Incorrect conversion from HEX to HSL* with this color. about color

[overclokk]

I just created a pull-request with a fix for this issue, it simply normalizes the negative value for the hue.

[freekmurze]

Thanks for the PR! 🙌

[overclokk]

I just found another conversion issue from hsl to hex or rgb but I think it's better to open another issue for that.

[horuskol]

The maths used for HEX/RGB to HSL conversion does sometimes output a negative value for hue, but hsl(354, 70%, 54%) and hsl(-6, 70%, 54%) will produce the same shade of red on display. Because of the cyclic nature of hue, values like 714 and -366 would also be equivalent.

However, the hue could be normalised before being so that it is always between 0 and 360.

while ($hue < 0) {
    // can sometimes be negative
    $hue += 360;
}

while ($hue > 360) {
  // I don't think this is likely, but for balance
  $hue -= 360;
}

edit: I just saw that the markdown preview for hsl(-6, 70%, 54%) didn't work. Interesting. So far I've never had a problem with negative hue whenever I've used it.