Valid values:
"WxH", for example "640x480"
"fullscreen" to cover whole screen.
+ "scaled" to upscale the screen proportionally, letterboxing or pillarboxing.
+ "pixelperfect" to upscale by a whole-number factor (e.g. 2x or 3x size).
SDL_OMAP_BORDER_CUT:
This can be used to move parts of SDL surface out of screen, in other