code: public function getUp ($time = NOW)
  	{
  		// Go trough the paths to update
  		foreach ($this->movements as $v)
  		{
  			if ($v->isActive ($time))
  			{
  				$up = $v->getCurrentUp ($time);
  				if (isset ($up))
  				{
  					return $v->getCurrentUp ($time);
  				}
  			}
  		}
  
  		return new Neuron_GameServer_Map_Vector3 (0, 1, 0);
  	}
docs: The up vector can be manipulated by the movements.