在GDI绘图中，关于窗口和视口的相互关系和操作总会令很多人迷茫，本程序做了一个实例，读源码可以认真体会如果操作窗口和视口。搞懂了两者的关系就可以做view的缩放等操作了-In GDI drawing, the relationship between the Federation and the operating window and viewport on a lot of people confused, this program made ​ ​ an example