Scaffold Function: Convert hex to rgba

function Scaffold_hexa2rgba($hex,$alpha=1)
{
    $hex = str_replace('#','',$hex);
    $r = $g = $b = 0;

    switch(strlen($hex)){
        case 3:
            list($r,$g,$b) = str_split($hex);
            $r = hexdec($r.$r);
            $g = hexdec($g.$g);
            $b = hexdec($b.$b);
            return "rgba($r,$g,$b,$alpha)";
            break;

        case 6:
            list($r1,$r2,$g1,$g2,$b1,$b2) = str_split($hex);
            $r = hexdec($r1.$r2);
            $g = hexdec($g1.$g2);
            $b = hexdec($b1.$b2);
            return "rgba($r,$g,$b,$alpha)";
            break;
        default:
            break;
    }
}