MFC绘制不规则窗口,载入一张位图，然后根据想要的图形，去掉多余的颜色，保留想要的颜色，用选出的颜色区域将窗口绘成不规则窗口-MFC drawing irregular window, loading a bitmap, and then you want graphics, get rid of the excess color, to retain the desired color, the color with the sele