练习使用GDI函数绘出基本几何元素，如点、线、矩形、圆、椭圆、多边形、圆弧等、并能够用颜色填充；练习使用GDI函数显示图像；-Practice using GDI functions to draw basic geometry elements such as points, lines, rectangles, circles, ellipses, polygons, arcs, etc., and can be filled with colors practice using GDI