Drift Correction - Replace the Tracker with MoCap Data

	
/// <summary>
/// Invoked by OVRCameraRig's UpdatedAnchors callback. Allows the Hmd rotation to update the facing direction of the player.
/// </summary>

	public void UpdateTransform(OVRCameraRig rig)
	{
		Transform root = CameraRig.trackingSpace;
		Transform centerEye = CameraRig.centerEyeAnchor;

			Vector3 prevPos = root.position;
			Quaternion prevRot = root.rotation;

                        // Original
			transform.rotation = Quaternion.Euler(0.0f, centerEye.rotation.eulerAngles.y, 0.0f);

			root.position = prevPos;
			root.rotation = prevRot;
		
	}

delta = deltaRotationBetween(root, centerEye)
centerEye.rotation =   Quaternion.Euler(0.0f, centerEye.rotation.eulerAngles.y - delta, 0.0f);

"xflagx" wrote:
It seems that the camera gets updated with some kind of magic behind the scenes.

using UnityEngine;
using System.Collections;

public class TrackingModeChanger : MonoBehaviour {

   void Awake()
   {
      foreach (var rig in GameObject.FindObjectsOfType<OVRCameraRig>())
         rig.UpdatedAnchors += OnUpdatedAnchors;
   }

   void Update ()
   {
      OVRManager.tracker.isEnabled = !Input.GetKey(KeyCode.P);
   }

   void OnUpdatedAnchors(OVRCameraRig rig)
   {
     OVRPose pose = rig.centerEyeAnchor.ToOVRPose(true).Inverse();

     //FIXME: concatenate your desired pose onto "pose".

     rig.trackingSpace.FromOVRPose(pose, true);
   }
}

  private void Rig_UpdatedAnchors(OVRCameraRig obj)
        {
            OVRPose pose = rig.centerEyeAnchor.ToOVRPose(true).Inverse();

            //FIXME: concatenate your desired pose onto "pose".
           
            // The following works
            pose.orientation = Quaternion.Inverse(Quaternion.Euler(1, realWorldUpperBody.rotation.eulerAngles.y, 1) * pose.orientation) * pose.orientation; 
            
            rig.trackingSpace.FromOVRPose(pose, true);
        }

If you don't, there will be a slight wobble due to TimeWarp.

using UnityEngine;
using System.Collections;

public class FakeTracking : MonoBehaviour
{
	public OVRPose centerEyePose = OVRPose.identity;
	public OVRPose leftEyePose = OVRPose.identity;
	public OVRPose rightEyePose = OVRPose.identity;
	public OVRPose leftHandPose = OVRPose.identity;
	public OVRPose rightHandPose = OVRPose.identity;
	public OVRPose trackerPose = OVRPose.identity;

	void Awake()
	{
		OVRCameraRig rig = GameObject.FindObjectOfType<OVRCameraRig>();

		if (rig != null)
			rig.UpdatedAnchors += OnUpdatedAnchors;
	}

	void OnUpdatedAnchors(OVRCameraRig rig)
	{
		if (!enabled)
			return;

		//This doesn't work because VR camera poses are read-only.
		//rig.centerEyeAnchor.FromOVRPose(OVRPose.identity);

		//Instead, invert out the current pose and multiply in the desired pose.
		OVRPose pose = rig.centerEyeAnchor.ToOVRPose(true).Inverse();
		pose = centerEyePose * pose;
		rig.trackingSpace.FromOVRPose(pose, true);

		//OVRPose referenceFrame = pose.Inverse();

		//The rest of the nodes are updated by OVRCameraRig, not Unity, so they're easy.
		rig.leftEyeAnchor.FromOVRPose(leftEyePose);
		rig.rightEyeAnchor.FromOVRPose(rightEyePose);
		rig.leftHandAnchor.FromOVRPose(leftHandPose);
		rig.rightHandAnchor.FromOVRPose(rightHandPose);
		rig.trackerAnchor.FromOVRPose(trackerPose);
	}
}

using UnityEngine;
using System.Collections;

public class FakeTracking : MonoBehaviour
{
    public OVRPose centerEyePose = OVRPose.identity;
    public OVRPose leftEyePose = OVRPose.identity;
    public OVRPose rightEyePose = OVRPose.identity;
    public OVRPose leftHandPose = OVRPose.identity;
    public OVRPose rightHandPose = OVRPose.identity;
    public OVRPose trackerPose = OVRPose.identity;

    void Awake()
    {
        OVRCameraRig rig = GameObject.FindObjectOfType<OVRCameraRig>();

        if (rig != null)
            rig.UpdatedAnchors += OnUpdatedAnchors;
        // print("in awake");
    }

    void OnUpdatedAnchors(OVRCameraRig rig)
    {
        if (!enabled)
            return;

        //This doesn't work because VR camera poses are read-only.
        //rig.centerEyeAnchor.FromOVRPose(OVRPose.identity);

        //Instead, invert out the current pose and multiply in the desired pose.
        OVRPose pose = rig.centerEyeAnchor.ToOVRPose(true).Inverse();
        OVRPose correctedCenterEyePose;

        correctedCenterEyePose.position = rig.centerEyeAnchor.ToOVRPose(true).position;
        correctedCenterEyePose.orientation = rig.centerEyeAnchor.ToOVRPose(true).orientation;
        correctedCenterEyePose.orientation *= Quaternion.Euler(-38.25f, 0.0f, 0.0f);
        // pose = centerEyePose * pose;
        pose = correctedCenterEyePose * pose;
        rig.trackingSpace.FromOVRPose(pose, true);

        //OVRPose referenceFrame = pose.Inverse();

        //The rest of the nodes are updated by OVRCameraRig, not Unity, so they're easy.
        rig.leftEyeAnchor.FromOVRPose(leftEyePose);
        rig.rightEyeAnchor.FromOVRPose(rightEyePose);
        rig.leftHandAnchor.FromOVRPose(leftHandPose);
        rig.rightHandAnchor.FromOVRPose(rightHandPose);
        rig.trackerAnchor.FromOVRPose(trackerPose);
    }
}