The sRGB gamut expressed in CIE xyY:

	Chromaticity	Red	Green	Blue	White point
	x 		0.6400 	0.3000 	0.1500 	0.3127
	y 		0.3300 	0.6000 	0.0600 	0.3290
	Y 		0.2126 	0.7152 	0.0722 	1.0000

A function is needed that given the values (sans Y) of a
monitor's gamut, converts from sRGB to the monitor's RGB.
An inverse function of this is also needed.