Unity has me confused on how you want the VR system to work - but I think it’s mostly a documentation and examples issue, rather than fundamental problems. I’m using 2020.1.6f1 at this moment while writing this. The instructions Unity - Manual: Getting started with VR development in Unity imply that we need to separately download the plugins for Oculus, OpenVR, etc - I’d hope that the XR plugin would either download the most common ones for us, or would tell us within Unity that we should download them. XR Plug-in Management is in Project Settings; use the checkboxes in that menu to trigger the downloads for those individual plugins and manage any version issues. And the “OpenVR Loader” label is confusing - is that for OpenVR overall, or is the loader only one specific component and thus I need to add more?
Next, in probably the most critical step in the documentation (Unity - Manual: Configuring your Unity Project for XR), “From Unity’s main menu, go to GameObject > XR > Add XR Rig” - that option doesn’t exist. There is a “Convert main camera to XR Rig” option, but no “Add XR Rig” option. I’m using the HDRP pipeline, and I’ve tried this with both the default sample scene and a brand new one, and there is no “Add XR Rig” option, just the convert option.
This creates the problem that the camera conversion doesn’t add any additional trackers like hand controllers or tracking pucks. Maybe the “Add XR Rig” functionality would create a prefab that includes those trackers, maybe not, I can’t tell. And I don’t see any such prefab anywhere in the project files. So, in order to add the hand trackers, I had to take guesses - it seems that adding extra TrackedPoseDrivers may be the correct option. It would be great if there was a way to get the button input from these controllers (that documentation seems to be under Legacy Input Helpers, and “Legacy” generally means it’s not the current suggested method, so I have no ideas on that one), or to have prefabs with models for the most common controllers. A real, proper sample scene, or implementation of that “Add XR Rig” option and clearer documentation, would go a long way.
By the way, the functionality in the “Convert main camera to XR Rig” tool should update the Clipping Plane of the camera. The default minimum of 0.3 meters is far too high; it will hide your own hand controller from you. It should be set to 0.05 meters or less, preferably less. Further, the documentation references Preview packages, but it seems that the process to show those has disappeared - someone changed the workflow to display preview packages, and the control is now a checkbox in Project Settings → Package Manager. In my opinion, the workflow described in the documentation is superior.
I hope this isn’t too much of a rant, but these are issues that I encountered over the last two days when trying to set up a new VR project. I got the basics working, but it is a puzzle with jumbled pieces.