[1.17.1+ Fix] Entity collision and raytrace

src/main/java/cam72cam/mod/mixin/fix/large_entity_collision/MixinEntitySectionStorage.java

@@ -0,0 +1,46 @@
+package cam72cam.mod.mixin.fix.large_entity_collision;
+
+import cam72cam.mod.entity.ModdedEntity;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import net.minecraft.world.level.entity.EntityAccess;
+import net.minecraft.world.level.entity.EntitySection;
+import net.minecraft.world.level.entity.EntitySectionStorage;
+import net.minecraft.world.phys.AABB;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import java.util.function.Consumer;
+
+
+/**
+ * Fixes collision detection and ray tracing for entities that span multiple chunks.
+ * <p>
+ * Since Minecraft 1.17, the game only checks for entities within the chunks that the
+ * given bounding box intersects. This causes issues with large entities that extend beyond
+ * their primary chunk, as parts of them in other chunks may be ignored during collision
+ * detection and ray tracing operations.
+ * <p>
+ * This mixin adds a check specifically for our {@link ModdedEntity} instances
+ * to ensure that all relevant entity sections are considered, restoring proper functionality
+ * for large entities that cross chunk boundaries.
+ */
+@Mixin(EntitySectionStorage.class)
+public class MixinEntitySectionStorage<T extends EntityAccess>  {
+    @Shadow
+    @Final
+    private Long2ObjectMap<EntitySection<T>> sections;
+
+    @Inject(method = "forEachAccessibleSection", at = @At("TAIL"))
+    public void inject(AABB pBoundingBox, Consumer<EntitySection<T>> pSection, CallbackInfo ci) {
+        this.sections.values().stream()
+                     .filter(e -> e.getStatus().isAccessible())
+                     .filter(e -> e.storage.find(ModdedEntity.class)
+                                                          .stream()
+                                                          .anyMatch(m -> m.getBoundingBox().intersects(pBoundingBox)))
+                     .forEach(pSection);
+    }
+}

src/main/resources/META-INF/accesstransformer.cfg

@@ -4,4 +4,5 @@ public net.minecraft.server.MinecraftServer f_129744_ # storageSource
 public net.minecraft.server.packs.FolderPackResources m_10281_(Ljava/lang/String;)Ljava/io/File; # getFile
 public net.minecraft.server.level.ChunkMap m_140416_()Ljava/lang/Iterable; # getChunks
 public-f net.minecraft.world.entity.Entity m_142469_()Lnet/minecraft/world/phys/AABB; # net/minecraft/world/entity/Entity/getBoundingBox ()Lnet/minecraft/world/phys/AABB
-public net.minecraft.client.multiplayer.ClientLevel f_104561_ #connection
+public net.minecraft.client.multiplayer.ClientLevel f_104561_ #connection
+public net.minecraft.world.level.entity.EntitySection f_156827_ # storage

src/main/resources/mixins.universalmodcore.fix.json

@@ -0,0 +1,19 @@
+{
+  "required": true,
+  "package": "cam72cam.mod.mixin.fix",
+  "refmap": "mixins.universalmodcore.refmap.json",
+  "target": "@env(DEFAULT)",
+  "minVersion": "0.8.2",
+  "compatibilityLevel": "JAVA_16",
+  "mixins": [
+    "large_entity_collision.MixinEntitySectionStorage"
+  ],
+  "client": [
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  },
+  "overwrites": {
+    "requireAnnotations": true
+  }
+}