The best thing that came out of the last generation of consoles wasn't actually a video game, it was Kinect. Microsoft shipped millions of units of this weird sensor, and then hardly anybody made games for it. But hackers and roboticists turned Kinect into a whole giant leap for machine vision.
Now it's time for another hacker-led breakthrough, and this time it's all about precision. The HTC Vive does positional tracking with two IR-blasting "Lighthouse" boxes, and an assortment of photodiodes on the VR headset and controllers. Based on the timing of the IR hits, and the information the Lighthouses encode in their blasts, you can get ultra-precise positional coordinates in 3D space (x, y, and z) of the photodiode in question.
Trammell Hudson is leading the charge in making this a technology available to tinkerers, and already has a working prototype based on an Arduino and a ESP8266 microcontroller. So far he can track a single sensor at a range of about a meter. He's working on a software library that should make this easier for anyone else who wants to try.
Maybe the need these days for object tracking isn’t as dire as it was back in 2010. Maybe I’m overselling the importance of this little hack. But as anyone who’s played with Vive knows, there’s something special about its fine-grained, ultra-responsive positional tracking, and I’m ready to see what it could be used for outside of VR.