Some colors get rounded by iro.Color

[nickpearson]

iro.Color seems to round the rgb values in some cases:

new iro.Color("#fff").hexString //=> "#fff"    (ok)
new iro.Color("#eee").hexString //=> "#ededed" (rounded)
new iro.Color("#ddd").hexString //=> "#dedede" (rounded)
new iro.Color("#ccc").hexString //=> "#ccc"    (ok)

You can also see this effect by modifying the CodePen Demo (linked on the intro page) to use #eee as the color option rather than {r: 255, g: 0, b: 0}.

[jaames]

Thanks for letting me know!

I think it might be due to how all iro.Color instances use HSV colors internally, and some rounding when converting RGB -> HSV -> RGB is causing the effect you're seeing. I'll have to investigate further, though

[mbaierl]

Just noticed the same issue... #FF0FF0 -> #FF0FEF and some others...

[jaames]

Finally found the cause; it was a combination of excessive rounding and a strange quirk where converting decimal numbers to hex with .toString(16) would produce unexpected output

I have a working fix in the bug/color-rounding branch if anyone wants to try it

One minor side effect of this fix is that hexString will only provide 6-digit hex output now (e.g new iro.Color("#fff").hexString will be "#ffffff", not "#fff" as before). I can reimplement the shorthand 3-digit output if someone complains, but tbh I feel like keeping it consistent makes more sense anyway

[jaames]

Okay I think I got it, the fix should be in master now. Thanks @nickpearson and @mbaierl :)

[nickpearson]

Works great. Thank you!

I agree that always using the full hex string for consistency is good. If you do happen to decide to convert to the shorthand hex value, here's a simple implementation:

function shortHex(hex) {
  return hex.replace(/^#([0-9a-f])\1([0-9a-f])\2([0-9a-f])\3$/, "#$1$2$3")
}

shortHex("#aabbcc") //=> "#abc"
shortHex("#aabbcd") //=> "#aabbcd"
shortHex("testing") //=> "testing" (returns non-compactible values untouched)
shortHex("#abc")    //=> "#abc"

This implementation of course doesn't do validation and only compacts all-lowercase hex strings, but it's a start.