adds scale factor check and simplifies frame subscription

atom/browser/api/atom_api_web_contents.cc

@@ -1242,7 +1242,7 @@ void WebContents::BeginFrameSubscription(mate::Arguments* args) {
   const auto view = web_contents()->GetRenderWidgetHostView();
   if (view) {
     std::unique_ptr<FrameSubscriber> frame_subscriber(new FrameSubscriber(
-        isolate(), view, callback, only_dirty));
+        view, callback, only_dirty));
     view->BeginFrameSubscription(std::move(frame_subscriber));
   }
 }

atom/browser/api/frame_subscriber.cc

@@ -8,17 +8,17 @@
 #include "atom/common/node_includes.h"
 #include "base/bind.h"
 #include "content/public/browser/render_widget_host.h"
+#include "ui/display/screen.h"
+#include "ui/display/display.h"
 
 namespace atom {
 
 namespace api {
 
-FrameSubscriber::FrameSubscriber(v8::Isolate* isolate,
-                                 content::RenderWidgetHostView* view,
+FrameSubscriber::FrameSubscriber(content::RenderWidgetHostView* view,
                                  const FrameCaptureCallback& callback,
                                  bool only_dirty)
-    : isolate_(isolate),
-      view_(view),
+    : view_(view),
       callback_(callback),
       only_dirty_(only_dirty),
       weak_factory_(this) {
@@ -40,6 +40,17 @@ bool FrameSubscriber::ShouldCaptureFrame(
   if (only_dirty_)
     rect = dirty_rect;
 
+  gfx::Size view_size = rect.size();
+  gfx::Size bitmap_size = view_size;
+  const gfx::NativeView native_view = view_->GetNativeView();
+  const float scale =
+      display::Screen::GetScreen()->GetDisplayNearestWindow(native_view)
+      .device_scale_factor();
+  if (scale > 1.0f)
+    bitmap_size = gfx::ScaleToCeiledSize(view_size, scale);
+
+  rect = gfx::Rect(rect.origin(), bitmap_size);
+
   host->CopyFromBackingStore(
       rect,
       rect.size(),
@@ -57,23 +68,7 @@ void FrameSubscriber::OnFrameDelivered(const FrameCaptureCallback& callback,
   if (response != content::ReadbackResponse::READBACK_SUCCESS)
     return;
 
-  v8::Locker locker(isolate_);
-  v8::HandleScope handle_scope(isolate_);
-
-  size_t rgb_arr_size = bitmap.width() * bitmap.height() *
-    bitmap.bytesPerPixel();
-  v8::MaybeLocal<v8::Object> buffer = node::Buffer::New(isolate_, rgb_arr_size);
-  if (buffer.IsEmpty())
-    return;
-
-  bitmap.copyPixelsTo(
-    reinterpret_cast<uint8_t*>(node::Buffer::Data(buffer.ToLocalChecked())),
-    rgb_arr_size);
-
-  v8::Local<v8::Value> damage =
-      mate::Converter<gfx::Rect>::ToV8(isolate_, damage_rect);
-
-  callback_.Run(buffer.ToLocalChecked(), damage);
+  callback.Run(gfx::Image::CreateFrom1xBitmap(bitmap), damage_rect);
 }
 
 }  // namespace api

atom/browser/api/frame_subscriber.h

@@ -11,8 +11,8 @@
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/render_widget_host_view_frame_subscriber.h"
 #include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/gfx/image/image.h"
 #include "ui/gfx/geometry/size.h"
-#include "v8/include/v8.h"
 
 namespace atom {
 
@@ -21,10 +21,9 @@ namespace api {
 class FrameSubscriber : public content::RenderWidgetHostViewFrameSubscriber {
  public:
   using FrameCaptureCallback =
-      base::Callback<void(v8::Local<v8::Value>, v8::Local<v8::Value>)>;
+      base::Callback<void(const gfx::Image&, const gfx::Rect&)>;
 
-  FrameSubscriber(v8::Isolate* isolate,
-                  content::RenderWidgetHostView* view,
+  FrameSubscriber(content::RenderWidgetHostView* view,
                   const FrameCaptureCallback& callback,
                   bool only_dirty);
 
@@ -39,7 +38,6 @@ class FrameSubscriber : public content::RenderWidgetHostViewFrameSubscriber {
                         const SkBitmap& bitmap,
                         content::ReadbackResponse response);
 
-  v8::Isolate* isolate_;
   content::RenderWidgetHostView* view_;
   FrameCaptureCallback callback_;
   bool only_dirty_;