GL_SGIX_fragments_instrument
https://www.khronos.org/registry/OpenGL/extensions/SGIX/SGIX_fragments_instrument.txt
GL_SGIX_fragments_instrument

	GL_FRAGMENTS_INSTRUMENT_SGIX 0x8313
	GL_FRAGMENTS_INSTRUMENT_COUNTERS_SGIX 0x8314
	GL_FRAGMENTS_INSTRUMENT_MAX_SGIX 0x8315