The pure color, hue, can be calculated by giving it a
number between 0 to 255 where pure red has a hue of 0.
H= 0 H= 213H= 170H= 127H= 85
If you change just the hue value, the new hue will have the
same saturation and luminosity values as the original color.
(as used in the HSL model used in PowerPoint)