not sure how you're using the viewport command. if its just to clip images that are off screen then just use black images drawing on the borders? if its some sort of inset (like an animated hud or something) the only thing I can think of at the moment is doing a grab pixels:
- draw your hud off screen somewhere on the backbuffer.
- then do a grabImage of the size you want.
- then just draw that image where you want to on the screen.
- draw your hud off screen somewhere on the backbuffer.
- then do a grabImage of the size you want.
- then just draw that image where you want to on the screen.