HSLa to RGBa js

function hslaConvert(p, q, t)
{
    if (t < 0) t += 1;
    if (t > 1) t -= 1;
    if (t < 1/6) return p + (q - p) * 6 * t;
    if (t < 3/6) return q;
    if (t < 4/6) return p + (q - p) * 6 * (4/6 - t);
    return p
}

function hsla2rgba(h, s, l, a)
{
    // thanks Mohsen! https://stackoverflow.com/a/9493060/460571
    let p, q, r, g, b;

    if (l < 0.5)
    {
        q = l * (1 + s);
    }
    else
    {
        q = l + s - l * s;
    }

    p = 2 * l - q;

    r = Math.floor(hslaConvert(p, q, h + 1/3) * 256);
    g = Math.floor(hslaConvert(p, q, h) * 256);
    b = Math.floor(hslaConvert(p, q, h - 1/3) * 256);

    return [ r, g, b, a ];
}

function hsla2rgba_(h, s, l, a)
{
    let c;

    c = hsla2rgba(h, s, l, a);

    return "rgba(" + c[0] + "," + c[1] + "," + c[2] + "," + c[3] + ")";
}