src/Neuron/GameServer/Map/MapObject.php
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);
	}
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);
	}
The up vector can be manipulated by the movements.