Cubehelix to HEX
Convert selected color strings between Cubehelix and HEX color spaces.
For more information about the Cubehelix color space, look for Dave Green's Cubehelix. The specific implementation of Cubehelix for this extension is described below, after the features.
Features
There is a single command "Cubehelix ⇄ HEX" which automatically recognizes selected color format (Cubehelix or HEX) and converts it to the opposite color space. Conversion is done in place. Conversion for multiple selections is supported.
#FFFFFF#ffffff#FFF#fff
The output will be rounded and presented as #FFFFFF.
The extension will recognize any three positive numbers separated by commas and/or spaces. Just remember to add % if you want to specify saturation and/or lightness as percentages. If you want to be more specific, group your coordinates with parentheses, and name the group up to your liking. All drag is valid (except for alphas):
50,120%,60%(355, 0.8, 20%)cubehelix(0, 0%, 5%)hsl(25, 50%, 80%)123 2.,.8
Cubehelix specification doesn't care if the numbers are crazy, so better stick to something close to:
hue : 0-360saturation : 0-1+ / 0-100%+lightness : 0-1 / 0-100%
The output will be rounded and presented as cubehelix(hue, saturation%, lightness%). This makes it easy to replace cubehelix with hsl and preview the color using an appropriate tool.
Cubehelix?
Cubehelix colors, in modern terms, are described by hue : 0-360; saturation : 0-1+ / 0-100%+; and lightness: 0-1 / 0-100%. Although max saturation for some colors can be close to 500%, the real value of this color space lies in colors with saturation up to 100%. As long as you are within this range, colors of any hue keep constant contrast between their lightness values.
For example, a button with the background of (240, 100%, 30%) and the text of (240, 100%, 90%) will measure to the same color accessibility contrast as a button with the background of (160, 50%, 30%) and the text of (160, 100%, 90%).
I typically set saturation 110% for signal (error, warning) colors. The clipping (which leads to contrast mutations) is minimal.
