| 摘要 |
<p>A system of display terminals each receiving from an image generator edges which commonly represent a selected two-dimensional projection of three-dimensional objects. Each edge is defined by its intended position on a two-dimensional screen and by attributes for a portion of the screen adjacent the edge. These attributes may include color, brightness, shading and the like. Each display terminal has an edge memory which stores a set of edges ordered by the y-coordinate of their tops and are partially x-ordered. The stored edges are decoded into scanline segments, each segment being the scanline interval between two adjacent edges intersecting that scanline. Each segment is defined by its intended position on the display screen and by its other attributes such as color and brightness. The segments are subsequently decoded into video raster points, each point being defined by its position on the display screen and by attributes such as brightness and color. Since only edges are transmitted from the image generator to the terminals, as opposed to a video raster, a relatively low capacity communication link can be used. Since edges are buffered at each display terminal, rather than video raster data, the edge memories inside the terminals need not be excessively large. The conversion of edges to segments and of segments to video raster is fast and efficient, and allows flickerless display of complex color images.</p> |
