CURA-4772 Create a CuraSceneNode instead of a SceneNode when reading a

GCode. Avoid creating an empty CuraSceneNode if the node is already an
instance of it.

plugins/GCodeReader/FlavorParser.py

@@ -8,14 +8,14 @@ from UM.Logger import Logger
 from UM.Math.AxisAlignedBox import AxisAlignedBox
 from UM.Math.Vector import Vector
 from UM.Message import Message
-from UM.Scene.SceneNode import SceneNode
+from cura.Scene.CuraSceneNode import CuraSceneNode
 from UM.i18n import i18nCatalog
 from UM.Preferences import Preferences
 
 catalog = i18nCatalog("cura")
 
 from cura import LayerDataBuilder
-from cura import LayerDataDecorator
+from cura.LayerDataDecorator import LayerDataDecorator
 from cura.LayerPolygon import LayerPolygon
 from cura.Scene.GCodeListDecorator import GCodeListDecorator
 from cura.Settings.ExtruderManager import ExtruderManager
@@ -292,7 +292,7 @@ class FlavorParser:
         # We obtain the filament diameter from the selected printer to calculate line widths
         self._filament_diameter = Application.getInstance().getGlobalContainerStack().getProperty("material_diameter", "value")
 
-        scene_node = SceneNode()
+        scene_node = CuraSceneNode()
         # Override getBoundingBox function of the sceneNode, as this node should return a bounding box, but there is no
         # real data to calculate it from.
         scene_node.getBoundingBox = self._getNullBoundingBox
@@ -422,7 +422,7 @@ class FlavorParser:
         material_color_map[0, :] = [0.0, 0.7, 0.9, 1.0]
         material_color_map[1, :] = [0.7, 0.9, 0.0, 1.0]
         layer_mesh = self._layer_data_builder.build(material_color_map)
-        decorator = LayerDataDecorator.LayerDataDecorator()
+        decorator = LayerDataDecorator()
         decorator.setLayerData(layer_mesh)
         scene_node.addDecorator(decorator)