Update chroma.js

[devgru]

Newer versions of chroma.js changes HCL representation (called LCH somewhy), same as in D3.js.
Updating the library will make colors with C=0 true grayscale instead of yellowish.

Any version of chroma.js >=0.4.8 will do.
Check the commit with mentioned changes at chroma.js repo: gka/chroma.js@42dd32a

[jacomyma]

Yes that will fix a number of current issues! I'm in the process of updating the tool, but the change is bigger than I expected and impacts many aspects.

The biggest issue is that previous Chroma returned NaN when the conversion from Lab to RGB was impossible (out of bound coordinates). Now it always returns a color, which is a feature but prevents me from detecting when the coordinates are out of bound. Once this is fixed, I'll ship it!

[devgru]

For color validation I recommend using D3 v4 module called d3-color.

Mike Bostock created displayable() function so you just check it like

d3_color.rgb({r, g, b}).displayable()
d3_color.lab({l, a, b}).displayable()

See d3/d3-color#10 (comment)

[jacomyma]

Thanks for this advice :) !

[jacomyma]

I updated Chroma. I did not implement your suggestion and sticked to a tweak copied from Chroma source code. I think the next step would be to package the library into a d3 compatible module not requiring Chroma, but that's for another time! Thanks for your suggestions anyway.

[devgru]

You're welcome!

BTW looks like colors at http://tools.medialab.sciences-po.fr/iwanthue/ are still yellowish with C=0.

[jacomyma]

The repo is up to date but not yet the online website. In a few days.