HSL to RGB color conversion

Question

I am looking for a JavaScript / PHP algorithm to convert between HSL color to RGB.

It seems to me that HSL is not very widely used so I am not having much luck search

Answer 1

Here's a fast, super-simple, branchless version in GLSL:

vec3 hsl2rgb( vec3 c ) {
    vec3 rgb = clamp(abs(mod(c.x*6.0 + vec3(0.0, 4.0, 2.0), 6.0)-3.0)-1.0, 0.0, 1.0);
    return c.z + c.y * (rgb-0.5)*(1.0-abs(2.0*c.z-1.0));
}

Doesn't get much shorter than that ~

---

Link to the original proof-of-concept: https://www.shadertoy.com/view/XljGzV

(Disclaimer: not my code!)