说明：  利用OpenGL画的一个三维球体(有光照，可以调整球面数，可以调整球体半径，有旋转，有移动等基本操作，充分表现人机交互的效果。比较适合初学者。便于理解OpenGL画图的数学原理.
(use OpenGL 3D painting of a ball (a light, adjust the number of spherical, the radius can be adjusted Ball, a rotating movement, such as basic operation fully demonstrated the effectiveness of human-computer interaction. More suitable for beginners. OpenGL drawing easier to understand the mathematical principles.)