Revert "Merge pull request #7384 from Ultimaker/CURA-7333_Fix_reloading_3mf_files_with_many_objects"

This reverts commit 3e46489b6b, reversing
changes made to f5669a5a27.

plugins/3MFReader/ThreeMFReader.py

@@ -52,6 +52,7 @@ class ThreeMFReader(MeshReader):
         self._root = None
         self._base_name = ""
         self._unit = None
+        self._object_count = 0  # Used to name objects as there is no node name yet.
 
     def _createMatrixFromTransformationString(self, transformation: str) -> Matrix:
         if transformation == "":
@@ -86,20 +87,17 @@ class ThreeMFReader(MeshReader):
     ##  Convenience function that converts a SceneNode object (as obtained from libSavitar) to a scene node.
     #   \returns Scene node.
     def _convertSavitarNodeToUMNode(self, savitar_node: Savitar.SceneNode, file_name: str = "") -> Optional[SceneNode]:
+        self._object_count += 1
+
         node_name = savitar_node.getName()
-        node_id = savitar_node.getId()
         if node_name == "":
-            if file_name != "":
-                node_name = os.path.basename(file_name)
-            else:
-                node_name = "Object {}".format(node_id)
+            node_name = "Object %s" % self._object_count
 
         active_build_plate = CuraApplication.getInstance().getMultiBuildPlateModel().activeBuildPlate
 
         um_node = CuraSceneNode() # This adds a SettingOverrideDecorator
         um_node.addDecorator(BuildPlateDecorator(active_build_plate))
         um_node.setName(node_name)
-        um_node.setId(node_id)
         transformation = self._createMatrixFromTransformationString(savitar_node.getTransformation())
         um_node.setTransformation(transformation)
         mesh_builder = MeshBuilder()
@@ -171,6 +169,7 @@ class ThreeMFReader(MeshReader):
 
     def _read(self, file_name: str) -> Union[SceneNode, List[SceneNode]]:
         result = []
+        self._object_count = 0  # Used to name objects as there is no node name yet.
         # The base object of 3mf is a zipped archive.
         try:
             archive = zipfile.ZipFile(file_name, "r")