome> Products.P11<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<WeightedList<ResourceLocation>>, Optional<String>> codecWithSettings(
+    public static <T extends BCLBiome, P11, P12, P13> Products.P13<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<String>, P11, P12, P13> codecWithSettings(
+            RecordCodecBuilder.Instance<T> instance,
+            final RecordCodecBuilder<T, P11> p11,
+            final RecordCodecBuilder<T, P12> p12,
+            final RecordCodecBuilder<T, P13> p13
+    ) {
+        CodecAttributes<T> a = new CodecAttributes<>();
+        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t10, p11, p12, p13);
+    }
+
+    public static <T extends BCLBiome> Products.P10<RecordCodecBuilder.Mu<T>, Float, Float, Float, Integer, Boolean, Optional<ResourceLocation>, ResourceLocation, Optional<List<Climate.ParameterPoint>>, Optional<ResourceLocation>, Optional<String>> codecWithSettings(
             RecordCodecBuilder.Instance<T> instance
     ) {
         CodecAttributes<T> a = new CodecAttributes<>();
-        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t9, a.t10);
+        return instance.group(a.t0, a.t1, a.t2, a.t3, a.t4, a.t5, a.t6, a.t7, a.t8, a.t10);
     }
 
-    protected final WeightedList<BCLBiome> subbiomes = new WeightedList<>();
     private final Map<String, Object> customData = Maps.newHashMap();
     private final ResourceLocation biomeID;
     private final ResourceKey<Biome> biomeKey;
@@ -176,7 +157,7 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
 
     protected final List<Climate.ParameterPoint> parameterPoints = Lists.newArrayList();
 
-    private BCLBiome biomeParent;
+    private ResourceLocation biomeParent;
 
     private BiomeAPI.BiomeType intendedType = BiomeAPI.BiomeType.NONE;
 
@@ -190,30 +171,15 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
             ResourceLocation biomeID,
             Optional<List<Climate.ParameterPoint>> parameterPoints,
             Optional<ResourceLocation> biomeParent,
-            Optional<WeightedList<ResourceLocation>> subbiomes,
             Optional<String> intendedType
     ) {
         super(terrainHeight, fogDensity, genChance, edgeSize, vertical, edge.map(BiomeAPI::getBiome).orElse(null));
         biomeToRegister = null;
         this.biomeID = biomeID;
         this.biomeKey = ResourceKey.create(Registry.BIOME_REGISTRY, biomeID);
-        if (subbiomes.isEmpty() || subbiomes.get().size() == 0) {
+        this.biomeParent = biomeParent.orElse(null);
-            this.subbiomes.add(this, 1);
-        } else {
-            this.subbiomes.addAll(subbiomes.get().map(BiomeAPI::getBiome));
-        }
-        this.biomeParent = biomeParent.map(BiomeAPI::getBiome).orElse(null);
         if (parameterPoints.isPresent()) this.parameterPoints.addAll(parameterPoints.get());
         this.setIntendedType(intendedType.map(t -> BiomeAPI.BiomeType.create(t)).orElse(BiomeAPI.BiomeType.NONE));
-
-        //make sure we are registered properly
-        if (this.biomeParent != null)
-            this.biomeParent.addSubBiome(this);
-
-        //make sure edges are set up correct
-        if (this.edge != null) {
-            this.setEdge(this.edge);
-        }
     }
 
     /**
@@ -289,7 +255,6 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      */
     protected BCLBiome(ResourceKey<Biome> biomeKey, Biome biomeToRegister, BCLBiomeSettings defaults) {
         this.biomeToRegister = biomeToRegister;
-        this.subbiomes.add(this, 1.0F);
         this.biomeID = biomeKey.location();
         this.biomeKey = biomeKey;
 
@@ -324,7 +289,11 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      */
     @Nullable
     public BCLBiome getEdge() {
-        return edge;
+        return BiomeAPI.getBiome(edge);
+    }
+
+    public boolean hasEdge() {
+        return !BCLBiomeRegistry.isEmptyBiome(edge);
     }
 
     /**
@@ -333,9 +302,8 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      * @param edge {@link BCLBiome} as the edge biome.
      * @return same {@link BCLBiome}.
      */
-    BCLBiome setEdge(BCLBiome edge) {
+    BCLBiome setEdge(ResourceLocation edge) {
         this.edge = edge;
-        edge.biomeParent = this;
         return this;
     }
 
@@ -348,9 +316,10 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      */
     public BCLBiome addEdge(BCLBiome edge) {
         if (this.edge != null) {
-            this.edge.addSubBiome(edge);
+            this.setEdge(edge.biomeID);
+            edge.biomeParent = edge.biomeID;
         } else {
-            this.setEdge(edge);
+            this.setEdge((ResourceLocation) null);
         }
         return this;
     }
@@ -363,19 +332,26 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      * @return same {@link BCLBiome}.
      */
     public BCLBiome addSubBiome(BCLBiome biome) {
-        biome.biomeParent = this;
+        biome.biomeParent = this.biomeID;
-        subbiomes.add(biome, biome.getGenChance());
         return this;
     }
 
