I think adding transparent UI into the viewer is essential for CAD applications (HUD display, ocaf tree ect)
So I am trying to add transparent Qt widgets on the OpenGl viewer.
According to this http://doc.qt.digia.com/qq/qq26-openglcanvas.html you need to:
1. Subclass QGraphicsScene.
2. reimplement drawBackground() function.
3. Render your OpenGl scene in drawBackground().
4. Add transparent widgets to the scene.
This is straight forward except for step 3. drawBackground requires you to put in your (pure) OpenGl commands (Not view->Redraw(); )
So the question is, How can we render the viewer inside drawBackground(); ?
Is there a function that can be used to render like it does in the example?
I have attached a simple project of how it should be used.