提出连续分区裁剪的新思想,按不同的方式多次将平面分成不同的区域,从而简单而快速地舍弃窗外线段,避免没有必要的求交运算。2次分区后提出串联编码技术,将2次编码技术中的两次编码串联起来,继承了第1次编码所做的工作,节省了很多时间;在此基础上,3次分区中提出点对称技术,并将其应用于多次分区,取得了较好的效果。点对称技术所划分平面区域边界的斜率为0°、±45°或无穷大,适合于程序的实现,且与2次编码技术相比,可以舍弃更多的窗外线段,避免更多的求交运算。算法实现清楚地表明该算法能明显提高线段裁剪效率。

Continuous zoning, a novel clipping thought, is put forward in this paper. The plane is divided into many different areas in different way continuously, which can abandon the lines outside the window easily and quickly, and avoid unnecessary computing the point of intersection. After secondary zoning, we implemented the series coding technique to save time and to establish connection between both codes. Then the point symmetry technique which is applied to multiple zoning is carried out in cubic zoning. The slope of the area boundary in cubic zoning is 0~, ~45~ or infinity, which is suitable for the procedure realization. Comparing to secondary coding technique, point symmetry technique can avoid redundant operation of computing the point of intersection. The procedure realization clearly expresses that the algorithm in this paper can improve the line clipping efficiency.