[MRTK3] Adding support for unbounded tracking mode

com.microsoft.mrtk.input/Assets/Prefabs/MRTK XR Rig.prefab

@@ -259,6 +259,7 @@ GameObject:
   m_Component:
   - component: {fileID: 2351505566903569412}
   - component: {fileID: 3712792914886690938}
+  - component: {fileID: 2813607766961918107}
   m_Layer: 0
   m_Name: Camera Offset
   m_TagString: Untagged
@@ -302,6 +303,18 @@ MonoBehaviour:
   m_CameraFloorOffsetObject: {fileID: 2351505566903569413}
   m_RequestedTrackingOriginMode: 0
   m_CameraYOffset: 1.6
+--- !u!114 &2813607766961918107
+MonoBehaviour:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 2351505566903569413}
+  m_Enabled: 1
+  m_EditorHideFlags: 0
+  m_Script: {fileID: 11500000, guid: c4d642881628ba842b14068a50038965, type: 3}
+  m_Name: 
+  m_EditorClassIdentifier: 
 --- !u!1 &2351505567455720334
 GameObject:
   m_ObjectHideFlags: 0

com.microsoft.mrtk.input/Editor/Inspectors/UnboundedTrackingModeInspector.cs

@@ -0,0 +1,43 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using Unity.XR.CoreUtils;
+using UnityEditor;
+using UnityEngine;
+using UnityEngine.XR;
+
+namespace Microsoft.MixedReality.Toolkit.Input.Editor
+{
+    /// <summary>
+    /// A custom inspector for the <see cref="UnboundedTrackingMode"/> component.
+    /// </summary>
+    [CustomEditor(typeof(UnboundedTrackingMode))]
+    internal class UnboundedTrackingModeInspector : UnityEditor.Editor
+    {
+        /// <inheritdoc/>
+        public override void OnInspectorGUI()
+        {
+#if UNITYXR_MANAGEMENT_PRESENT
+            EditorGUILayout.HelpBox("This MRTK component works along side XROrigin to ensure that the XRInputSubsystem " +
+                "has the TrackingOriginModeFlags.Unbounded flag set if this flag is supported.\n\nNote, the " +
+                "TrackingOriginModeFlags.Unbounded flag is only applied if the XROrigin.RequestedTrackingOriginMode is " +
+                "set to \"Not Specified\" and the device supports unbounded spaces.", MessageType.Info);
+
+            if (target is UnboundedTrackingMode unboundedTrackingMode)
+            {
+                XROrigin xrOrigin = unboundedTrackingMode.GetComponent<XROrigin>();
+                if (xrOrigin.RequestedTrackingOriginMode != XROrigin.TrackingOriginMode.NotSpecified)
+                {
+                    EditorGUILayout.HelpBox("The XROrigin's tracking origin mode is not set to \"Not Specified\". This " +
+                        "component will only put the XRInputSubsystem into unbounded mode if XROrigin's tracking mode is set " +
+                        "\"Not Specified\"", MessageType.Warning);
+                }
+            }
+#else
+            EditorGUILayout.HelpBox("This MRTK component is unable to put the XRInputSubsystem into unbounded mode, as the " +
+                "com.unity.xr.management package hasn't been included. Please include com.unity.xr.management version 4.2 " +
+                "for this component to function.", MessageType.Warning);
+#endif
+        }
+    }
+}

com.microsoft.mrtk.input/Editor/MRTK.Input.Editor.asmdef

@@ -4,10 +4,12 @@
     "references": [
         "Microsoft.MixedReality.Toolkit.Core",
         "Microsoft.MixedReality.Toolkit.Core.Editor",
-        "Microsoft.MixedReality.Toolkit.Input",
+        "Microsoft.MixedReality.Toolkit.Input",        
+        "Unity.XR.CoreUtils",
         "Unity.XR.CoreUtils.Editor",
         "Unity.XR.Interaction.Toolkit",
-        "Unity.XR.Interaction.Toolkit.Editor"
+        "Unity.XR.Interaction.Toolkit.Editor",
+        "Unity.XR.Management"
     ],
     "includePlatforms": [
         "Editor"
@@ -28,6 +30,11 @@
             "name": "com.atteneder.ktx",
             "expression": "",
             "define": "KTX_PRESENT"
+        },
+        {
+            "name": "com.unity.xr.management",
+            "expression": "4.2",
+            "define": "UNITYXR_MANAGEMENT_PRESENT"
         }
     ],
     "noEngineReferences": false

