Structures fix mixin

src/main/java/ru/betterend/mixin/common/ChunkSerializerMixin.java

@@ -0,0 +1,46 @@
+package ru.betterend.mixin.common;
+
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+
+import it.unimi.dsi.fastutil.longs.LongSet;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.LongArrayTag;
+import net.minecraft.structure.StructureStart;
+import net.minecraft.util.math.ChunkPos;
+import net.minecraft.world.ChunkSerializer;
+import net.minecraft.world.gen.feature.StructureFeature;
+
+@Mixin(ChunkSerializer.class)
+public class ChunkSerializerMixin {
+	@Overwrite
+	private static CompoundTag writeStructures(ChunkPos pos, Map<StructureFeature<?>, StructureStart<?>> structureStarts, Map<StructureFeature<?>, LongSet> structureReferences) {
+		CompoundTag tagResult = new CompoundTag();
+		CompoundTag tagStarts = new CompoundTag();
+		Iterator<Entry<StructureFeature<?>, StructureStart<?>>> startsIterator = structureStarts.entrySet().iterator();
+
+		while (startsIterator.hasNext()) {
+			Entry<StructureFeature<?>, StructureStart<?>> start = startsIterator.next();
+			tagStarts.put((start.getKey()).getName(), (start.getValue()).toTag(pos.x, pos.z));
+		}
+
+		tagResult.put("Starts", tagStarts);
+		CompoundTag tagReferences = new CompoundTag();
+		Iterator<Entry<StructureFeature<?>, LongSet>> refIterator = structureReferences.entrySet().iterator();
+
+		while (refIterator.hasNext()) {
+			Entry<StructureFeature<?>, LongSet> feature = refIterator.next();
+			// Structures sometimes can be null
+			if (feature.getKey() != null) {
+				tagReferences.put((feature.getKey()).getName(), new LongArrayTag(feature.getValue()));
+			}
+		}
+
+		tagResult.put("References", tagReferences);
+		return tagResult;
+	}
+}

src/main/resources/betterend.mixins.common.json

@@ -13,6 +13,7 @@
 		"ChorusFlowerBlockMixin",
 		"ChorusPlantBlockMixin",
 		"RecipeManagerAccessor",
+		"ChunkSerializerMixin",
 		"MinecraftServerMixin",
 		"TagGroupLoaderMixin",
 		"EndermanEntityMixin",