说明：  1. 在练习8的基础上，实现Deferred Shading算法； 考察目的： 1. 阅读文献，理解并实现文献中算法； 2. 通过FrameBufferObject实现render-to-texture技术； 3. 实现multiple-render-targets技术；
(Deferred Shading algorithm on the basis of Exercise 8 aim to investigate: 1. Reading literature, understanding and literature algorithm FrameBufferObject achieve the render-to-texture technology 3. Multiple-render-targets technology )