本算法通过一个小型CAD系统的完整开发过程，循序渐进的讲解了图形系统的设计方法。实例系统实现了三种图形，即直线、矩形即椭圆的绘制、复制、移动、热点等基本功能，值得推荐！-The algorithm through a small CAD system of the complete development process, progressive explained graphics system design method. Examples of three graphics system,