-    /**
+    private WeightedList<BCLBiome> getSubBiomes() {
-     * Checks if specified biome is a sub-biome of this one.
+        RegistryAccess acc = WorldBootstrap.getLastRegistryAccess();
-     *
+        WeightedList<BCLBiome> subbiomes = new WeightedList<>();
-     * @param biome {@link Random}.
+        subbiomes.add(this, 1.0f);
-     * @return true if this instance contains specified biome as a sub-biome.
+        if (acc == null) return subbiomes;
-     */
+
-    public boolean containsSubBiome(BCLBiome biome) {
+        Registry<BCLBiome> reg = acc.registryOrThrow(BCLBiomeRegistry.BCL_BIOMES_REGISTRY);
-        return subbiomes.contains(biome);
+
+        for (Map.Entry<ResourceKey<BCLBiome>, BCLBiome> entry : reg.entrySet()) {
+            BCLBiome b = entry.getValue();
+            if (this.biomeID.equals(entry.getValue().biomeParent)) {
+                subbiomes.add(b, b.genChance);
+            }
+        }
+
+        return subbiomes;
     }
 
     /**
@@ -384,11 +360,11 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      * @param random {@link Random}.
      * @return {@link BCLBiome}.
      */
-    public BCLBiome getSubBiome(WorldgenRandom random) {
+//    public BCLBiome getSubBiome(WorldgenRandom random) {
-        return subbiomes.get(random);
+//        return getSubBiomes().get(random);
-    }
+//    }
-
     public void forEachSubBiome(BiConsumer<BCLBiome, Float> consumer) {
+        final WeightedList<BCLBiome> subbiomes = getSubBiomes();
         for (int i = 0; i < subbiomes.size(); i++)
             consumer.accept(subbiomes.get(i), subbiomes.getWeight(i));
     }
@@ -400,7 +376,11 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      */
     @Nullable
     public BCLBiome getParentBiome() {
-        return this.biomeParent;
+        return BiomeAPI.getBiome(this.biomeParent);
+    }
+
+    public boolean hasParentBiome() {
+        return !BCLBiomeRegistry.isEmptyBiome(biomeParent);
     }
 
     /**
@@ -410,7 +390,7 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
      * @return true if biome or its parent is same.
      */
     public boolean isSame(BCLBiome biome) {
-        return biome == this || (biome.biomeParent != null && biome.biomeParent == this);
+        return biome == this || (biome.biomeParent != null && biome.biomeParent.equals(this.biomeID));
     }
 
     /**
@@ -422,6 +402,7 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
         return biomeID;
     }
 
+
     /**
      * Getter for biomeKey
      *
@@ -488,8 +469,9 @@ public class BCLBiome extends BCLBiomeSettings implements BiomeData {
     private final boolean didLoadConfig = false;
 
     public boolean isEdgeBiome() {
-        if (getParentBiome() == null) return false;
+        final BCLBiome parent = getParentBiome();
-        return getParentBiome().edge == this;
+        if (parent == null) return false;
+        return this.biomeID.equals(parent.edge);
     }
 
     boolean allowFabricRegistration() {

src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeRegistry.java

@@ -42,6 +42,14 @@ public class BCLBiomeRegistry {
      **/
     public static final BCLBiome EMPTY_BIOME = new BCLBiome(Biomes.THE_VOID.location());
 
+    public static boolean isEmptyBiome(ResourceLocation l) {
+        return l == null || Biomes.THE_VOID.location().equals(l);
+    }
+
+    public static boolean isEmptyBiome(BCLBiome b) {
+        return b == null || b == EMPTY_BIOME;
+    }
+
     /**
      * Register a codec for a custom subclass of {@link BCLBiome}. Each subclass needs to provide
      * a codec, otherwise the instance will get rebuild as a regular BCLib biome loosing the Type
@@ -134,9 +142,9 @@ public class BCLBiomeRegistry {
         return getOrElseEmpty(WorldBootstrap.getLastRegistryAccess(), loc);
     }
 
-    public static BCLBiome getOrElseEmpty(@Nullable RegistryAccess access, ResourceLocation loc) {
+    public static @Nullable BCLBiome getOrElseEmpty(@Nullable RegistryAccess access, ResourceLocation loc) {
         BCLBiome res = access == null ? null : get(access, loc);
-        if (res == null) return EMPTY_BIOME;
+        //if (res == null) return EMPTY_BIOME;
         return res;
     }
 

src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeSettings.java

@@ -3,6 +3,7 @@ package org.betterx.bclib.api.v2.levelgen.biomes;
 import org.betterx.bclib.api.v2.generator.BiomePicker;
 import org.betterx.bclib.config.Configs;
 
