PocketMatrix

I was considering modifying my game to be user selectable on running full screen or a smaller window (similar to what quake can do). I want the menu's and all to be the same, just the main game display to be smaller if they want (for performance issues).

The question is if the display->Clear is quicker than clearing three or four rectangles around the border of the "window" I always update.

The main "window" I speak of is always overwritten each frame, so I really don't need to clear that part. One would think that clearing only what you need would be faster, but I also think that the display->Clear routine is just a memset, so it may be faster to clear the whole thing than several subsets.

Any options or prior experience?

Thanks,
Jason