http://dev.gameres.com/Program/Visual/3D/multistream.htm
SetStreamSource函数与数据流的使用
http://www.zxbc.cn/html/20071116/29530_2.html
D3DVERTEXELEMENT9的详细解释
http://blog.youkuaiyun.com/gamerefer/article/details/7825405
顶点着色器入门
http://www.cppblog.com/lovedday/archive/2008/04/06/46357.html