Make software compositing work on Mac.

content/browser/renderer_host/software_framebuffer.cc

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "software_framebuffer.h"
+
+#include "cc/output/compositor_frame_ack.h"
+#include "content/browser/renderer_host/dip_util.h"
+#include "content/browser/renderer_host/frame_memory_manager.h"
+#include "content/public/browser/render_process_host.h"
+
+namespace content {
+
+class MemoryHolder : public base::RefCounted<MemoryHolder> {
+ public:
+  MemoryHolder(scoped_ptr<base::SharedMemory> shared_memory,
+               gfx::Size frame_size,
+               float frame_scale_factor,
+               base::Callback<void()> callback)
+      : shared_memory_(shared_memory.Pass()),
+        frame_size_(frame_size),
+        frame_scale_factor_(frame_scale_factor),
+        callback_(callback) {}
+
+  void GetMailbox(cc::TextureMailbox* mailbox,
+                  scoped_ptr<cc::SingleReleaseCallback>* release_callback) {
+    *mailbox = cc::TextureMailbox(shared_memory_.get(), frame_size_);
+    *release_callback = cc::SingleReleaseCallback::Create(
+        base::Bind(ReleaseMailbox, make_scoped_refptr(this)));
+  }
+  const gfx::Size& GetSizeInPixels() const { return frame_size_; }
+  float GetScaleFactor() const { return frame_scale_factor_; }
+  const void* GetPixels() const { return shared_memory_->memory(); }
+
+ private:
+  friend class base::RefCounted<MemoryHolder>;
+  ~MemoryHolder() { callback_.Run(); }
+
+  static void ReleaseMailbox(scoped_refptr<MemoryHolder> holder,
+                             unsigned sync_point,
+                             bool lost_resource) {}
+
+  scoped_ptr<base::SharedMemory> shared_memory_;
+  gfx::Size frame_size_;
+  float frame_scale_factor_;
+  base::Callback<void()> callback_;
+};
+
+SoftwareFramebuffer::SoftwareFramebuffer(
+    SoftwareFramebufferClient* client,
+    RenderWidgetHostImpl* render_widget_host_impl)
+      : client_(client), render_widget_host_impl_(render_widget_host_impl) {}
+
+SoftwareFramebuffer::~SoftwareFramebuffer() {
+  client_ = NULL;
+  render_widget_host_impl_ = NULL;
+  DiscardCurrentFrame();
+}
+
+void SoftwareFramebuffer::WasShown() {
+  if (framebuffer_holder_)
+    FrameMemoryManager::GetInstance()->SetFrameVisibility(this, true);
+}
+
+void SoftwareFramebuffer::WasHidden() {
+  if (framebuffer_holder_)
+    FrameMemoryManager::GetInstance()->SetFrameVisibility(this, false);
+}
+
+void SoftwareFramebuffer::DiscardCurrentFrame() {
+  FrameMemoryManager::GetInstance()->RemoveFrame(this);
+  framebuffer_holder_ = NULL;
+}
+
+void SoftwareFramebuffer::GetCurrentFrameMailbox(
+    cc::TextureMailbox* mailbox,
+    scoped_ptr<cc::SingleReleaseCallback>* release_callback) const {
+  DCHECK(framebuffer_holder_);
+  return framebuffer_holder_->GetMailbox(mailbox,
+      release_callback);
+}
+
+gfx::Size SoftwareFramebuffer::GetCurrentFrameSizeInPixels() const {
+  DCHECK(framebuffer_holder_);
+  return framebuffer_holder_->GetSizeInPixels();
+}
+
+gfx::Size SoftwareFramebuffer::GetCurrentFrameSizeInDIP() const {
+  DCHECK(framebuffer_holder_);
+  return ConvertSizeToDIP(framebuffer_holder_->GetScaleFactor(),
+                          framebuffer_holder_->GetSizeInPixels());
+}
+
+const void* SoftwareFramebuffer::GetCurrentFramePixels() const {
+  DCHECK(framebuffer_holder_);
+  return framebuffer_holder_->GetPixels();
+}
+
+void SoftwareFramebuffer::SwapToNewFrame(
+    uint32 output_surface_id,
+    const cc::SoftwareFrameData* frame_data,
+    float frame_scale_factor) {
+  const gfx::Size& frame_size = frame_data->size;
+  const size_t size_in_bytes = 4 * frame_size.GetArea();
+
+#ifdef OS_WIN
+  scoped_ptr<base::SharedMemory> shared_memory(
+      new base::SharedMemory(frame_data->handle, true,
+        render_widget_host_impl_->GetProcess()->GetHandle()));
+#else
+  scoped_ptr<base::SharedMemory> shared_memory(
+      new base::SharedMemory(frame_data->handle, true));
+#endif
+
+  if (!shared_memory->Map(size_in_bytes)) {
+    render_widget_host_impl_->GetProcess()->ReceivedBadMessage();
+    framebuffer_holder_ = NULL;
+    return;
+  }
+
+  scoped_refptr<MemoryHolder> holder(new MemoryHolder(
+      shared_memory.Pass(),
+      frame_size,
+      frame_scale_factor,
+      base::Bind(&SoftwareFramebuffer::ReleaseSoftwareFrame,
+          AsWeakPtr(),
+          output_surface_id,
+          frame_data->id)));
+  framebuffer_holder_.swap(holder);
+
+  FrameMemoryManager::GetInstance()->AddFrame(
+      this, !render_widget_host_impl_->is_hidden());
+}
+
+void SoftwareFramebuffer::SendSoftwareFrameAck(uint32 output_surface_id) {
+  unsigned software_frame_id = 0;
+  if (!released_software_frames_.empty()) {
+    unsigned released_output_surface_id =
+      released_software_frames_.back().output_surface_id;
+    if (released_output_surface_id == output_surface_id) {
+      software_frame_id = released_software_frames_.back().frame_id;
+      released_software_frames_.pop_back();
+    }
+  }
+
+  cc::CompositorFrameAck ack;
+  ack.last_software_frame_id = software_frame_id;
+  if (render_widget_host_impl_) {
+    RenderWidgetHostImpl::SendSwapCompositorFrameAck(

