function toRGB($H, $S, $L) {
        $H = $H % 360;
        if ($H < 0) $H += 360;

        $S = min(100, max(0, $S));
        $L = min(100, max(0, $L));

        $H = $H / 360;
        $S = $S / 100;
        $L = $L / 100;

        if ($S == 0) {
            $r = $g = $b = $L;
        } else {
            $temp2 = $L < 0.5 ?
                $L*(1.0 + $S) :
                $L + $S - $L * $S;

            $temp1 = 2.0 * $L - $temp2;

            $r = $this->toRGB_helper($H + 1/3, $temp1, $temp2);
            $g = $this->toRGB_helper($H, $temp1, $temp2);
            $b = $this->toRGB_helper($H - 1/3, $temp1, $temp2);
        }

        $out = array('color', $r*255, $g*255, $b*255);
        return $out;
    }