Apparatus and method for specifying windows with priority ordered rectangles in a computer video graphics system

摘要

A method and a device for distinguishing which pixels are to be displayed in a set of overlapping, rectangular windows in video graphics display are provided. Windows are specified as a priority ordered list of rectangles or other shapes, so that each window is computed as being visible at those pixels that are inside its rectangle but outside the rectangles of all higher priority windows. The number of rectangles required is equal to the number of rectangular windows, irrespective of the degree of overlap.