Normally when I want to create a class constructor that accepts different types of parameters, I'll use a kludgy overloading principle of not defining any args in the constructor definition: e.g. for an ECEF coordinate class constructor, I want it to accept either $x, $y and $z arguments, or to accept a single array argument containg x, y and z values, or to accept a single LatLong object I'd create a constructor looking something like:

function __construct()
    {
        //  Identify if any arguments have been passed to the constructor
        if (func_num_args() > 0) {
            $args = func_get_args();
            //  Identify the overload constructor required, based on the datatype of the first argument
            $argType = gettype($args[0]);
            switch($argType) {
                case 'array' :
                     //  Array of Cartesian co-ordinate values
                     $overloadConstructor = 'setCoordinatesFromArray';
                     break;
                case 'object' :
                     //  A LatLong object that needs converting to Cartesian co-ordinate values
                     $overloadConstructor = 'setCoordinatesFromLatLong';
                     break;
                default :
                     //  Individual Cartesian co-ordinate values
                     $overloadConstructor = 'setCoordinatesFromXYZ';
                     break;
            }
            //  Call the appropriate overload constructor
            call_user_func_array(array($this,$overloadConstructor),$args);
        }
    }   //  function __construct()

I'm looking at an alternative: to provide a straight constructor with $x, $y and $z as defined arguments, and to provide static methods of createECEFfromArray() and createECEFfromLatLong() that handle all the necessary extraction of x, y and z; then create a new ECEF object using the standard constructor, and return that

Which option is cleaner from an OO purists perspective?