feat: add getAncestor method

thermion_dart/lib/thermion_dart/compatibility/native/thermion_dart.g.dart

@@ -1043,6 +1043,12 @@ external int get_parent(
   int child,
 );
 
+@ffi.Native<EntityId Function(ffi.Pointer<ffi.Void>, EntityId)>()
+external int get_ancestor(
+  ffi.Pointer<ffi.Void> sceneManager,
+  int child,
+);
+
 @ffi.Native<
     ffi.Void Function(ffi.Pointer<ffi.Void>, EntityId, EntityId, ffi.Bool)>()
 external void set_parent(

thermion_dart/lib/thermion_dart/thermion_viewer.dart

@@ -773,9 +773,14 @@ abstract class ThermionViewer {
       PrimitiveType primitiveType = PrimitiveType.TRIANGLES});
 
   ///
-  /// Gets the parent transform of [child].
+  /// Gets the parent entity of [entity]. Returns null if the entity has no parent. 
   ///
-  Future<ThermionEntity?> getParent(ThermionEntity child);
+  Future<ThermionEntity?> getParent(ThermionEntity entity);
+
+  ///
+  /// Gets the ancestor (ultimate parent) entity of [entity]. Returns null if the entity has no parent. 
+  ///
+  Future<ThermionEntity?> getAncestor(ThermionEntity entity);
 
   ///
   /// Sets the parent transform of [child] to [parent].

thermion_dart/lib/thermion_dart/thermion_viewer_ffi.dart

@@ -1805,6 +1805,21 @@ class ThermionViewerFFI extends ThermionViewer {
     return parent;
   }
 
+  ///
+  ///
+  ///
+  @override
+  Future<ThermionEntity?> getAncestor(ThermionEntity child) async {
+    if (_sceneManager == null) {
+      throw Exception("Asset manager must be non-null");
+    }
+    var parent = get_ancestor(_sceneManager!, child);
+    if (parent == _FILAMENT_ASSET_ERROR) {
+      return null;
+    }
+    return parent;
+  }
+
   ///
   ///
   ///

thermion_dart/test/integration_test.dart

@@ -124,7 +124,51 @@ void main() async {
     });
   });
 
-  group("transforms", () {
+  group("transforms & parenting", () {
+    test('getParent and getAncestor both return null when entity has no parent', () async {
+      var viewer = await createViewer();
+
+      final cube = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+
+      expect(await viewer.getParent(cube), isNull);
+      expect(await viewer.getAncestor(cube), isNull);
+    });
+
+    test(
+        'getParent returns the parent entity after one has been set via setParent',
+        () async {
+      var viewer = await createViewer();
+
+      final cube1 = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+      final cube2 = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+
+      await viewer.setParent(cube1, cube2);
+
+      final parent = await viewer.getParent(cube1);
+
+      expect(parent, cube2);
+    });
+
+    test('getAncestor returns the ultimate parent entity', () async {
+      var viewer = await createViewer();
+
+      final grandparent = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+      final parent = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+      final child = await viewer.createGeometry(cubeVertices, cubeIndices,
+          primitiveType: PrimitiveType.TRIANGLES);
+
+      await viewer.setParent(child, parent);
+      await viewer.setParent(parent, grandparent);
+
+      expect(await viewer.getAncestor(child), grandparent);
+
+    });
+
     test('set position based on screenspace coord', () async {
       var viewer = await createViewer();
       print(await viewer.getCameraFov(true));