Sets the tracking mode of the XR subsystems. This adds functionality that isn't in the core Unity interface to set XR hardware tracking modes - eg, Oculus devices will track based on initial headset position, wheras OpenVR devices will track based on floor position. This allows you to normalize this across all devices.

SetTrackingMode.cs

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR;

namespace absurdjoy.axe
{
	public class SetTrackingMode : MonoBehaviour
	{
		public TrackingOriginModeFlags trackingFlags = TrackingOriginModeFlags.Floor;
		public bool recenterOnSet = true;

		private void OnEnable()
		{
			SetTrackingModeTo(); // Change tracking mode on whatever is already initialized.
			SubsystemManager.reloadSubsytemsCompleted += SetTrackingModeTo; // Add listener for future inits.
		}

		private void OnDisable()
		{
			SubsystemManager.reloadSubsytemsCompleted -= SetTrackingModeTo;
		}

		/// <summary>
		/// Sets the tracking mode of all currently initialized XR Subsystems to the origin configured in the inspector.
		/// </summary>
		public void SetTrackingModeTo()
		{
			SetTrackingModeTo(trackingFlags, recenterOnSet);
		}
		
		/// <summary>
		/// Sets the tracking mode of all currently initialized XR Subsystems to the origin specified. 
		/// </summary>
		public void SetTrackingModeTo(TrackingOriginModeFlags flags, bool recenter) {
			List<XRInputSubsystem> subsystems = new List<XRInputSubsystem>();
			SubsystemManager.GetInstances(subsystems);

			foreach (var subsystem in subsystems)
			{
				if (subsystem.TrySetTrackingOriginMode(flags))
				{
					if (recenter)
					{
						// Now that we've changed the origin mode we'll have to recalibrate to this new point
						// in space (it will re-zero off of the last-set-height, which for Oculus Quest is the
						// HMD boot position).
						subsystem.TryRecenter();
					}
				}
				else
				{
					Debug.LogError("Failed to set the TrackingOriginMode of id:"+subsystem.SubsystemDescriptor.id, gameObject);
				}
			}
		}
	}
}