class MyFactory implements GeoIO\Factory
{
    public function createPoint($dimension, array $coordinates, $srid = null)
    {
        return MyPoint($coordinates['x'], $coordinates['y']);
    }

    // ...
}

$factory = MyFactory();
$parser = new GeoIO\WKB\Parser\Parser($factory);

$myPoint = $parser->parse('000000000140000000000000004010000000000000'); // POINT(2.0 4.0)