When you draw a QPicture with some clipped parts (with setClipRect) inside a clipped rectangle RECT (also define with setClipRect), the QPicture non clipped parts are not clipped by RECT.

In the attached example, if you don't set clipped rectangle for red rectangle in the  QPicture, both red and blue rectangles are correctly clipped by the vertical band, but if you set a clipped rect for the red rectangle in the QPicture, the blue rectangle is no longer clipped.