| 摘要 |
A clipping processor clips a two-dimensional subject figure against a clip region by first scan-converting the clip region and storing it as endpoint data of clip segments, then scan-converting the subject figure, clipping the subject segments a scan line at a time against each of the clip segments on that scan line, and converting the clipped segments to pixel data. The clipping process is thus efficiently combined with the standard processes of scan conversion and pixel generation, producing clipped data that are ready for raster output. The clipping process is moreover performable by simple, rapid DDA algorithms, even when the clip region is bounded by high-order curves such as Bezier curves and spline curves, and can easily be implemented in high-speed, dedicated hardware. |
