用交点属性值法处理多边形符号轮廓的裁剪

近年来一种处理隐藏线的方法，即在用计算机进行图形隐藏线处理时，为方便起见给所求的交点按其所处理位置赋从不同的属性值标志（我们称它交点属性值法）。在绘图输出时只考虑交点属性累加值及其所在位置从而决定是否输出的方法。该方法的优点是计算方法简单，因而能提高绘图速度。但该方法多用在符号或多边形内填晕线上。本文着重讨论将该方法运用在任意多边形轮廓线的裁前上。经过作者多次试验，其结果是成功的。

OUTLINE-CLIPPING ABOUT OVERLAYING SYMBOLS WITH HELP OF ATTRIBUTES OF INTERSECTION

In late years,a method for hidden line processing appears,which is when computer searches for the hidden line of graph,the attributes of intersection points is given,and when rendering the graph,a intersection point is decided whether to output or not according to its sum of attributive value.The advantage of this method is simplicity in calculation,thus the rendering is speed up.However the method is only used in filling or shading of symbols or polygons.This paper discusses mainly the usage of this method in clipping.The method has been tested many times and may not cause disintegrate of current polygon.The result is satisfactory.