| 摘要 |
<p>57 A graphics display unit providing rapid filling of predetermined areas of the display screen with one or more predefined repetitive patterns stored in the undisplayed portion of a frame buffer memory. The picture processor in executing a display list will encounter commands to load the predefined pattern(s) into the undisplayed portion of the frame buffer memory. The pattern is copied or replicated from there across the entire width of the frame buffer, with the final replication of the pattern being truncated. The display control unit fills the predetermined shapes or areas of the image to be displayed with the pattern(s) thusly loaded into the frame buffer memory, by copying sections of the scan lines of the replicated pattern up into the displayed section of the frame buffer specifically defining the shape to be filled-in. Pattern alignment between contiguous areas to be filled in with that pattern, is provided. Rapid filling is achieved by having the portion of the pattern coincide, scan line by scan line, with the image to be filled, in the X dimension. The replicated pattern becomes visible when the shape is drawn on the screen, with the shape acting as a window for viewing the pattern.</p> |
