format

Author: Chris Yang

flow/embedded_views.cc

@@ -101,9 +101,9 @@ void MutatorsStack::PushOpacity(const int& alpha) {
 
 void MutatorsStack::PushBackdropFilter(
     const std::shared_ptr<const DlImageFilter>& filter,
-    const SkRect& paint_bounds) {
+    const SkRect& filter_rect) {
   std::shared_ptr<Mutator> element =
-      std::make_shared<Mutator>(filter, paint_bounds);
+      std::make_shared<Mutator>(filter, filter_rect);
   vector_.push_back(element);
 };
 

flow/embedded_views.h

@@ -38,22 +38,25 @@ enum MutatorType {
 // TODO(cyanglaz): Refactor this into a ImageFilterMutator class.
 //  https://github.com/flutter/flutter/issues/108470
 class ImageFilterMutation {
-  public:
-    ImageFilterMutation(std::shared_ptr<const DlImageFilter> filter, const SkRect& paint_bounds):filter_(filter), paint_bounds_(paint_bounds){}
+ public:
+  ImageFilterMutation(std::shared_ptr<const DlImageFilter> filter,
+                      const SkRect& filter_rect)
+      : filter_(filter), filter_rect_(filter_rect) {}
 
-    const DlImageFilter& GetFilter() const { return *filter_; }
-    const SkRect& GetPaintBounds() const { return paint_bounds_; }
+  const DlImageFilter& GetFilter() const { return *filter_; }
+  const SkRect& GetFilterRect() const { return filter_rect_; }
 
-    bool operator==(const ImageFilterMutation& other) const {
-      return *filter_ == *other.filter_ && paint_bounds_ == other.paint_bounds_;
-    }
+  bool operator==(const ImageFilterMutation& other) const {
+    return *filter_ == *other.filter_ && filter_rect_ == other.filter_rect_;
+  }
 
-    bool operator!=(const ImageFilterMutation& other) const { return !operator==(other); }
+  bool operator!=(const ImageFilterMutation& other) const {
+    return !operator==(other);
+  }
 
-  private:
-    std::shared_ptr<const DlImageFilter> filter_;
-    // Used for filter_
-    const SkRect& paint_bounds_;
+ private:
+  std::shared_ptr<const DlImageFilter> filter_;
+  const SkRect filter_rect_;
 };
 
 // Stores mutation information like clipping or kTransform.
@@ -97,8 +100,10 @@ class Mutator {
   explicit Mutator(const SkMatrix& matrix)
       : type_(kTransform), matrix_(matrix) {}
   explicit Mutator(const int& alpha) : type_(kOpacity), alpha_(alpha) {}
-  explicit Mutator(std::shared_ptr<const DlImageFilter> filter,  const SkRect& paint_bounds)
-      : type_(kBackdropFilter), filter_(std::make_shared<ImageFilterMutation>(filter, paint_bounds)) {}
+  explicit Mutator(std::shared_ptr<const DlImageFilter> filter,
+                   const SkRect& filter_rect)
+      : type_(kBackdropFilter),
+        filter_(std::make_shared<ImageFilterMutation>(filter, filter_rect)) {}
 
   const MutatorType& GetType() const { return type_; }
   const SkRect& GetRect() const { return rect_; }
@@ -177,8 +182,8 @@ class MutatorsStack {
   void PushClipPath(const SkPath& path);
   void PushTransform(const SkMatrix& matrix);
   void PushOpacity(const int& alpha);
-  void PushBackdropFilter(const std::shared_ptr<const DlImageFilter>const filter,
-                          const SkRect& paint_bounds);
+  void PushBackdropFilter(const std::shared_ptr<const DlImageFilter>& filter,
+                          const SkRect& filter_rect);
 
   // Removes the `Mutator` on the top of the stack
   // and destroys it.
@@ -273,8 +278,9 @@ class EmbeddedViewParams {
   const SkRect& finalBoundingRect() const { return final_bounding_rect_; }
 
   // Pushes the stored DlImageFilter object to the mutators stack.
-  void PushImageFilter(std::shared_ptr<const DlImageFilter> filter, const SkRect& paint_bounds) {
-    mutators_stack_.PushBackdropFilter(filter, paint_bounds);
+  void PushImageFilter(std::shared_ptr<const DlImageFilter> filter,
+                       const SkRect& filter_rect) {
+    mutators_stack_.PushBackdropFilter(filter, filter_rect);
   }
 
