Three-way/n-way contrast

[matatk]

Sometimes there are >2 colours that need to be compared (e.g. enabled/disabled controls -- though these should probably also be indicated with other visual means as well as colour -- and different data series in charts).

I would love to see this being able to work out the ratios between three colours (or more), and also find solutions to the contrast ratios, if they exist.

Example of an n-way tool: http://jxnblk.com/colorable/demos/matrix/ (it also does normal two-colour ones).