hsl2rgb · PHP Function to Convert Colors from HSL to RGB

function hsl2rgb ($h, $s, $l) {

    $h /= 60;
    if ($h < 0) $h = 6 - fmod(-$h, 6);
    $h = fmod($h, 6);

    $s = max(0, min(1, $s / 100));
    $l = max(0, min(1, $l / 100));

    $c = (1 - abs((2 * $l) - 1)) * $s;
    $x = $c * (1 - abs(fmod($h, 2) - 1));

    if ($h < 1) {
        $r = $c;
        $g = $x;
        $b = 0;
    } elseif ($h < 2) {
        $r = $x;
        $g = $c;
        $b = 0;
    } elseif ($h < 3) {
        $r = 0;
        $g = $c;
        $b = $x;
    } elseif ($h < 4) {
        $r = 0;
        $g = $x;
        $b = $c;
    } elseif ($h < 5) {
        $r = $x;
        $g = 0;
        $b = $c;
    } else {
        $r = $c;
        $g = 0;
        $b = $x;
    }

    $m = $l - $c / 2;
    $r = round(($r + $m) * 255);
    $g = round(($g + $m) * 255);
    $b = round(($b + $m) * 255);

    return ['r' => $r, 'g' => $g, 'b' => $b];

}