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

This reverts commit 4f55c8d8

cura/CuraApplication.py

@@ -4,7 +4,7 @@
 import os
 import sys
 import time
-from typing import cast, TYPE_CHECKING, Optional, Callable, List, Any
+from typing import cast, TYPE_CHECKING, Optional, Callable, List, Any, Dict
 
 import numpy
 from PyQt5.QtCore import QObject, QTimer, QUrl, pyqtSignal, pyqtProperty, QEvent, Q_ENUMS
@@ -1382,12 +1382,21 @@ class CuraApplication(QtApplication):
         if not nodes:
             return
 
+        objects_in_filename = {}  # type: Dict[str, List[CuraSceneNode]]
         for node in nodes:
             mesh_data = node.getMeshData()
-
             if mesh_data:
                 file_name = mesh_data.getFileName()
                 if file_name:
+                    if file_name not in objects_in_filename:
+                        objects_in_filename[file_name] = []
+                    if file_name in objects_in_filename:
+                        objects_in_filename[file_name].append(node)
+                else:
+                    Logger.log("w", "Unable to reload data because we don't have a filename.")
+
+        for file_name, nodes in objects_in_filename.items():
+            for node in nodes:
                 job = ReadMeshJob(file_name)
                 job._node = node  # type: ignore
                 job.finished.connect(self._reloadMeshFinished)
@@ -1395,8 +1404,6 @@ class CuraApplication(QtApplication):
                     job.finished.connect(self.updateOriginOfMergedMeshes)
 
                 job.start()
-                else:
-                    Logger.log("w", "Unable to reload data because we don't have a filename.")
 
     @pyqtSlot("QStringList")
     def setExpandedCategories(self, categories: List[str]) -> None:
@@ -1572,13 +1579,30 @@ class CuraApplication(QtApplication):
     fileLoaded = pyqtSignal(str)
     fileCompleted = pyqtSignal(str)
 
-    def _reloadMeshFinished(self, job):
+    def _reloadMeshFinished(self, job) -> None:
-        # TODO; This needs to be fixed properly. We now make the assumption that we only load a single mesh!
+        """
-        job_result = job.getResult()
+        Function called whenever a ReadMeshJob finishes in the background. It reloads a specific node object in the
+        scene from its source file. The function gets all the nodes that exist in the file through the job result, and
+        then finds the scene node that it wants to refresh by its object id. Each job refreshes only one node.
+
+        :param job: The ReadMeshJob running in the background that reads all the meshes in a file
+        :return: None
+        """
+        job_result = job.getResult()  # nodes that exist inside the file read by this job
         if len(job_result) == 0:
             Logger.log("e", "Reloading the mesh failed.")
             return
-        mesh_data = job_result[0].getMeshData()
+        object_found = False
+        mesh_data = None
+        # Find the node to be refreshed based on its id
+        for job_result_node in job_result:
+            if job_result_node.getId() == job._node.getId():
+                mesh_data = job_result_node.getMeshData()
+                object_found = True
+                break
+        if not object_found:
+            Logger.warning("The object with id {} no longer exists! Keeping the old version in the scene.".format(job_result_node.getId()))
+            return
         if not mesh_data:
             Logger.log("w", "Could not find a mesh in reloaded node.")
             return

plugins/3MFReader/ThreeMFReader.py

@@ -1,31 +1,28 @@
 # Copyright (c) 2019 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import List, Optional, Union, TYPE_CHECKING
 import os.path
 import zipfile
-
+from typing import List, Optional, Union, TYPE_CHECKING
-import numpy
 
 import Savitar
+import numpy
 
 from UM.Logger import Logger
 from UM.Math.Matrix import Matrix
 from UM.Math.Vector import Vector
 from UM.Mesh.MeshBuilder import MeshBuilder
 from UM.Mesh.MeshReader import MeshReader
+from UM.MimeTypeDatabase import MimeTypeDatabase, MimeType
 from UM.Scene.GroupDecorator import GroupDecorator
 from UM.Scene.SceneNode import SceneNode  # For typing.
-from UM.MimeTypeDatabase import MimeTypeDatabase, MimeType
-
 from cura.CuraApplication import CuraApplication
 from cura.Machines.ContainerTree import ContainerTree
-from cura.Settings.ExtruderManager import ExtruderManager
-from cura.Scene.CuraSceneNode import CuraSceneNode
 from cura.Scene.BuildPlateDecorator import BuildPlateDecorator
+from cura.Scene.CuraSceneNode import CuraSceneNode
 from cura.Scene.SliceableObjectDecorator import SliceableObjectDecorator
 from cura.Scene.ZOffsetDecorator import ZOffsetDecorator
-
+from cura.Settings.ExtruderManager import ExtruderManager
 
 try:
     if not TYPE_CHECKING:
@@ -52,7 +49,6 @@ 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 == "":
@@ -87,17 +83,20 @@ 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 == "":
-            node_name = "Object %s" % self._object_count
+            if file_name != "":
+                node_name = os.path.basename(file_name)
+            else:
+                node_name = "Object {}".format(node_id)
 
         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()
@@ -169,7 +168,6 @@ 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")