here's a nice solution if you dont have enough money for some real track ir device, you just need a decent webcam.
its quite simple and effective if manage to make it being fine.
just visit: DOWNLOAD PAGE
and download it.
good luck!
here's the way how did I set it up on the Belgrade addon map:
[Externes Medium: https://www.youtube.com/watch?v=4c4i1PmLV28]