ArchPortal Tracker — Support

ArchPortal Tracker streams ARKit camera position and rotation from an iPhone or iPad to Unreal Engine over UDP, as a LONET 2 Live Link subject. It is free, has no account, and collects no data.

Built by Archportals, a virtual production studio in downtown St. Louis.

Requirements

  • An iPhone or iPad that supports ARKit
  • Unreal Engine with the LONET 2 plugin installed
  • Both devices on the same local network, or connected directly via a USB Ethernet adapter

What it sends

Transform data only — position and rotation. The packet also carries focal length, focus distance, aperture and frame rate fields, but these are inert. Set those on the CineCameraActor in Unreal.

The subject registers as ArchPortal_Rig on UDP port 60608.

Finding your workstation's IP address

Open Command Prompt on the workstation and run:

ipconfig

Find the adapter you are actually using and read its IPv4 address. If you are connected through a USB Ethernet adapter, that is the one you want — not Wi-Fi, and not any other adapter listed.

On a direct wired connection with no router involved, the address will usually begin with 169.254. That is normal. It is self-assigned rather than issued by a router, and it can change if the adapter is moved to a different port or machine, so it is worth re-checking with ipconfig if a setup that previously worked stops working.

Setting up Unreal

  1. Open the Live Link panel and add a LONET 2 source.
  2. The field is labelled "Port Number" but expects the full address — IP:PORT, for example 192.168.1.50:60608. Entering only the port number will fail to bind, and the source will appear configured while receiving nothing.
  3. Add a Live Link Controller component to your CineCameraActor and point it at ArchPortal_Rig.
  4. If you are using nDisplay, close the editor completely before launching. The editor holds port 60608 and the two will conflict.

Setting up the device

  1. Enter your workstation's IP address and tap SET.
  2. Mount the device right-side horizontal. The mount orientation is built into the transform math and cannot be changed in the app.
  3. Frame your subject in the reticle, then tap RESET ORIGIN to set world zero.

Using a wired Ethernet adapter

Turning Wi-Fi off is not sufficient. Cellular can still win the route, in which case packets leave the device over cellular and never reach the workstation — while the app reports a healthy socket.

Turn on Airplane Mode, then fully quit and reopen the app before tapping SET. The connection resolves its route once, when it is established, so toggling Airplane Mode without relaunching will not change anything.

Live Link is not picking up the subject

Restart Unreal. This is the fix in almost every case. Live Link sources do not always rebind cleanly — particularly after an IP change, after the editor has been open a while, or after nDisplay has been launched and closed. A full restart of the editor clears it.

If a restart does not resolve it, work through these in order:

  1. Confirm the workstation's IP with ipconfig. If the adapter has been moved, or the machine has rebooted, the address may have changed.
  2. Confirm the app on the device is pointed at that exact address, and tap SET.
  3. Confirm the LONET 2 source has the full IP:PORT, not just the port number. Delete the source and re-add it rather than editing it in place.
  4. If you are running nDisplay, confirm the editor is fully closed. Both will try to hold port 60608.
  5. If you are on a wired adapter, confirm Airplane Mode is on and the app has been quit and relaunched since.

Reading the socket status

  • TX — the socket is bound and packets are leaving the device. This does not confirm that Unreal is receiving them. UDP has no handshake, so the app cannot know whether anything arrived. A green TX with nothing in Unreal is normal when the receiving end is not set up correctly.
  • PREPARING / WAITING — no route to the host yet. Check the address, and see the wired adapter section above.
  • FAILED — socket error. The code shown is the underlying POSIX or DNS error.

Common issues

Tracking drifts over a long take. ARKit accumulates drift, particularly in low-texture environments or under changing light. Tap RESET ORIGIN between setups rather than relying on a single origin across a whole day.

Tracking behaves oddly or stops updating. Quit and reopen the app. If that does not clear it, restart the device. ARKit occasionally needs a clean session.

The camera moves in the wrong axis. Confirm the device is mounted right-side horizontal. Other orientations will produce a valid but incorrectly remapped transform.

Help with setup

If you would rather not debug this yourself, we do paid setup sessions — remote or on site. That includes Live Link configuration, nDisplay and inner frustum setup, network troubleshooting, and getting a tracked camera working end to end.

Email kent@archportals.com or call (314) 246-0026.

Privacy

ArchPortal Tracker collects nothing. There is no account, no analytics, and no network traffic other than the tracking data you send to an address you enter yourself. Camera access is used only for ARKit tracking; no image data leaves the device or is stored. Full privacy policy.