FEM: set mesh color, use proper return values for python API

src/Mod/Fem/FemTools.py

@@ -83,7 +83,9 @@ class FemTools(QtCore.QRunnable, QtCore.QObject):
             if self.mesh:
                 self.mesh.ViewObject.NodeColor = {}
                 self.mesh.ViewObject.ElementColor = {}
-                self.mesh.ViewObject.setNodeColorByScalars()
+                node_numbers = self.mesh.FemMesh.Nodes.keys()
+                zero_values = [0] * len(node_numbers)
+                self.mesh.ViewObject.setNodeColorByScalars(node_numbers, zero_values)
 
     ## Resets mesh color, deformation and removes all result objects if preferences to keep them is not set
     #  @param self The python object self

src/Mod/Fem/Gui/ViewProviderFemMeshPyImp.cpp

@@ -96,6 +96,7 @@ PyObject* ViewProviderFemMeshPy::setNodeColorByScalars(PyObject *args)
         this->getViewProviderFemMeshPtr()->setColorByNodeId(ids, node_colors);
     } else {
         PyErr_SetString(Base::BaseExceptionFreeCADError, "PyArg_ParseTuple failed. Invalid arguments used with setNodeByScalars");
+        return 0;
     }
     Py_Return;
 }
@@ -124,6 +125,7 @@ PyObject* ViewProviderFemMeshPy::setNodeDisplacementByVectors(PyObject *args)
         this->getViewProviderFemMeshPtr()->setDisplacementByNodeId(ids, vectors);
     } else {
         PyErr_SetString(Base::BaseExceptionFreeCADError, "PyArg_ParseTuple failed. Invalid arguments used with setNodeDisplacementByVectors");
+        return 0;
     }
     Py_Return;
 }

src/Mod/Fem/PyGui/_TaskPanelFemResultShow.py

@@ -417,7 +417,9 @@ class _TaskPanelFemResultShow:
     def reset_mesh_color(self):
         self.mesh_obj.ViewObject.NodeColor = {}
         self.mesh_obj.ViewObject.ElementColor = {}
-        self.mesh_obj.ViewObject.setNodeColorByScalars()
+        node_numbers = self.mesh_obj.FemMesh.Nodes.keys()
+        zero_values = [0] * len(node_numbers)
+        self.mesh_obj.ViewObject.setNodeColorByScalars(node_numbers, zero_values)
 
     def reject(self):
         FreeCADGui.Control.closeDialog()  # if the taks panell is called from Command obj is not in edit mode thus reset edit does not cleses the dialog, may be do not call but set in edit instead