摘要
用任意排列的边表构成一平面几何图形块的基本数据结构,代替顺序排列的点表及内,外环的图形描述方式。用两图形块相互裁剪的方法,将二维几何构形归结为最基本的线段裁剪。在以图形块为窗口对直线段和圆弧裁剪的过程中,讨论了窗口边(直线段、圆弧)和被裁剪线段的相交条件,有效交点的获取和被裁剪线段端点可见性的快速判断方法。
A random array edge table is described as a basic data structure to form a plane chart, instead of the concepts about inner or outer rounding ring and point table. A newway that two plane geometric charts are clipped together is used to reduce the problem of two dimensional geometric modeling to the most basic problem of clipping segments. While clipping the line and arc segments with the window in a plane geometric graph, we discuss the condition of crossing, the getting of the effective crossing point and a kind of rapid way to judge the visibility about an end point on the clipped segment.
关键词
计算机制图
算法
几何构形
computer cartography
algorithm
data structure
geometric modeling
clipping