[piman, 2013/10/08 02:58:38]

I would really prefer if the message sending logic stayed in the
RenderWidgetHostViewAura, and SoftwareFramebuffer wouldn't skip it and talked to
the RWHImpl directly. You could easily have a
SendSoftwareFrameAck(software_frame_id, output_surface_id) on
SoftwareFramebufferClient, as well as a similar SendReclaimSoftwareFrames. You
can keep the frame tracking logic here.
This makes it a lot clearer in the RWHVAura/Mac what's going on, and has a clear
separation of responsibilites: the SoftwareFramebuffer manages frames coming in
and out, and manages memory with the FrameMemoryManager, the RWHV* take care of
feeding the software frame to the compositor, and talking to the renderer.
As it is with this CL, the latter is distributed in several files, and hard to
follow.

[ccameron, 2013/10/22 07:15:55]

I did essentially this in the new version. The callbacks ended up being
SoftwareFrameWasFreed and CurrentSoftwareFrameWasEvicted (the latter does some
extra cleanup for Aura, but not Mac).

+        render_widget_host_impl_->GetRoutingID(), output_surface_id,
+        render_widget_host_impl_->GetProcess()->GetID(), ack);
+  }
+  SendReclaimSoftwareFrames();
+}
+
+void SoftwareFramebuffer::SendReclaimSoftwareFrames() {
+  while (!released_software_frames_.empty()) {
+    cc::CompositorFrameAck ack;
+    ack.last_software_frame_id = released_software_frames_.back().frame_id;
+    if (render_widget_host_impl_) {
+      RenderWidgetHostImpl::SendReclaimCompositorResources(
+          render_widget_host_impl_->GetRoutingID(),
+          released_software_frames_.back().output_surface_id,
+          render_widget_host_impl_->GetProcess()->GetID(),
+          ack);
+    }
+    released_software_frames_.pop_back();
+  }
+}
+
+void SoftwareFramebuffer::ReleaseSoftwareFrame(
+    uint32 output_surface_id,
+    unsigned software_frame_id) {
+  SendReclaimSoftwareFrames();
+  released_software_frames_.push_back(
+      ReleasedFrameInfo(output_surface_id, software_frame_id));
+}
+
+void SoftwareFramebuffer::ReleaseCurrentFrame() {
+  DCHECK(framebuffer_holder_);
+
+  DiscardCurrentFrame();
+
+  if (client_)
+    client_->CurrentSoftwareFrameWasDiscarded();
+}
+
+}  // namespace content