GL_SGIX_async_pixel
http://www.opengl.org/registry/specs/SGIX/async_pixel.txt
GL_SGIX_async_pixel
GL_ASYNC_TEX_IMAGE_SGIX 0x835C
GL_ASYNC_DRAW_PIXELS_SGIX 0x835D
GL_ASYNC_READ_PIXELS_SGIX 0x835E
GL_MAX_ASYNC_TEX_IMAGE_SGIX 0x835F
GL_MAX_ASYNC_DRAW_PIXELS_SGIX 0x8360
GL_MAX_ASYNC_READ_PIXELS_SGIX 0x8361