| 摘要 |
<p>A bitmapped graphics workstation comprising a host computer (502), window managing circuitry (500), a display memory (504), visual display device (506), and multiplexing circuitry (510, 520, 522) connecting the display memory to the display device. The window managing circuitry allows the display memory to be partitioned into plural individually contiguous bitmaps, each corresponding to a different displayed window. The window managing circuitry (500) is divided into a common control section (600) and individual window sections (602-N) corresponding to each window that may be defined. The host computer (502) writes data describing the parameters of each defined window into the individual window managing circuits. It also stores data to be displayed in the windows (including hidden data) in appropriate addresses of each of the bitmaps. As the display device (506) is refreshed, the common and the window circuits of the manager cooperate to select window ''winners'', i.e., the foremost window at each pixel of the screen. The appropriate contents of the bitmap corresponding to the winner at any given time is read under control of the winning window circuit sent to the display device (506) via the multiplexing circuitry.</p> |
