Fem: Add property to set pipeline and filters color if Field is None - fixes #21352

src/Mod/Fem/Gui/Command.cpp

@@ -2089,6 +2089,18 @@ void setupFilter(Gui::Command* cmd, std::string Name)
     auto objFilter = App::GetApplication().getActiveDocument()->getActiveObject();
     auto femFilter = static_cast<Fem::FemPostFilter*>(objFilter);
 
+    auto selObjectView = static_cast<FemGui::ViewProviderFemPostObject*>(
+        Gui::Application::Instance->getViewProvider(selObject)
+    );
+    // use none field color from base filter
+    Base::color_traits<Base::Color> ct {selObjectView->NoneFieldColor.getValue()};
+    cmd->doCommand(
+        Gui::Command::Doc,
+        "App.activeDocument().ActiveObject.ViewObject.NoneFieldColor = (%d, %d, %d)",
+        ct.red(),
+        ct.green(),
+        ct.blue()
+    );
     // TODO: FIX
     /*
     auto selObjectView = static_cast<FemGui::ViewProviderFemPostObject*>(

src/Mod/Fem/Gui/ViewProviderFemPostObject.cpp

@@ -166,6 +166,13 @@ ViewProviderFemPostObject::ViewProviderFemPostObject()
         App::Prop_None,
         "Set wireframe line color."
     );
+    ADD_PROPERTY_TYPE(
+        NoneFieldColor,
+        (0.8f, 0.8f, 0.8f),
+        "Object Style",
+        App::Prop_None,
+        "Shape color used if Field property is None."
+    );
     ADD_PROPERTY_TYPE(
         PlainColorEdgeOnSurface,
         (false),
@@ -689,7 +696,8 @@ void ViewProviderFemPostObject::WriteColorData(bool ResetColorBarRange)
     }
 
     if (Field.getEnumVector().empty() || Field.getValue() == 0) {
-        m_material->diffuseColor.setValue(SbColor(0.8, 0.8, 0.8));
+        Base::Color cNone = NoneFieldColor.getValue();
+        m_material->diffuseColor.setValue(SbColor(cNone.r, cNone.g, cNone.b));
         float trans = Base::fromPercent(Transparency.getValue());
         m_material->transparency.setValue(trans);
         m_materialBinding->value = SoMaterialBinding::OVERALL;
@@ -867,6 +875,9 @@ void ViewProviderFemPostObject::onChanged(const App::Property* prop)
         int child = plainColor ? 1 : 0;
         m_switchMatEdges->whichChild.setValue(child);
     }
+    else if (prop == &NoneFieldColor) {
+        WriteColorData(ResetColorBarRange);
+    }
 
     ViewProviderDocumentObject::onChanged(prop);
 }

src/Mod/Fem/Gui/ViewProviderFemPostObject.h

@@ -84,6 +84,7 @@ public:
     App::PropertyPercent Transparency;
     App::PropertyBool PlainColorEdgeOnSurface;
     App::PropertyColor EdgeColor;
+    App::PropertyColor NoneFieldColor;
     App::PropertyFloatConstraint LineWidth;
     App::PropertyFloatConstraint PointSize;
 

src/Mod/Fem/femcommands/manager.py

@@ -406,6 +406,9 @@ class CommandManager:
         FreeCADGui.doCommand(
             'FreeCAD.ActiveDocument.ActiveObject.ViewObject.SelectionStyle = "BoundBox"'
         )
+        FreeCADGui.doCommand(
+            f"FreeCAD.ActiveDocument.ActiveObject.ViewObject.NoneFieldColor = {self.selobj.ViewObject.NoneFieldColor}"
+        )
 
         # hide selected filter
         FreeCADGui.doCommand(