com.microsoft.mrtk.input/MRTK.Input.asmdef

@@ -7,6 +7,7 @@
         "Unity.InputSystem",
         "Unity.XR.CoreUtils",
         "Unity.XR.Interaction.Toolkit",
+        "Unity.XR.Management",
         "glTFast",
         "Ktx"
     ],
@@ -37,6 +38,11 @@
             "name": "com.atteneder.ktx",
             "expression": "",
             "define": "KTX_PRESENT"
+        },
+        {
+            "name": "com.unity.xr.management",
+            "expression": "4.2",
+            "define": "UNITYXR_MANAGEMENT_PRESENT"
         }
     ],
     "noEngineReferences": false

com.microsoft.mrtk.input/Tracking/UnboundedTrackingMode.cs

@@ -0,0 +1,178 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using Unity.XR.CoreUtils;
+using UnityEngine;
+using UnityEngine.XR;
+
+#if MROPENXR_PRESENT
+using Microsoft.MixedReality.OpenXR.Remoting;
+#endif
+
+#if UNITYXR_MANAGEMENT_PRESENT
+using UnityEngine.XR.Management;
+#endif
+
+namespace Microsoft.MixedReality.Toolkit.Input
+{
+    /// <summary>
+    /// This component works along side Unity's <see cref="XROrigin"/> to ensure that the <see cref="XRInputSubsystem"/> has
+    /// the <see cref="TrackingOriginModeFlags.Unbounded"/> flag set on its tracking origin mode if this flag is supported.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// Devices like the HoloLens 2 should use unbounded reference space. This reference space enables the viewer to move
+    /// freely through a complex environment, often many meters from where they started, while always optimizing for coordinate
+    /// system stability near the viewer. For more information about unbounded space see the
+    /// <see href="https://registry.khronos.org/OpenXR/specs/1.0/html/xrspec.html#XR_MSFT_unbounded_reference_space">OpenXR Specification</see>.
+    /// </para>
+    /// <para>
+    /// The <see cref="TrackingOriginModeFlags.Unbounded"/> flag is only applied if the <see cref="XROrigin.RequestedTrackingOriginMode"/>
+    /// is set to <see cref="XROrigin.TrackingOriginMode.NotSpecified"/>, the device supports unbounded spaces, and <see cref="XRInputSubsystem"/>
+    /// current tracking mode is set to <see cref="TrackingOriginModeFlags.Device"/>.
+    /// </para> 
+    /// </remarks>
+    [RequireComponent(typeof(XROrigin))]
+    [AddComponentMenu("MRTK/Input/Unbounded Tracking Mode")]
+    public class UnboundedTrackingMode : MonoBehaviour
+    {
+#if UNITYXR_MANAGEMENT_PRESENT
+        private XRInputSubsystem m_inputSubsystem;
+        private XROrigin.TrackingOriginMode m_requestedTrackingOriginMode = XROrigin.TrackingOriginMode.NotSpecified;
+
+        /// <summary>
+        /// A Unity event function that is called when the script component has been enabled.
+        /// </summary>
+        /// <remarks>
+        /// This will attempt to set <see cref="XRInputSubsystem"/> tracking mode to <see cref="TrackingOriginModeFlags.Unbounded"/>.
+        /// </remarks>
+        private void OnEnable()
+        {
+            XRGeneralSettings xrSettings = XRGeneralSettings.Instance;
+            if (xrSettings == null)
+            {
+                Debug.LogWarning($"EyeLevelSceneOrigin: XRGeneralSettings is null.");
+                return;
+            }
+
+            XRManagerSettings xrManager = xrSettings.Manager;
+            if (xrManager == null)
+            {
+                Debug.LogWarning($"EyeLevelSceneOrigin: XRManagerSettings is null.");
+                return;
+            }
+
+            XRLoader xrLoader = xrManager.activeLoader;
+            if (xrLoader == null)
+            {
+                Debug.LogWarning($"EyeLevelSceneOrigin: XRLoader is null.");
+                return;
+            }
+
+            m_inputSubsystem = xrLoader.GetLoadedSubsystem<XRInputSubsystem>();
+            if (m_inputSubsystem == null)
+            {
+                Debug.LogWarning($"EyeLevelSceneOrigin: XRInputSubsystem is null.");
+                return;
+            }
