| 摘要 |
Disclosed are methods, apparatus ( 1 ) and computer readable media for rendering at least one graphic object ( 80, 90 ) described by at least one edge ( 82 - 86, 92 - 98 ) into a raster pixel image ( 78 ) having a plurality of scan lines and a plurality of pixel locations on each scan line. For each scan line, coordinates of intersection of those edges of the objects that intersect the scan line are determined in a predetermined order. This is preferably achieved by processing edge records ( 418 ) using a number of buffers ( 402, 404,406, 412,420, 422 ) thereby enabling efficient sorting of edge intersections into order. For each adjacent pair of edge intersections, information ( 530 ) associated with the corresponding object is examined to determining a set of active objects ( 508, 510 ) for a span of pixel locations between the corresponding pair of edge intersections. For each span of pixel locations, the corresponding set of active objects is used to determine ( 600 ) a value for each of the locations within the span. The information may include one or more of a fill count, a clip count and other factors. A compositing model accommodating opacity is also disclosed, as are stack operations used to facilitate rendering and other features which contribute to fast processing of image components. |
