OpenXR Update XrPose and XrInputSource emulated_position Each Frame

Right now emulated_position not updated by OpenXR. Send back space
tracking info back from xrLocateSpace using emulated_position.

Bug: 969131
Change-Id: I41bda233a9354f5885d2fb6c3af6ad087c4f68e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1910559
Commit-Queue: Zheng Qin <zheqi@microsoft.com>
Reviewed-by: Alexander Cooper <alcooper@chromium.org>
Cr-Commit-Position: refs/heads/master@{#717757}

device/vr/openxr/openxr_api_wrapper.cc

@@ -507,7 +507,8 @@ XrTime OpenXrApiWrapper::GetPredictedDisplayTime() const {
 
 XrResult OpenXrApiWrapper::GetHeadPose(
     base::Optional<gfx::Quaternion>* orientation,
-    base::Optional<gfx::Point3F>* position) const {
+    base::Optional<gfx::Point3F>* position,
+    bool* emulated_position) const {
   DCHECK(HasSpace(XR_REFERENCE_SPACE_TYPE_LOCAL));
   DCHECK(HasSpace(XR_REFERENCE_SPACE_TYPE_VIEW));
 
@@ -518,7 +519,15 @@ XrResult OpenXrApiWrapper::GetHeadPose(
                                     frame_state_.predictedDisplayTime,
                                     &view_from_local));
 
-  if (view_from_local.locationFlags & XR_SPACE_LOCATION_ORIENTATION_VALID_BIT) {
+  // emulated_position indicates when there is a fallback from a fully-tracked
+  // (i.e. 6DOF) type case to some form of orientation-only type tracking
+  // (i.e. 3DOF/IMU type sensors)
+  // Thus we have to make sure orientation is tracked.
+  // Valid Bit only indicates it's either tracked or emulated, we have to check
+  // for XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT to make sure orientation is
+  // tracked.
+  if (view_from_local.locationFlags &
+      XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT) {
     *orientation = gfx::Quaternion(
         view_from_local.pose.orientation.x, view_from_local.pose.orientation.y,
         view_from_local.pose.orientation.z, view_from_local.pose.orientation.w);
@@ -534,6 +543,11 @@ XrResult OpenXrApiWrapper::GetHeadPose(
     *position = base::nullopt;
   }
 
+  *emulated_position = true;
+  if (view_from_local.locationFlags & XR_SPACE_LOCATION_POSITION_TRACKED_BIT) {
+    *emulated_position = false;
+  }
+
   return xr_result;
 }
 

device/vr/openxr/openxr_api_wrapper.h

@@ -50,7 +50,8 @@ class OpenXrApiWrapper {
   XrResult EndFrame();
 
   XrResult GetHeadPose(base::Optional<gfx::Quaternion>* orientation,
-                       base::Optional<gfx::Point3F>* position) const;
+                       base::Optional<gfx::Point3F>* position,
+                       bool* emulated_position) const;
   void GetHeadFromEyes(XrView* left, XrView* right) const;
 
   gfx::Size GetViewSize() const;

device/vr/openxr/openxr_controller.cc

@@ -299,25 +299,35 @@ XrResult OpenXrController::UpdateInteractionProfile() {
 
 base::Optional<gfx::Transform> OpenXrController::GetMojoFromGripTransform(
     XrTime predicted_display_time,
-    XrSpace local_space) const {
+    XrSpace local_space,
+    bool* emulated_position) const {
   return GetTransformFromSpaces(predicted_display_time, grip_pose_space_,
-                                local_space);
+                                local_space, emulated_position);
 }
 
 base::Optional<gfx::Transform> OpenXrController::GetPointerFromGripTransform(
     XrTime predicted_display_time) const {
+  bool emulated_position;
   return GetTransformFromSpaces(predicted_display_time, pointer_pose_space_,
-                                grip_pose_space_);
+                                grip_pose_space_, &emulated_position);
 }
 
