说明：  本文详细讨论了基于扫描线填充算法对多边形区域进行 图案填充问题。尽管位图可以看作是一个二值图像，但为了方 便起见，在本文中，我们将位图和图像区分开来讨论。
(This article is discussed in detail based on the scan line polygon fill algorithm to fill the problem areas of design. Although bitmaps can be seen as a binary image, but the sake of convenience, in this paper, we will place a distinction between maps and images for discussion.)