   // Whether the embedder should construct DisplayList objects to hold the
@@ -478,7 +484,8 @@ class ExternalViewEmbedder {
   // See also: |PushVisitedPlatformView| for pushing platform view ids to the
   // visited platform views list.
   virtual void PushFilterToVisitedPlatformViews(
-      std::shared_ptr<const DlImageFilter> filter, const SkRect& paint_bounds) {}
+      std::shared_ptr<const DlImageFilter> filter,
+      const SkRect& filter_rect) {}
 
  private:
   bool used_this_frame_ = false;

flow/layers/backdrop_filter_layer.cc

@@ -49,8 +49,8 @@ void BackdropFilterLayer::Preroll(PrerollContext* context,
   set_paint_bounds(child_paint_bounds);
   context->subtree_can_inherit_opacity = true;
   if (context->view_embedder != nullptr) {
-    context->view_embedder->PushFilterToVisitedPlatformViews(filter_,
-                                                             paint_bounds());
+    context->view_embedder->PushFilterToVisitedPlatformViews(
+        filter_, context->cull_rect);
   }
 }
 

shell/common/shell_test_external_view_embedder.cc

@@ -90,10 +90,10 @@ void ShellTestExternalViewEmbedder::PushVisitedPlatformView(int64_t view_id) {
 // |ExternalViewEmbedder|
 void ShellTestExternalViewEmbedder::PushFilterToVisitedPlatformViews(
     std::shared_ptr<const DlImageFilter> filter,
-    const SkRect& paint_bounds) {
+    const SkRect& filter_rect) {
   for (int64_t id : visited_platform_views_) {
     EmbeddedViewParams params = current_composition_params_[id];
-    params.PushImageFilter(filter, paint_bounds);
+    params.PushImageFilter(filter, filter_rect);
     current_composition_params_[id] = params;
     mutators_stacks_[id] = params.mutatorsStack();
   }

shell/common/shell_test_external_view_embedder.h

@@ -77,7 +77,7 @@ class ShellTestExternalViewEmbedder final : public ExternalViewEmbedder {
   // |ExternalViewEmbedder|
   void PushFilterToVisitedPlatformViews(
       std::shared_ptr<const DlImageFilter> filter,
-      const SkRect& paint_bounds) override;
+      const SkRect& filter_rect) override;
 
   // |ExternalViewEmbedder|
   void SubmitFrame(GrDirectContext* context,

shell/platform/darwin/ios/framework/Source/FlutterPlatformViews.mm

@@ -323,10 +323,10 @@ - (BOOL)flt_hasFirstResponderInViewHierarchySubtree {
 
 void FlutterPlatformViewsController::PushFilterToVisitedPlatformViews(
     std::shared_ptr<const DlImageFilter> filter,
-    const SkRect& paint_bounds) {
+    const SkRect& filter_rect) {
   for (int64_t id : visited_platform_views_) {
     EmbeddedViewParams params = current_composition_params_[id];
-    params.PushImageFilter(filter, paint_bounds);
+    params.PushImageFilter(filter, filter_rect);
     current_composition_params_[id] = params;
   }
 }
@@ -431,7 +431,7 @@ - (BOOL)flt_hasFirstResponderInViewHierarchySubtree {
                                CGRectGetWidth(flutter_view.bounds),
                                CGRectGetHeight(flutter_view.bounds))] autorelease];
 
-  NSMutableArray* blurRadii = [[[NSMutableArray alloc] init] autorelease];
+  NSMutableArray* blurFilters = [[[NSMutableArray alloc] init] autorelease];
 
