GL_SGI_color_matrix
http://www.opengl.org/registry/specs/SGI/color_matrix.txt
	GL_COLOR_MATRIX_SGI 0x80B1
	GL_COLOR_MATRIX_STACK_DEPTH_SGI 0x80B2
	GL_MAX_COLOR_MATRIX_STACK_DEPTH_SGI 0x80B3
	GL_POST_COLOR_MATRIX_RED_SCALE_SGI 0x80B4
	GL_POST_COLOR_MATRIX_GREEN_SCALE_SGI 0x80B5
	GL_POST_COLOR_MATRIX_BLUE_SCALE_SGI 0x80B6
	GL_POST_COLOR_MATRIX_ALPHA_SCALE_SGI 0x80B7
	GL_POST_COLOR_MATRIX_RED_BIAS_SGI 0x80B8
	GL_POST_COLOR_MATRIX_GREEN_BIAS_SGI 0x80B9
	GL_POST_COLOR_MATRIX_BLUE_BIAS_SGI 0x80BA
	GL_POST_COLOR_MATRIX_ALPHA_BIAS_SGI 0x80BB
