SteamVR tracking for Unity without requiring an HMD to be present or fiddling with the null driver. Useful if you just want to use tracked objects like Vive trackers. This is also not dependent on the SteamVR compositor framerate.

Installation

1. Install OpenVR for Unity XR plugin in your project (the SteamVR Unity plugin is NOT required). Make sure to enable the plugin in the XR management settings or otherwise the openvr_api.dll will not be included in builds.
2. Add this package to the project.

Configuration

Add "requireHmd" : false to the steamvr section of the SteamVR configuration file (<Steam_Installation>/config/steamvr.vrsettings or <AppData>/Local/openvr/config/steamvr.vrsettings).

Usage

1. Attach the OVRT_Manager script to a GameObject.
2. Attach either OVRT_TrackedObject or OVRT_BoundTrackedObject to a GameObject you want to track.
3. Attach OVRT_RenderModel to display the tracked device (e.g. Vive Tracker).

Bindings map the serial number of a tracked device to a string. Any bound tracked object with that string receives poses from the mapped tracked device. Bindings can be assigned by using the Bindings property of OVRT_Manager.

OVRT can also use tracker bindings from SteamVR. See steamvr.vrsettings for the used binding strings. For example, the right shoulder role is called TrackerRole_RightShoulder. When a OVRT_BoundTrackedObject has this binding string set, it receives poses from the tracker that was assigned to the right shoulder in SteamVR.

You can not open the SteamVR tracker role UI when no HMD is connected. In this case you can either edit steamvr.vrsettings or use this tool: SteamVR tracker role utility.

Pose prediction

To predict poses into the future, one can adjust the predictedSecondsToPhotonsFromNow parameter of OVRT_Manager.

Wrong .obj model center fix

The mesh that comes with SteamVR for the Vive Tracker 1.0/3.0 has a wrong center that does not correspond to the origin of the coordinate system from the Vive developer guidelines. OVRT_RenderModel automatically applies a translation of 7.3 and 8 mm respectively. You can turn this off.