多边形以n, x_array, y_array形式给出，其中x_array，y_array中存放着多边形的n个顶点的x, y坐标。扫描线填色算法的基本思想是：



用水平扫描线从上到下扫描由点线段构成的多段构成的多边形。每根扫描线与多边形各边产生一系列交点。将这些交点按照x坐标进行分类，将分类后的交点成对取出，作为两个端点，以所填的色彩画水平直线。多边形被扫描完毕后，填色也就完成。



上述基本思想中，有几个问题需要解决或改善-polygon n, x_array, y_array form given, which x_array, y_array leave a polygon of n vertices x, y coordinates. Scan Line coloring algorithm is the basic idea : Scan line with the level of scanning from top to bottom line point of the multi-form polygon. Each scan-line and polygon edges in the series of intersection. Nodal according to these x coordinates for classification, the classification will be paired Retrieve intersection, as two endpoints filled with color pictures of horizontal lines. Polygon scan was completed, the coloring will be completed. These basic ideas, there are several problems to be solved or improved