Fuchsia: Fix size & position of test window on Scenic

util/fuchsia/ScenicWindow.cpp

@@ -72,6 +72,7 @@ ScenicWindow::ScenicWindow()
       mMaterial(&mScenicSession)
 {
     mScenicSession.set_error_handler(fit::bind_member(this, &ScenicWindow::onScenicError));
+    mScenicSession.set_event_handler(fit::bind_member(this, &ScenicWindow::onScenicEvents));
     mScenicSession.set_on_frame_presented_handler(
         fit::bind_member(this, &ScenicWindow::onFramePresented));
 }
@@ -84,7 +85,7 @@ ScenicWindow::~ScenicWindow()
 bool ScenicWindow::initialize(const std::string &name, int width, int height)
 {
     // Set up scenic resources.
-    mShape.SetShape(scenic::Rectangle(&mScenicSession, width, height));
+    mShape.SetEventMask(fuchsia::ui::gfx::kMetricsEventMask);
     mShape.SetMaterial(mMaterial);
 
     fuchsia::ui::views::ViewToken viewToken;
@@ -103,6 +104,13 @@ bool ScenicWindow::initialize(const std::string &name, int width, int height)
 
     resetNativeWindow();
 
+    // Block until initial view dimensions are known.
+    while (!mHasViewMetrics && !mHasViewProperties && !mLostSession)
+    {
+        mLoop->ResetQuit();
+        mLoop->Run(zx::time::infinite(), true /* once */);
+    }
+
     return true;
 }
 
@@ -168,6 +176,10 @@ bool ScenicWindow::resize(int width, int height)
 
     fuchsia_egl_window_resize(mFuchsiaEGLWindow.get(), width, height);
 
+    mViewSizeDirty = true;
+
+    updateViewSize();
+
     return true;
 }
 
@@ -203,7 +215,29 @@ void ScenicWindow::onFramePresented(fuchsia::scenic::scheduling::FramePresentedI
 
 void ScenicWindow::onScenicEvents(std::vector<fuchsia::ui::scenic::Event> events)
 {
-    UNIMPLEMENTED();
+    for (const auto &event : events)
+    {
+        if (event.is_gfx())
+        {
+            if (event.gfx().is_metrics())
+            {
+                if (event.gfx().metrics().node_id != mShape.id())
+                    continue;
+                onViewMetrics(event.gfx().metrics().metrics);
+            }
+            else if (event.gfx().is_view_properties_changed())
+            {
+                if (event.gfx().view_properties_changed().view_id != mView->id())
+                    continue;
+                onViewProperties(event.gfx().view_properties_changed().properties);
+            }
+        }
+    }
+
+    if (mViewSizeDirty)
+    {
+        updateViewSize();
+    }
 }
 
 void ScenicWindow::onScenicError(zx_status_t status)
@@ -213,6 +247,52 @@ void ScenicWindow::onScenicError(zx_status_t status)
     mLoop->Quit();
 }
 
+void ScenicWindow::onViewMetrics(const fuchsia::ui::gfx::Metrics &metrics)
+{
+    mDisplayScaleX = metrics.scale_x;
+    mDisplayScaleY = metrics.scale_y;
+
+    mHasViewMetrics = true;
+    mViewSizeDirty  = true;
+}
+
+void ScenicWindow::onViewProperties(const fuchsia::ui::gfx::ViewProperties &properties)
+{
+    float width = properties.bounding_box.max.x - properties.bounding_box.min.x -
+                  properties.inset_from_min.x - properties.inset_from_max.x;
+    float height = properties.bounding_box.max.y - properties.bounding_box.min.y -
+                   properties.inset_from_min.y - properties.inset_from_max.y;
+
+    mDisplayWidthDips  = width;
+    mDisplayHeightDips = height;
+
+    mHasViewProperties = true;
+    mViewSizeDirty     = true;
+}
+
+void ScenicWindow::updateViewSize()
+{
+    if (!mViewSizeDirty || !mHasViewMetrics || !mHasViewProperties)
+    {
+        return;
+    }
+
+    mViewSizeDirty = false;
+
+    // Surface size in pixels is
+    //   (mWidth, mHeight)
+    //
+    // View size in pixels is
+    //   (mDisplayWidthDips * mDisplayScaleX) x (mDisplayHeightDips * mDisplayScaleY)
+
+    float widthDips  = mWidth / mDisplayScaleX;
+    float heightDips = mHeight / mDisplayScaleY;
+
+    mShape.SetShape(scenic::Rectangle(&mScenicSession, widthDips, heightDips));
+    mShape.SetTranslation(0.5f * widthDips, 0.5f * heightDips, 0.f);
+    present();
+}
+
 // static
 OSWindow *OSWindow::New()
 {

util/fuchsia/ScenicWindow.h

@@ -63,8 +63,12 @@ class ANGLE_UTIL_EXPORT ScenicWindow : public OSWindow
     void onScenicEvents(std::vector<fuchsia::ui::scenic::Event> events);
     void onScenicError(zx_status_t status);
     void onFramePresented(fuchsia::scenic::scheduling::FramePresentedInfo info);
+    void onViewMetrics(const fuchsia::ui::gfx::Metrics &metrics);
+    void onViewProperties(const fuchsia::ui::gfx::ViewProperties &properties);
 
   private:
+    void updateViewSize();
+
     // ScenicWindow async loop.
     async::Loop *const mLoop;
 
@@ -88,6 +92,15 @@ class ANGLE_UTIL_EXPORT ScenicWindow : public OSWindow
     // Scenic view.
     std::unique_ptr<scenic::View> mView;
 
+    // View geometry.
+    float mDisplayHeightDips = 0.f;
+    float mDisplayWidthDips  = 0.f;
+    float mDisplayScaleX     = 0.f;
+    float mDisplayScaleY     = 0.f;
+    bool mHasViewProperties  = false;
+    bool mHasViewMetrics     = false;
+    bool mViewSizeDirty      = false;
+
     // EGL native window.
     std::unique_ptr<fuchsia_egl_window, FuchsiaEGLWindowDeleter> mFuchsiaEGLWindow;
 };