fix(bop): Adds warning if hidden objects are given to bop writer

blenderproc/python/object/OnSurfaceSampler.py

@@ -34,6 +34,10 @@ def sample_poses_on_surface(objects_to_sample: List[MeshObject], surface: MeshOb
                                               else only the center of the object has to be above the surface
     :return: The list of placed objects.
     """
+    if len(set(objects_to_sample)) != len(objects_to_sample):
+        raise ValueError("The given list of objects to sample contains duplicates. "
+                         "This leads to complications in the sampling process.")
+
     if up_direction is None:
         up_direction = np.array([0., 0., 1.])
     else:

blenderproc/python/types/MeshObjectUtility.py

@@ -277,6 +277,13 @@ def hide(self, hide_object: bool = True):
         """
         self.blender_obj.hide_render = hide_object
 
+    def is_hidden(self) -> bool:
+        """ Returns whether the object is hidden in rendering.
+
+        :return: True, if it is hidden.
+        """
+        return self.blender_obj.hide_render
+
     def disable_rigidbody(self):
         """ Disables the rigidbody element of the object """
         if self.has_rigidbody_enabled():

blenderproc/python/writer/BopWriterUtility.py

@@ -77,14 +77,21 @@ def write_bop(output_dir: str, target_objects: Optional[List[MeshObject]] = None
     # Select target objects or objects from the specified dataset or all objects
     if target_objects is not None:
         dataset_objects = target_objects
+        for obj in get_all_mesh_objects():
+            if obj.is_hidden():
+                print(f"WARNING: The given object {obj.get_name()} is hidden. However, the bop writer will still add "
+                      "coco annotations for it. If this is not desired, don't pass the object to the bop writer.")
     elif dataset:
         dataset_objects = []
         for obj in get_all_mesh_objects():
-            if "bop_dataset_name" in obj.blender_obj and not obj.blender_obj.hide_render:
+            if "bop_dataset_name" in obj.blender_obj and not obj.is_hidden():
                 if obj.blender_obj["bop_dataset_name"] == dataset:
                     dataset_objects.append(obj)
     else:
-        dataset_objects = get_all_mesh_objects()
+        dataset_objects = []
+        for obj in get_all_mesh_objects():
+            if not obj.is_hidden():
+                dataset_objects.append(obj)
 
     # Check if there is any object from the specified dataset.
     if not dataset_objects: