US Patent 7542042 Subpicture overlay using fragment shader

A new method of operating a fragment shader to produce complex video content comprised of a video image or images, such as from a DVD player, that overlays a fragment shader-processed background. Pixels are fragment shader-processed during one loop or set of loops through a texture processing stations to produce a fragment shader-processed background. Then, at least some of those pixels are merged with the video or images to produce complex video content. The resulting complex image is then made available for further processing.