I\'m writing a simulation of an embedded device\'s screen (which contains custom widgets on top of a main QWidget), and while the native size of the screen is 800x600, I wan
Bit of a guess here as I've not tried it... but you could try putting the top-level widget into a QGraphicsView then get the QGraphicsView to do the scaling.
You could then enable OpenGL on the QGraphicsView and have it scaled in hardware so it's nice and fast.