获取vuforia中的跟踪飞机列表

Question

这里是vuforia的初学者。如何获得vuforia中的追踪飞机清单？这是我在vuforia门户网站中获得的代码，用于获取所有可追踪对象的列表，但是如何仅获取被追踪飞机的列表。

        StateManager sm = TrackerManager.Instance.GetStateManager ();

    // Query the StateManager to retrieve the list of
    // currently 'active' trackables 
    //(i.e. the ones currently being tracked by Vuforia)
    IEnumerable<TrackableBehaviour> activeTrackables = sm.GetActiveTrackableBehaviours ();

   // Iterate through the list of active trackables
    Debug.Log ("List of trackables currently active (tracked): ");
    foreach (TrackableBehaviour tb in activeTrackables) {
        Debug.Log("Trackable: " + tb.TrackableName);
    }