Container::distanceCompare

static function distanceCompare(array $p1, array $p2)
{
	$zero = array(0,0,0);
	$d1 = self::calculateDistance($p1, $zero);
	$d2 = self::calculateDistance($p2, $zero);

	if($d1 == $d2)
		return 0;

	return ($d1 < $d2) ? -1 : 1;
}