1GL_EXT_Cg_shader 2http://download.nvidia.com/developer/GLSL/GLSL%20Release%20Notes%20for%20Release%2060.pdf 3GL_EXT_Cg_shader 4 GL_CG_VERTEX_SHADER_EXT 0x890E 5 GL_CG_FRAGMENT_SHADER_EXT 0x890F 6