符合国家标准的工程图中相交点画线算法

Algorithm of intersecting dash dot lines of engineering drawings in accord with GB

国家标准中,图形中心线的线型是细点画线,两条点画线相交,应是线段交接,为此提出一种算法,该算法为:任意地输入两相交点画线4个端点的坐标,根据设定的原则,计算出点画线的线段长度,绘制2条交接在线段处的点画线。该算法用于计算机绘工程图,使绘制出的工程图符合国家标准[1]。

Based on GB, the central line of drawing is thin dash dot line, and two dash dot line intersection must be in line segments. Give an algorithm： input the coordinates of four end points of two intersecting dash dot lines at random, compute the lengths of line segments of dash dot lines based on a given principle, and draw two dash dot lines intersecting in line segments. This algorithm can be used in computer making engineering drawings in accord with GB.