 base::Optional<gfx::Transform> OpenXrController::GetTransformFromSpaces(
     XrTime predicted_display_time,
     XrSpace target,
-    XrSpace origin) const {
+    XrSpace origin,
+    bool* emulated_position) const {
   XrSpaceLocation location = {XR_TYPE_SPACE_LOCATION};
+  // emulated_position indicates when there is a fallback from a fully-tracked
+  // (i.e. 6DOF) type case to some form of orientation-only type tracking
+  // (i.e. 3DOF/IMU type sensors)
+  // Thus we have to make sure orientation is tracked.
+  // Valid Bit only indicates it's either tracked or emulated, we have to check
+  // for XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT to make sure orientation is
+  // tracked.
   if (FAILED(
           xrLocateSpace(target, origin, predicted_display_time, &location)) ||
-      !(location.locationFlags & XR_SPACE_LOCATION_ORIENTATION_VALID_BIT) ||
+      !(location.locationFlags & XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT) ||
       !(location.locationFlags & XR_SPACE_LOCATION_POSITION_VALID_BIT)) {
     return base::nullopt;
   }
@@ -332,6 +342,11 @@ base::Optional<gfx::Transform> OpenXrController::GetTransformFromSpaces(
   decomp.translate[1] = location.pose.position.y;
   decomp.translate[2] = location.pose.position.z;
 
+  *emulated_position = true;
+  if (location.locationFlags & XR_SPACE_LOCATION_POSITION_TRACKED_BIT) {
+    *emulated_position = false;
+  }
+
   return gfx::ComposeTransform(decomp);
 }
 

device/vr/openxr/openxr_controller.h

@@ -62,7 +62,8 @@ class OpenXrController {
 
   base::Optional<gfx::Transform> GetMojoFromGripTransform(
       XrTime predicted_display_time,
-      XrSpace local_space) const;
+      XrSpace local_space,
+      bool* emulated_position) const;
 
   XrResult UpdateInteractionProfile();
 
@@ -102,7 +103,8 @@ class OpenXrController {
   base::Optional<gfx::Transform> GetTransformFromSpaces(
       XrTime predicted_display_time,
       XrSpace target,
-      XrSpace origin) const;
+      XrSpace origin,
+      bool* emulated_position) const;
 
   std::vector<std::string> GetProfiles() const;
 

device/vr/openxr/openxr_input_helper.cc

@@ -126,8 +126,7 @@ std::vector<mojom::XRInputSourceStatePtr> OpenXRInputHelper::GetInputState(
     }
 
     state->mojo_from_input = controller->GetMojoFromGripTransform(
-        predicted_display_time, local_space_);
-    state->emulated_position = false;
+        predicted_display_time, local_space_, &state->emulated_position);
     state->primary_input_pressed = trigger_button.value().pressed;
     state->primary_input_clicked =
         controller_states_[i].primary_button_pressed &&

device/vr/openxr/openxr_render_loop.cc

@@ -43,8 +43,8 @@ mojom::XRFrameDataPtr OpenXrRenderLoop::GetNextFrameData() {
 
   base::Optional<gfx::Quaternion> orientation;
   base::Optional<gfx::Point3F> position;
-  if (XR_SUCCEEDED(openxr_->GetHeadPose(&orientation, &position))) {
-
+  if (XR_SUCCEEDED(openxr_->GetHeadPose(
+          &orientation, &position, &frame_data->pose->emulated_position))) {
     if (orientation.has_value())
       frame_data->pose->orientation = orientation;
 

device/vr/openxr/test/fake_openxr_impl_api.cc

@@ -629,7 +629,9 @@ XrResult xrLocateSpace(XrSpace space,
   g_test_helper.LocateSpace(space, &(location->pose));
 
   location->locationFlags = XR_SPACE_LOCATION_ORIENTATION_VALID_BIT |
-                            XR_SPACE_LOCATION_POSITION_VALID_BIT;
+                            XR_SPACE_LOCATION_POSITION_VALID_BIT |
+                            XR_SPACE_LOCATION_ORIENTATION_TRACKED_BIT |
+                            XR_SPACE_LOCATION_POSITION_TRACKED_BIT;
 
   return XR_SUCCESS;
 }