利用VC编写的CAD小程序 实现直线、圆、椭圆，矩形的绘制，利用透明画刷来实现的。实现了线宽和颜色选择功能-CAD using a small program written in VC To achieve a straight line, circle, ellipse, rectangle drawing, the use of transparent brush to achieve. Achieve a line width and color selection funct