Unity 3D Kudan "Place Markerless Object" whenever mesh leaves screen?

Question

I´m kinda new to Unity 3D and C#. Also i´m not exactly sure how Kudans arbitrary tracking solution works in detail. I´m currently using the Unity Kudan SDK to build a VR positional tracking solution, atleast i will try it. Now my plan is:

1. Whenever the mesh is leaving the screen, i want to freeze it´s position and find new feature points (the "place markerless object" button is doing this: Find new feature point and place a mesh).
2. Once it found new feature points (which should be a matter of milliseconds) it defreezes the position of the mesh and use the new feature points to further alter it´s position.

The "find new feature point" idea is necessary because whenever the mesh and the old feature points are leaving the screen, tracking will get very inaccurate.

I already tried this in SampleApp.cs:

bool VRSignal;

        public void Start()
        {
            //Get Bools from "KudanTracker"
            GameObject g = GameObject.Find("Kudan Camera");
            KudanTracker bScript = g.GetComponent<KudanTracker>();
            bool VRSignal = bScript.ArbiTrackIsTracking();  
        }

     public void Update()
        {
            if(VRSignal == false)
            {
                // from the floor placer.
                Vector3 floorPosition;          // The current position in 3D space of the floor
                Quaternion floorOrientation;    // The current orientation of the floor in 3D space, relative to the device

                _kudanTracker.FloorPlaceGetPose(out floorPosition, out floorOrientation);   // Gets the position and orientation of the floor and assigns the referenced Vector3 and Quaternion those values
                _kudanTracker.ArbiTrackStart(floorPosition, floorOrientation);    // Starts markerless tracking based upon the given floor position and orientations
            }
        }

But now it won´t track properly track anymore, also i´m pretty sure ArbiTrackIsTracking() won´t be the solution for that because it won´t lose tracking when the mesh left the screen.

Do you have any idea to solve this problem?

Answer 1

if I understand well, you want change position of 3d model with trigger as soon as your 3d model disappear of the screen. And you are right, ArbiTrackIsTracking() remain true even if the 3d model go out the screen because if you move again your screen around the 3d model, the 3d model will be always tracked. But if you move too much your smartphone logically the tracking stops.

My idea for your issue is to get the position of your 3d model markerless transform driver, because the 3d model moves in function the position and orientation of your smartphone to track. So you can take the position of the moment where your 3d model begin to be tracked. Then you give a value who will correspond to the difference of first and last position saved. And if this difference is get, you stop the tracking with arbitrack stop.

if you have another question you can ask on my twitter account @ModeLolito I could answer faster. And you can watch my youtube channel to see my works on kudan https://www.youtube.com/user/modelisationLolito