Those controllers don’t track themselves. And now, you too can create your own with a free license from Valve Software. (credit: Valve Software)

For now, if you want to play any of the virtual reality games or apps in the SteamVR ecosystem, the only hardware you can use comes from HTC. That may soon change, however. SteamVR creator Valve has opened the floodgates to a new wave of VR peripherals with a surprise Thursday announcement: all licenses for the system’s VR tracking interface will be free.

What does this mean? To be clear, this isn’t an announcement for new headsets, though SteamVR has always been advertised as a platform that will eventually be open to other VR headset manufacturers. Rather, this is all about virtual reality add-ons.

If a hardware maker wants to create physical objects that will interface with SteamVR—like a pair of gloves, a two-handed shotgun, a piece of fake medical equipment, or whatever else you can imagine—the object in question needs to be tracked by the system’s “room-scale” pair of infrared boxes. The HTC Vive’s headset and wands play nicely in VR mostly because they’re each covered by dozens of IR receiver dots. The headset and wands are spread out in such a way that, no matter how you hold or use them, one of the Vive’s two tracking boxes can see enough of the IR dots to translate those physical objects’ positions and rotations in 3D space. That’s why you see them appear smoothly in a virtual play space. (You can read more on how this all works at Valve’s licensing announcement page, which includes peripheral suggestions, such as table-tennis paddles and golf clubs.)