说明：  Nehe OpenGL教程，NeHe SDK是把Nehe的教程中所介绍的所有功能，以面向对象的形式，提供给编程人员快速开发的一套编程接口。
(Nehe OpenGL tutorials, NeHe SDK tutorial is to Nehe all the features described in the form of object-oriented, available to programmers to quickly develop a set of programming interfaces.)