+
+            XROrigin xrOrigin = gameObject.GetComponent<XROrigin>();
+            if (xrOrigin != null)
+            {
+                m_requestedTrackingOriginMode = xrOrigin.RequestedTrackingOriginMode;
+            }
+
+            m_inputSubsystem.trackingOriginUpdated += XrInput_trackingOriginUpdated;
+
+            EnsureUnboundedModeSetIfSupported();
+        }
+
+        /// <summary>
+        /// A Unity event function that is called when the script component has been disabled.
+        /// </summary>
+        private void OnDisable()
+        {
+            if (m_inputSubsystem != null)
+            {
+                m_inputSubsystem.trackingOriginUpdated -= XrInput_trackingOriginUpdated;
+                m_inputSubsystem = null;
+            }
+        }
+
+        private void XrInput_trackingOriginUpdated(XRInputSubsystem obj)
+        {
+            if (isActiveAndEnabled)
+            {
+                EnsureUnboundedModeSetIfSupported();
+            }
+        }
+
+        private void EnsureUnboundedModeSetIfSupported()
+        {
+            TrackingOriginModeFlags currentMode = m_inputSubsystem.GetTrackingOriginMode();
+            TrackingOriginModeFlags desiredMode = GetDesiredTrackingOriginMode(m_inputSubsystem);
+
+            if (m_requestedTrackingOriginMode == XROrigin.TrackingOriginMode.NotSpecified &&
+                (currentMode == TrackingOriginModeFlags.Device || currentMode == TrackingOriginModeFlags.Unbounded) &&
+                currentMode != desiredMode)
+            {
+                Debug.Log($"UnboundedTrackingMode: TrySetTrackingOriginMode to {desiredMode}");
+                if (!m_inputSubsystem.TrySetTrackingOriginMode(desiredMode))
+                {
+                    Debug.LogWarning($"UnboundedTrackingMode: Failed to set tracking origin to {desiredMode}.");
+                }
+                else if (desiredMode == TrackingOriginModeFlags.Unbounded)
+                {
+                    ApplyUnboundedCameraOffset();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Apply the <see cref="XROrigin.CameraYOffset"/> to the transform.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// The <see cref="XROrigin"/> class does not yet support "unbounded" devices, which results in 
+        /// <see cref="XROrigin"/> failing to correctly apply the specified camera height offset for
+        /// "unbounded" device. This function addresses this limitation that is typically seen during
+        /// remoting scenarios.
+        /// </para>
+        /// <para>
+        /// Note, problems with the camera height offset are typically seen when using holographic
+        /// remoting on HoloLens.
+        /// </para>
+        /// </remarks>
+        private void ApplyUnboundedCameraOffset()
+        {
+            if (!Application.isPlaying)
+            {
+                return;
+            }
+
+            XROrigin xrOrigin = gameObject.GetComponent<XROrigin>();
+            if (xrOrigin != null &&
+                xrOrigin.CameraFloorOffsetObject != null)
+            {
+                var offsetTransform = xrOrigin.CameraFloorOffsetObject.transform;
+                var desiredPosition = offsetTransform.localPosition;
+                desiredPosition.y = xrOrigin.CameraYOffset;
+                offsetTransform.localPosition = desiredPosition;
+            }
+        }
+
+        private static TrackingOriginModeFlags GetDesiredTrackingOriginMode(XRInputSubsystem xrInput)
+        {
+            TrackingOriginModeFlags supportedFlags = xrInput.GetSupportedTrackingOriginModes();
+            TrackingOriginModeFlags targetFlag = TrackingOriginModeFlags.Device;   // All OpenXR runtime must support LOCAL space
+
+            if (supportedFlags.HasFlag(TrackingOriginModeFlags.Unbounded))
+            {
+                targetFlag = TrackingOriginModeFlags.Unbounded;
+            }
+
+            return targetFlag;
+        }
+#endif
+    }
+}