| 摘要 |
A method is provided for managing windows in a raster display. The method includes generating a first display map defining sequential picture element runs, each run having a common set of windows containing the picture elements of the run. The windows are arranged in a stacking order and include a topmost window which is drawn in the raster display, the other windows being covered by the topmost window. A window operation occurs when a window is added, deleted or moved, and when the window stacking order is changed. In response to a window operation, there is generating a second display map defining sequential picture element runs, each run having a common set of windows containing the picture elements of the run. The windows are arranged in a stacking order and including a topmost window which is drawn in the raster display, the other windows being covered by the topmost window. In order to refresh the raster display, the first display map is compared with the second display map to identify picture elements whose topmost window has changed. The raster display is repainted by writing the changed picture elements with data from the topmost window of the identified picture elements.
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