GL_SGIX_slim http://www.opengl.org/registry/specs/SGIX/slim.txt GL_SGIX_slim GL_PACK_MAX_COMPRESSED_SIZE_SGIX 0x831B GL_SLIM8U_SGIX 0x831D GL_SLIM10U_SGIX 0x831E GL_SLIM12S_SGIX 0x831F