Real-time 3D graphics and OpenGL are popular topics, and there are more information and techniques in practice than can ever be published in a single book. You might find the following resources helpful as you further your knowledge and experience.
The OpenGL SuperBible Web Site
The Official OpenGL Web Site
The Khronos Group OpenGL ES Home Page
The SGI OpenGL Extension Registry
SGI's OpenGL Web Site
ATI's Developers Home Page
NVidia's Developers ...