/// <summary>
/// Downloads the gameobjects
/// When finished it calls the callback-method
/// </summary>
/// <param name="callback">Method which is called when the download has finished</param>
public void LoadGameObjects(System.Action callback)
{
this.callback = callback;
// only get the first piece of the X3D object
// the first piece contains information if there are successive pieces
restManager.GET(url + "0", OnFinished, null);
}