+import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.level.biome.Biome;
 
 public class BCLBiomeSettings {
@@ -87,7 +88,7 @@ public class BCLBiomeSettings {
          * @return same {@link Builder}.
          */
         public R setEdge(BCLBiome edge) {
-            storage.edge = edge;
+            storage.edge = edge == null ? null : edge.getID();
             return (R) this;
         }
 
@@ -116,7 +117,7 @@ public class BCLBiomeSettings {
         this.genChance = genChance;
         this.edgeSize = edgeSize;
         this.vertical = vertical;
-        this.edge = edge;
+        this.edge = edge == null ? null : edge.getID();
     }
 
     protected BCLBiomeSettings() {
@@ -133,7 +134,7 @@ public class BCLBiomeSettings {
     float genChance;
     int edgeSize;
     boolean vertical;
-    BCLBiome edge;
+    ResourceLocation edge;
 
 
     /**
@@ -187,7 +188,7 @@ public class BCLBiomeSettings {
      * @return The assigned edge biome.
      */
     public BCLBiome getEdge() {
-        return edge;
+        return BiomeAPI.getBiome(edge);
     }
 
     /**

src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BiomeAPI.java

@@ -554,7 +554,7 @@ public class BiomeAPI {
      * @return {@link BCLBiome} or {@code BiomeAPI.EMPTY_BIOME}.
      */
     public static BCLBiome getBiome(ResourceLocation biomeID) {
-        if (biomeID == null) return BCLBiomeRegistry.EMPTY_BIOME;
+        if (biomeID == null) return null;
         return BCLBiomeRegistry.getOrElseEmpty(biomeID);
     }
 
@@ -618,9 +618,11 @@ public class BiomeAPI {
     }
 
     public static boolean wasRegisteredAs(ResourceLocation biomeID, BiomeType dim) {
-        if (BCLBiomeRegistry.EMPTY_BIOME.getID().equals(biomeID))
+        if (BCLBiomeRegistry.isEmptyBiome(biomeID))
             return false;
-        return BCLBiomeRegistry.getOrElseEmpty(biomeID).getIntendedType().is(dim);
+        final BCLBiome res = BCLBiomeRegistry.getOrElseEmpty(biomeID);
+        if (res == null) return false;
+        return res.getIntendedType().is(dim);
     }
 
     public static boolean wasRegisteredAsNetherBiome(ResourceLocation biomeID) {

src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/InternalBiomeAPI.java

@@ -264,7 +264,7 @@ public class InternalBiomeAPI {
             BiomeAPI.BiomeType type
     ) {
         BCLBiome bclBiome = BiomeAPI.getBiome(biomeKey.location());
-        if (bclBiome == BCLBiomeRegistry.EMPTY_BIOME) {
+        if (BCLBiomeRegistry.isEmptyBiome(bclBiome)) {
             bclBiome = new BCLBiome(biomeKey, setings);
             bclBiome._setIntendedType(type);
         }
@@ -281,7 +281,7 @@ public class InternalBiomeAPI {
                         .event(oBiomeRegistry.get())
                         .register((rawId, id, biome) -> {
                             BCLBiome b = BiomeAPI.getBiome(id);
-                            if (!"minecraft".equals(id.getNamespace()) && (b == null || b == BCLBiomeRegistry.EMPTY_BIOME)) {
+                            if (!"minecraft".equals(id.getNamespace()) && BCLBiomeRegistry.isEmptyBiome(b)) {
                                 //BCLib.LOGGER.info(" #### " + rawId + ", " + biome + ", " + id);
                                 //BIOMES_TO_SORT.add(id);
 //                            BIOME_ADDITIONS.computeIfAbsent(oBiomeRegistry.get(), reg -> new AtomicInteger(0))

src/main/java/org/betterx/bclib/client/render/CustomFogRenderer.java

@@ -117,12 +117,15 @@ public class CustomFogRenderer {
 
     private static boolean shouldIgnore(Level level, int x, int y, int z) {
         Biome biome = level.getBiome(MUT_POS.set(x, y, z)).value();
-        return BiomeAPI.getRenderBiome(biome) == BCLBiomeRegistry.EMPTY_BIOME;
+        return BCLBiomeRegistry.isEmptyBiome(BiomeAPI.getRenderBiome(biome));
     }
 
     private static float getFogDensityI(Level level, int x, int y, int z) {
         Biome biome = level.getBiome(MUT_POS.set(x, y, z)).value();
         BCLBiome renderBiome = BiomeAPI.getRenderBiome(biome);
+        if (renderBiome == null) {
+            return BCLBiomeRegistry.EMPTY_BIOME.getFogDensity();
+        }
         return renderBiome.getFogDensity();
     }
 

src/main/java/org/betterx/bclib/util/WeightedList.java

@@ -85,7 +85,7 @@ public class WeightedList<T> {
      * @return {@link T} value.
      */
     public T get(RandomSource random) {
-        if (maxWeight < 1) {
+        if (maxWeight <= 0) {
             return null;
         }
         float weight = random.nextFloat() * maxWeight;