   auto iter = mutators_stack.Begin();
   while (iter != mutators_stack.End()) {
@@ -460,7 +460,18 @@ - (BOOL)flt_hasFirstResponderInViewHierarchySubtree {
           // sigma_x and sigma_y equal to each other. DlBlurImageFilter's Tile Mode
           // is not supported in Quartz's gaussianBlur CAFilter, so it is not used
           // to blur the PlatformView.
-          [blurRadii addObject:@((*iter)->GetFilter().GetFilter().asBlur()->sigma_x())];
+          CGFloat blurRadius = (*iter)->GetFilter().GetFilter().asBlur()->sigma_x();
+          CGRect filterRect = flutter::GetCGRectFromSkRect((*iter)->GetFilter().GetFilterRect());
+          // `filterRect` reprents the rect that shouuld be filtered inside the `flutter_view_`.
+          // The `PlatformViewFilter` needs the frame inside the `clipView` that needs to be
+          // filtered.
+          CGRect intersection = CGRectIntersection(filterRect, clipView.frame);
+          if (CGRectContainsRect(clipView.frame, intersection)) {
+            CGRect frameInClipView = [flutter_view_.get() convertRect:intersection toView:clipView];
+            PlatformViewFilter* filter = [[PlatformViewFilter alloc] initWithFrame:frameInClipView
+                                                                        blurRadius:blurRadius];
+            [blurFilters addObject:filter];
+          }
         }
         break;
       }
@@ -469,8 +480,7 @@ - (BOOL)flt_hasFirstResponderInViewHierarchySubtree {
   }
 
   if (canApplyBlurBackdrop) {
-    canApplyBlurBackdrop = [clipView applyBlurBackdropFilters:blurRadii
-                                                      atFrame:CGRectMake(50, 50, 200, 200)];
+    canApplyBlurBackdrop = [clipView applyBlurBackdropFilters:blurFilters];
   }
 
   // Reverse the offset of the clipView.

shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h

@@ -48,36 +48,26 @@
 // An object represents a filter.
 @interface PlatformViewFilter : NSObject
 
-@property(assign, nonatomic) CGRect frame;
-@property(assign, nonatomic) CGFloat blurRadius;
-
-- (void)initWithFrame:(CGRect)frame blurRadius:(CGFloat)blurRadius;
-
-@end
-
-// A view that applies filter to the |ChildClippingView|.
-//
-// The filter information is provided with a single |PlatformViewFilter|.
-@interface PlatformViewFilterView : UIView
+@property(assign, nonatomic, readonly) CGRect frame;
+@property(assign, nonatomic, readonly) CGFloat blurRadius;
+// The UIView used to extract the gaussianBlur filter. This must be a UIVisualEffectView
+// initalized with UIBlurEffect to extract the correct filter. Made a public property
+// for custom unit tests.
+@property(nonatomic, retain) UIView* blurEffectView;
 
-// Applies blur backdrop filters to the PlatformViewFilterView with blur radius values from
-// blurRadii.
-- (void)applyBlurBackdropFilters:(NSArray*)blurRadii gaussianFilter:(NSObject*)gaussianFilter;
+- (instancetype)initWithFrame:(CGRect)frame blurRadius:(CGFloat)blurRadius;
+// Returns the blur backdrop filter view based on the `frame` and `blurRadius` property.
+- (UIView*)backdropFilterView;
 
 @end
 
 // The parent view handles clipping to its subviews.
 @interface ChildClippingView : UIView
 
-// The UIView used to extract the gaussianBlur filter. This must be a UIVisualEffectView
-// initalized with UIBlurEffect to extract the correct filter. Made a public property
-// for custom unit tests.
-@property(nonatomic, retain) UIView* blurEffectView;
-
 // Applies blur backdrop filters to the ChildClippingView with blur radius values from
 // blurRadii. Returns NO if Apple's API has changed and blurred backdrop filters cannot
 // be applied, otherwise returns YES.
-- (BOOL)applyBlurBackdropFilters:(NSArray*)blurRadii atFrame:(CGRect)frame;
+- (BOOL)applyBlurBackdropFilters:(NSMutableArray<PlatformViewFilter*>*)filters;
 
 @end
 
@@ -90,6 +80,8 @@ CATransform3D GetCATransform3DFromSkMatrix(const SkMatrix& matrix);
 // The position of the `layer` should be unchanged after resetting the anchor.
 void ResetAnchor(CALayer* layer);
 
+CGRect GetCGRectFromSkRect(const SkRect& clipSkRect);
+
 class IOSContextGL;
 class IOSSurface;
 
@@ -219,7 +211,7 @@ class FlutterPlatformViewsController {
 
   // Pushes backdrop filter mutation to the mutator stack of each visited platform view.
   void PushFilterToVisitedPlatformViews(std::shared_ptr<const DlImageFilter> filter,
-                                        const SkRect& paint_bounds);
+                                        const SkRect& filter_rect);
 
   // Pushes the view id of a visted platform view to the list of visied platform views.
   void PushVisitedPlatformView(int64_t view_id) { visited_platform_views_.push_back(view_id); }