VR: Fix WebVR magic window poses with rotated device.

Starting with gvr 1.13, GVR ignores the screen rotation and always
delivers poses as though the phone was in portrait orientation.
This CL applies the proper rotation to gvr-provided poses to account
for the screen rotation.

Bug: 817889
Change-Id: Ie705046439775b2a34d30b177db6191414acaa10
Reviewed-on: https://chromium-review.googlesource.com/944006
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: Bill Orr <billorr@chromium.org>
Reviewed-by: Ian Vollick <vollick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540353}

chrome/browser/android/vr/vr_shell_gl.cc

@@ -1571,7 +1571,7 @@ void VrShellGl::SendVSync(base::TimeTicks time, GetVSyncCallback callback) {
   gfx::Transform head_mat;
   device::mojom::VRPosePtr pose =
       device::GvrDelegate::GetVRPosePtrWithNeckModel(gvr_api_.get(), &head_mat,
-                                                     prediction_nanos);
+                                                     0, prediction_nanos);
 
   webvr_head_pose_[frame_index % kPoseRingBufferSize] = head_mat;
   webvr_frame_oustanding_[frame_index % kPoseRingBufferSize] = true;

device/vr/android/gvr/gvr_delegate.cc

@@ -81,6 +81,12 @@ gfx::Vector3dF GetAngularVelocityFromPoses(gfx::Transform head_mat,
   return omega_vec;
 }
 
+void PostRotateZ(gfx::Transform* transform, float degrees) {
+  gfx::Transform rotate;
+  rotate.RotateAboutZAxis(degrees);
+  transform->ConcatTransform(rotate);
+}
+
 }  // namespace
 
 /* static */
@@ -134,6 +140,7 @@ void GvrDelegate::GetGvrPoseWithNeckModel(gvr::GvrApi* gvr_api,
 mojom::VRPosePtr GvrDelegate::GetVRPosePtrWithNeckModel(
     gvr::GvrApi* gvr_api,
     gfx::Transform* head_mat_out,
+    int rotate_degrees,
     int64_t prediction_time) {
   gvr::ClockTimePoint target_time = gvr::GvrApi::GetTimePointNow();
   target_time.monotonic_system_time_nanos += prediction_time;
@@ -147,6 +154,9 @@ mojom::VRPosePtr GvrDelegate::GetVRPosePtrWithNeckModel(
     head_mat_ptr = &head_mat;
   GvrMatToTransform(gvr_head_mat, head_mat_ptr);
 
+  if (rotate_degrees != 0)
+    PostRotateZ(head_mat_ptr, rotate_degrees);
+
   mojom::VRPosePtr pose = GvrDelegate::VRPosePtrFromGvrPose(*head_mat_ptr);
 
   // Get a second pose a bit later to calculate angular velocity.
@@ -156,6 +166,9 @@ mojom::VRPosePtr GvrDelegate::GetVRPosePtrWithNeckModel(
   gfx::Transform head_mat_2;
   GvrMatToTransform(gvr_head_mat_2, &head_mat_2);
 
+  if (rotate_degrees != 0)
+    PostRotateZ(&head_mat_2, rotate_degrees);
+
   // Add headset angular velocity to the pose.
   pose->angularVelocity.emplace(3);
   double epsilon_seconds = kAngularVelocityEpsilonNanos * 1e-9;
@@ -171,8 +184,9 @@ mojom::VRPosePtr GvrDelegate::GetVRPosePtrWithNeckModel(
 /* static */
 mojom::VRPosePtr GvrDelegate::GetVRPosePtrWithNeckModel(
     gvr::GvrApi* gvr_api,
-    gfx::Transform* head_mat_out) {
-  return GetVRPosePtrWithNeckModel(gvr_api, head_mat_out,
+    gfx::Transform* head_mat_out,
+    int rotate_degrees) {
+  return GetVRPosePtrWithNeckModel(gvr_api, head_mat_out, rotate_degrees,
                                    kPredictionTimeWithoutVsyncNanos);
 }
 

device/vr/android/gvr/gvr_delegate.h

@@ -33,10 +33,12 @@ class DEVICE_VR_EXPORT GvrDelegate {
   static mojom::VRPosePtr GetVRPosePtrWithNeckModel(
       gvr::GvrApi* gvr_api,
       gfx::Transform* head_mat_out,
+      int rotate_degrees,
       int64_t prediction_time);
   static mojom::VRPosePtr GetVRPosePtrWithNeckModel(
       gvr::GvrApi* gvr_api,
-      gfx::Transform* head_mat_out);
+      gfx::Transform* head_mat_out,
+      int rotate_degrees);
 };
 
