HWND paint on widget is not visible through QGraphicsProxyWidget

Hi.

QGraphicsProxyWidget does not work with a widget that is painted on by our (old) video drivers. The embeded widget HWND/winId() is passed to the driver, and then to the underlying SDK. My understanding is that it doesn't know what the driver paint on it, so the proxy can't paint it either. From the Doc : widgets that wrap an external application or controller cannot be embedded.

Is there any known way to circumvent this issue ?

We tried to use the windows API to grab the widget's content, but it fails if the widget itself is not visible (it is possible that the drivers does not event draw on the widget/window, because it is not really visible).

You'll find attached screenshot and an example of the issue we face.

Thank you.