System and method for simultaneously displaying a plurality of video

Abstract

A computer system and graphics controller which stores video data in memory corresponding to a plurality of video objects and presents the video objects on a video monitor, wherein a plurality of the video objects have differing numbers of bits per pixel formats. System memory stores video data in a plurality of memory areas for each of the plurality of video objects, wherein the plurality of video objects may have differing numbers of bits per pixel. The graphics controller obtains portions of the video data from the plurality of memory areas and in response provides video signals to the video monitor. The computer system and graphics controller performs pointer-based and/or display list-based video refresh operations that enable video object data to be assembled on a per window or per object basis, thereby greatly increasing the performance of the graphical display. The graphics controller maintains pointers to various areas or buffers in system memory comprising video or graphics display information. The graphics controller also manipulates respective object information workspace memory areas corresponding to each object or window, wherein the workspace areas specify data types, color depths or bits per pixel, 3D depth values, alpha blending information, screen position, etc. for the respective window or object on the screen. The graphics controller utilizes this information, as well as information received from the software driver regarding screen changes, to assemble a display refresh list in system memory. This information is used during the screen refresh to display the various windows or objects on the screen very quickly and efficiently. Thus only the number of bits per pixel required for each video object is required to be stored in memory.