FEM: utils, add a method to get the Part to mesh

src/Mod/Fem/femtools/femutils.py

@@ -152,6 +152,23 @@ def get_pref_working_dir(solver_obj):
 
 
 # other
+def get_part_to_mesh(mesh_obj):
+    '''
+    gmsh mesh object: the Attribute is Part
+    netgen mesh object: the Attribute is Shape
+    other mesh objects: do not have a Attribute which holds the part to mesh
+    '''
+    if is_derived_from(mesh_obj, "Fem::FemMeshGmsh"):
+        return mesh_obj.Part
+    elif is_derived_from(mesh_obj, "Fem::FemMeshShapeNetgenObject"):
+        return mesh_obj.Shape
+    else:
+        return None
+    # TODO: the Attributes should be named with the same name
+    # should it be Shape or Part?
+    # IMHO Part since the Attributes references the document object and not a Shape
+
+
 def getBoundBoxOfAllDocumentShapes(doc):
     overalboundbox = None
     for o in doc.Objects: