Method and apparatus for pixel clipping source and destination windows in a graphics system.

摘要

Methods and apparatus for window clipping source and destination windows in frame buffer graphics systems. The methods and apparatus provided in accordance with the present invention provide economical hardware solutions to moving blocks of pixel data from source areas to destination areas on frame buffers in graphics systems. Methods of moving blocks of pixel data within a frame buffer in a computer graphics frame buffer system comprise the steps of reading a source area from the frame buffer into a memory according to a plurality of source tiles, combining the source tiles with destination tiles in the memory, comparing pixel data identities in the frame buffer with pixel data identities in the memory to determine whether the pixel data identities in the frame buffer match the pixel data identities in the memory, discarding the pixels whose identities in the frame buffer do not match identities in the memory, and updating the frame buffer with the pixel data whose identities in the frame buffer match the pixel identities in the memory. <IMAGE>