利用MFC，简单的图形界面，简单的算法，实现凸包的绘制-Using MFC, a simple graphical interface, a simple algorithm to achieve the convex hull of the draw

实现凸包算法，可以清晰的看见递归的过程，也可以看出最后的区域-Convex hull algorithm recursive process, you can clearly see, the last area can also be seen