Frame subscriber bugfix + added only_damaged option

atom/browser/api/atom_api_web_contents.cc

@@ -1195,11 +1195,18 @@ void WebContents::SendInputEvent(v8::Isolate* isolate,
 }
 
 void WebContents::BeginFrameSubscription(
-    const FrameSubscriber::FrameCaptureCallback& callback) {
+  mate::Arguments* args) {
+  FrameSubscriber::FrameCaptureCallback callback;
+  if (!args->GetNext(&callback))
+    return;
+
+  bool only_damaged = false;
+  args->GetNext(&only_damaged);
+
   const auto view = web_contents()->GetRenderWidgetHostView();
   if (view) {
     std::unique_ptr<FrameSubscriber> frame_subscriber(new FrameSubscriber(
-        isolate(), view, callback));
+        isolate(), view, callback, only_damaged));
     view->BeginFrameSubscription(std::move(frame_subscriber));
   }
 }

atom/browser/api/atom_api_web_contents.h

@@ -139,8 +139,7 @@ class WebContents : public mate::TrackableObject<WebContents>,
   void SendInputEvent(v8::Isolate* isolate, v8::Local<v8::Value> input_event);
 
   // Subscribe to the frame updates.
-  void BeginFrameSubscription(
+  void BeginFrameSubscription(mate::Arguments* args);
-      const FrameSubscriber::FrameCaptureCallback& callback);
   void EndFrameSubscription();
 
   // Methods for creating <webview>.

atom/browser/api/frame_subscriber.cc

@@ -6,6 +6,7 @@
 
 #include "base/bind.h"
 #include "atom/common/node_includes.h"
+#include "atom/common/native_mate_converters/gfx_converter.h"
 #include "content/public/browser/render_widget_host.h"
 
 namespace atom {
@@ -14,8 +15,10 @@ namespace api {
 
 FrameSubscriber::FrameSubscriber(v8::Isolate* isolate,
                                  content::RenderWidgetHostView* view,
-                                 const FrameCaptureCallback& callback)
+                                 const FrameCaptureCallback& callback,
-    : isolate_(isolate), view_(view), callback_(callback), weak_factory_(this) {
+                                 const bool& only_damaged)
+    : isolate_(isolate), view_(view), only_damaged_(only_damaged),
+      callback_(callback), weak_factory_(this) {
 }
 
 bool FrameSubscriber::ShouldCaptureFrame(
@@ -27,21 +30,27 @@ bool FrameSubscriber::ShouldCaptureFrame(
   if (!view_ || !host)
     return false;
 
-  const auto size = view_->GetVisibleViewportSize();
+  if (damage_rect.width() == 0 || damage_rect.height() == 0)
+    return false;
+
+  gfx::Rect rect = gfx::Rect(view_->GetVisibleViewportSize());
+  if (only_damaged_)
+    rect = damage_rect;
 
   host->CopyFromBackingStore(
-      gfx::Rect(size),
+      rect,
-      size,
+      rect.size(),
       base::Bind(&FrameSubscriber::OnFrameDelivered,
-                 weak_factory_.GetWeakPtr(), callback_),
+                 weak_factory_.GetWeakPtr(), callback_, rect),
       kBGRA_8888_SkColorType);
 
   return false;
 }
 
 void FrameSubscriber::OnFrameDelivered(const FrameCaptureCallback& callback,
-  const SkBitmap& bitmap, content::ReadbackResponse response) {
+  const gfx::Rect& damage_rect, const SkBitmap& bitmap,
-  if (bitmap.computeSize64() == 0)
+  content::ReadbackResponse response) {
+  if (response != content::ReadbackResponse::READBACK_SUCCESS)
     return;
 
   v8::Locker locker(isolate_);
@@ -57,7 +66,10 @@ void FrameSubscriber::OnFrameDelivered(const FrameCaptureCallback& callback,
     reinterpret_cast<uint8_t*>(node::Buffer::Data(buffer.ToLocalChecked())),
     rgb_arr_size);
 
-  callback_.Run(buffer.ToLocalChecked());
+  v8::Local<v8::Value> damage =
+    mate::Converter<gfx::Rect>::ToV8(isolate_, damage_rect);
+
+  callback_.Run(buffer.ToLocalChecked(), damage);
 }
 
 }  // namespace api

atom/browser/api/frame_subscriber.h

@@ -20,11 +20,13 @@ namespace api {
 
 class FrameSubscriber : public content::RenderWidgetHostViewFrameSubscriber {
  public:
-  using FrameCaptureCallback = base::Callback<void(v8::Local<v8::Value>)>;
+  using FrameCaptureCallback =
+    base::Callback<void(v8::Local<v8::Value>, v8::Local<v8::Value>)>;
 
   FrameSubscriber(v8::Isolate* isolate,
                   content::RenderWidgetHostView* view,
-                  const FrameCaptureCallback& callback);
+                  const FrameCaptureCallback& callback,
+                  const bool& only_damaged);
 
   bool ShouldCaptureFrame(const gfx::Rect& damage_rect,
                           base::TimeTicks present_time,
@@ -33,11 +35,13 @@ class FrameSubscriber : public content::RenderWidgetHostViewFrameSubscriber {
 
  private:
   void OnFrameDelivered(const FrameCaptureCallback& callback,
-    const SkBitmap& bitmap, content::ReadbackResponse response);
+    const gfx::Rect& damage_rect, const SkBitmap& bitmap,
+    content::ReadbackResponse response);
 
   v8::Isolate* isolate_;
   content::RenderWidgetHostView* view_;
   FrameCaptureCallback callback_;
+  bool only_damaged_;
 
   base::WeakPtrFactory<FrameSubscriber> weak_factory_;