GL_SGIX_texture_range
http://www.opengl.org/registry/specs/SGIX/texture_range.txt
	GL_RGB_SIGNED_SGIX 0x85E0
	GL_RGBA_SIGNED_SGIX 0x85E1
	GL_ALPHA_SIGNED_SGIX 0x85E2
	GL_LUMINANCE_SIGNED_SGIX 0x85E3
	GL_INTENSITY_SIGNED_SGIX 0x85E4
	GL_LUMINANCE_ALPHA_SIGNED_SGIX 0x85E5
	GL_RGB16_SIGNED_SGIX 0x85E6
	GL_RGBA16_SIGNED_SGIX 0x85E7
	GL_ALPHA16_SIGNED_SGIX 0x85E8
	GL_LUMINANCE16_SIGNED_SGIX 0x85E9
	GL_INTENSITY16_SIGNED_SGIX 0x85EA
	GL_LUMINANCE16_ALPHA16_SIGNED_SGIX 0x85EB
	GL_RGB_EXTENDED_RANGE_SGIX 0x85EC
	GL_RGBA_EXTENDED_RANGE_SGIX 0x85ED
	GL_ALPHA_EXTENDED_RANGE_SGIX 0x85EE
	GL_LUMINANCE_EXTENDED_RANGE_SGIX 0x85EF
	GL_INTENSITY_EXTENDED_RANGE_SGIX 0x85F0
	GL_LUMINANCE_ALPHA_EXTENDED_RANGE_SGIX 0x85F1
	GL_RGB16_EXTENDED_RANGE_SGIX 0x85F2
	GL_RGBA16_EXTENDED_RANGE_SGIX 0x85F3
	GL_ALPHA16_EXTENDED_RANGE_SGIX 0x85F4
	GL_LUMINANCE16_EXTENDED_RANGE_SGIX 0x85F5
	GL_INTENSITY16_EXTENDED_RANGE_SGIX 0x85F6
	GL_LUMINANCE16_ALPHA16_EXTENDED_RANGE_SGIX 0x85F7
	GL_MIN_LUMINANCE_SGIS 0x85F8
	GL_MAX_LUMINANCE_SGIS 0x85F9
	GL_MIN_INTENSITY_SGIS 0x85FA
	GL_MAX_INTENSITY_SGIS 0x85FB