 }  // namespace device

device/vr/android/gvr/gvr_device.cc

@@ -188,8 +188,8 @@ void GvrDevice::ExitPresent() {
 
 void GvrDevice::OnMagicWindowPoseRequest(
     mojom::VRMagicWindowProvider::GetPoseCallback callback) {
-  std::move(callback).Run(
-      GvrDelegate::GetVRPosePtrWithNeckModel(gvr_api_.get(), nullptr));
+  std::move(callback).Run(GvrDelegate::GetVRPosePtrWithNeckModel(
+      gvr_api_.get(), nullptr, rotation_degrees_));
 }
 
 void GvrDevice::OnListeningForActivate(bool listening) {
@@ -220,6 +220,12 @@ void GvrDevice::OnDIPScaleChanged(JNIEnv* env, const JavaRef<jobject>& obj) {
   SetVRDisplayInfo(CreateVRDisplayInfo(gvr_api_.get(), GetId()));
 }
 
+void GvrDevice::OnRotationChanged(JNIEnv* env,
+                                  const JavaRef<jobject>& obj,
+                                  jint rotation_degrees) {
+  rotation_degrees_ = rotation_degrees;
+}
+
 void GvrDevice::Activate(mojom::VRDisplayEventReason reason,
                          base::Callback<void(bool)> on_handled) {
   OnActivate(reason, std::move(on_handled));

device/vr/android/gvr/gvr_device.h

@@ -38,6 +38,9 @@ class DEVICE_VR_EXPORT GvrDevice : public VRDeviceBase {
 
   void OnDIPScaleChanged(JNIEnv* env,
                          const base::android::JavaRef<jobject>& obj);
+  void OnRotationChanged(JNIEnv* env,
+                         const base::android::JavaRef<jobject>& obj,
+                         jint rotation_degrees);
 
   void Activate(mojom::VRDisplayEventReason reason,
                 base::Callback<void(bool)> on_handled);
@@ -59,6 +62,7 @@ class DEVICE_VR_EXPORT GvrDevice : public VRDeviceBase {
 
   base::android::ScopedJavaGlobalRef<jobject> non_presenting_context_;
   std::unique_ptr<gvr::GvrApi> gvr_api_;
+  int rotation_degrees_;
 
   base::WeakPtrFactory<GvrDevice> weak_ptr_factory_;
 

device/vr/android/java/src/org/chromium/device/vr/NonPresentingGvrContext.java

@@ -7,6 +7,7 @@ package org.chromium.device.vr;
 import android.content.Context;
 import android.os.StrictMode;
 import android.view.Display;
+import android.view.Surface;
 import android.view.WindowManager;
 
 import com.google.vr.cardboard.DisplaySynchronizer;
@@ -46,6 +47,7 @@ public class NonPresentingGvrContext implements DisplayAndroid.DisplayAndroidObs
         }
         mDisplayAndroid = DisplayAndroid.getNonMultiDisplay(context);
         mDisplayAndroid.addObserver(this);
+        onRotationChanged(mDisplayAndroid.getRotation());
     }
 
     @CalledByNative
@@ -69,16 +71,34 @@ public class NonPresentingGvrContext implements DisplayAndroid.DisplayAndroidObs
         mNativeGvrDevice = 0;
     }
 
+    private int rotationToDegrees(int rotation) {
+        switch (rotation) {
+            case Surface.ROTATION_0:
+                return 0;
+            case Surface.ROTATION_90:
+                return 90;
+            case Surface.ROTATION_180:
+                return 180;
+            case Surface.ROTATION_270:
+                return 270;
+        }
+        assert false;
+        return 0;
+    }
+
     @Override
-    public void onRotationChanged(int rotation) {}
+    public void onRotationChanged(int rotation) {
+        if (mNativeGvrDevice != 0) {
+            nativeOnRotationChanged(mNativeGvrDevice, rotationToDegrees(rotation));
+        }
+    }
 
     @Override
     public void onDIPScaleChanged(float dipScale) {
         mGvrApi.refreshDisplayMetrics();
-        if (mNativeGvrDevice != 0) {
-            nativeOnDIPScaleChanged(mNativeGvrDevice);
-        }
+        if (mNativeGvrDevice != 0) nativeOnDIPScaleChanged(mNativeGvrDevice);
     }
 
     private native void nativeOnDIPScaleChanged(long nativeGvrDevice);
+    private native void nativeOnRotationChanged(long nativeGvrDevice, int rotationDegrees);
 }