1GL_NV_texgen_emboss 2http://oss.sgi.com/projects/ogl-sample/registry/NV/texgen_emboss.txt 3 GL_EMBOSS_LIGHT_NV 0x855D 4 GL_EMBOSS_CONSTANT_NV 0x855E 5 GL_EMBOSS_MAP_NV 0x855F 6