write custom action class to notify shape node about vbo changes

src/Mod/Part/Gui/SoBrepFaceSet.cpp

@@ -247,6 +247,12 @@ void SoBrepFaceSet::doAction(SoAction* action)
             }
         }
     }
+    // The recommended way to set 'updateVbo' is to reimplement the method 'notify'
+    // but the class made this method private so that we can't override it.
+    // So, the alternative way is to write a custom SoAction class.
+    else if (action->getTypeId() == Gui::SoUpdateVBOAction::getClassTypeId()) {
+        this->updateVbo = true;
+    }
 
     inherited::doAction(action);
 }

src/Mod/Part/Gui/SoBrepFaceSet.h

@@ -143,9 +143,7 @@ private:
 
     // Define some VBO pointer for the current mesh
     SbBool vboAvailable;
-public:
     SbBool updateVbo;
-private:
     uint32_t myvbo[2];
     SbBool vboLoaded;
     uint32_t indice_array;

src/Mod/Part/Gui/ViewProviderExt.cpp

@@ -106,6 +106,7 @@
 #include <App/Document.h>
 
 #include <Gui/SoFCUnifiedSelection.h>
+#include <Gui/SoFCSelectionAction.h>
 #include <Gui/Selection.h>
 #include <Gui/View3DInventorViewer.h>
 #include <Gui/Utilities.h>
@@ -800,8 +801,8 @@ void ViewProviderPartExt::reload()
 void ViewProviderPartExt::updateData(const App::Property* prop)
 {
     if (prop->getTypeId() == Part::PropertyPartShape::getClassTypeId()) {
-        // vejmarie: Force VBO update of the part
-        this->faceset->updateVbo = true;
+        Gui::SoUpdateVBOAction action;
+        action.apply(this->faceset);
 
         // get the shape to show
         const TopoDS_Shape &cShape = static_cast<const Part::PropertyPartShape*>(prop)->getValue();