/** * Default constructor used only internally. */ public function __construct($p = null) { if ($p instanceof S2Point) { $this->init(S2CellId::fromPoint($p)); } else { if ($p instanceof S2LatLng) { $this->init(S2CellId::fromLatLng($p)); } else { if ($p instanceof S2CellId) { $this->init($p); } } } }