Fix surface resize bugs

Author: Emmanuel Garcia

shell/common/rasterizer.cc

@@ -377,12 +377,6 @@ RasterStatus Rasterizer::DrawToSurface(flutter::LayerTree& layer_tree) {
   TRACE_EVENT0("flutter", "Rasterizer::DrawToSurface");
   FML_DCHECK(surface_);
 
-  auto frame = surface_->AcquireFrame(layer_tree.frame_size());
-
-  if (frame == nullptr) {
-    return RasterStatus::kFailed;
-  }
-
   // There is no way for the compositor to know how long the layer tree
   // construction took. Fortunately, the layer tree does. Grab that time
   // for instrumentation.
@@ -398,6 +392,12 @@ RasterStatus Rasterizer::DrawToSurface(flutter::LayerTree& layer_tree) {
     embedder_root_canvas = external_view_embedder->GetRootCanvas();
   }
 
+  auto frame = surface_->AcquireFrame(layer_tree.frame_size());
+
+  if (frame == nullptr) {
+    return RasterStatus::kFailed;
+  }
+
   // If the external view embedder has specified an optional root surface, the
   // root surface transformation is set by the embedder instead of
   // having to apply it here.

shell/platform/android/external_view_embedder/external_view_embedder.cc

@@ -142,12 +142,15 @@ bool AndroidExternalViewEmbedder::SubmitFrame(
     background_canvas->drawPicture(pictures.at(view_id));
   }
   // Submit the background canvas frame before switching the GL context to
-  // the surfaces above.
+  // the overlay surfaces.
+  //
+  // Skip a frame if the embedding is switching surfaces.
   auto should_submit_current_frame =
       previous_frame_view_count_ > 0 || current_frame_view_count == 0;
   if (should_submit_current_frame) {
     frame->Submit();
   }
+
   for (int64_t view_id : composition_order_) {
     SkRect view_rect = GetViewRect(view_id);
     // Display the platform view. If it's already displayed, then it's
@@ -159,12 +162,14 @@ bool AndroidExternalViewEmbedder::SubmitFrame(
                                                   view_rect.height()  //
     );
     for (const SkRect& overlay_rect : overlay_layers.at(view_id)) {
-      CreateSurfaceIfNeeded(context,               //
-                            view_id,               //
-                            pictures.at(view_id),  //
-                            overlay_rect           //
-                            )
-          ->Submit();
+      auto frame = CreateSurfaceIfNeeded(context,               //
+                                         view_id,               //
+                                         pictures.at(view_id),  //
+                                         overlay_rect           //
+      );
+      if (should_submit_current_frame) {
+        frame->Submit();
+      }
     }
   }
   return true;
@@ -244,6 +249,9 @@ void AndroidExternalViewEmbedder::BeginFrame(
     double device_pixel_ratio,
     fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   Reset();
+
+  // The surface size changed. Therefore, destroy existing surfaces as
+  // the existing surfaces in the pool can't be recycled.
   if (frame_size_ != frame_size) {
     surface_pool_->DestroyLayers(jni_facade_);
   }

shell/platform/android/io/flutter/embedding/android/FlutterImageView.java

@@ -194,14 +194,25 @@ public boolean acquireLatestImage() {
 
   /** Creates a new image reader with the provided size. */
   public void resizeIfNeeded(int width, int height) {
+    if (flutterRenderer == null) {
+      return;
+    }
     if (width == imageReader.getWidth() && height == imageReader.getHeight()) {
       return;
     }
-    if (kind == SurfaceKind.background && flutterRenderer != null) {
-      imageReader.close();
-      imageReader = createImageReader(width, height);
-      flutterRenderer.swapSurface(imageReader.getSurface());
+    // Close resources.
+    if (nextImage != null) {
+      nextImage.close();
+      nextImage = null;
     }
+    if (currentImage != null) {
+      currentImage.close();
+      currentImage = null;
+    }
+    imageReader.close();
+    // Image readers cannot be resized once created.
+    imageReader = createImageReader(width, height);
+    pendingImages = 0;
   }
 
   @Override
@@ -251,6 +262,16 @@ private void updateCurrentBitmap() {
 
   @Override
   protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
-    resizeIfNeeded(width, height);
+    // `SurfaceKind.overlay` isn't resized. Instead, the `FlutterImageView` instance
+    // is destroyed. As a result, an instance with the new size is created by the surface
+    // pool in the native side.
+    if (kind == SurfaceKind.background && isAttachedToFlutterRenderer) {
+      if (width != imageReader.getWidth() || height != imageReader.getHeight()) {
+        resizeIfNeeded(width, height);
+        // Bind native window to the new surface, and create a new onscreen surface
+        // with the new size in the native side.
+        flutterRenderer.swapSurface(imageReader.getSurface());
+      }
+    }
   }
 }

shell/platform/android/io/flutter/plugin/platform/PlatformViewsController.java

@@ -710,9 +710,9 @@ public void onEndFrame() {
       FlutterImageView overlayView = overlayLayerViews.valueAt(i);
 
       if (currentFrameUsedOverlayLayerIds.contains(overlayId)) {
+        ((FlutterView) flutterView).attachOverlaySurfaceToRender(overlayView);
         boolean didAcquireOverlaySurfaceImage = overlayView.acquireLatestImage();
         isFrameRenderedUsingImageReaders &= didAcquireOverlaySurfaceImage;
-        ((FlutterView) flutterView).attachOverlaySurfaceToRender(overlayView);
       } else {
         // If the background surface isn't rendered by the image view, then the
         // overlay surfaces can be detached from the rendered.
@@ -763,6 +763,12 @@ public FlutterOverlaySurface createOverlaySurface() {
   }
 
   public void destroyOverlaySurfaces() {
+    for (int i = 0; i < overlayLayerViews.size(); i++) {
+      int overlayId = overlayLayerViews.keyAt(i);
+      FlutterImageView overlayView = overlayLayerViews.valueAt(i);
+      overlayView.detachFromRenderer();
+      ((FlutterView) flutterView).removeView(overlayView);
+    }
     overlayLayerViews.clear();
   }
 }