* Remove some complexity. Surfaces currently include x and y offsets
  that are not longer used, removing these will make a lot of code easier to
  read. get_pixels and set_pixels currently use both the clip rects and
  the rect given as parameter. clip rects should be enough and it would
  simplify the code in glitz_pixel.c a bit.

* More YUV surface formats (YUY2, UYVY, I420..).

* Support for logical ops.

* Tiled bitmap geometry.

* API documentation.