Android Webview IPC-based sync compositing

content/renderer/android/synchronous_compositor_proxy.h

+// Copyright 2015 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.
+
+#ifndef CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_PROXY_H_
+#define CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_PROXY_H_
+
+#include "base/macros.h"
+#include "content/common/input/input_event_ack_state.h"
+#include "content/renderer/android/synchronous_compositor_external_begin_frame_source.h"
+#include "content/renderer/android/synchronous_compositor_output_surface.h"
+#include "content/renderer/input/input_handler_manager_client.h"
+#include "content/renderer/input/synchronous_input_handler_proxy.h"
+#include "ui/gfx/geometry/scroll_offset.h"
+#include "ui/gfx/geometry/size_f.h"
+
+namespace IPC {
+class Message;
+class Sender;
+}  // namespace IPC
+
+namespace blink {
+class WebInputEvent;
+}

[dcheng, 2015/11/04 09:47:41]

Nit: // namespace blink for consistency

[boliu, 2015/11/04 16:52:05]

Done.

+
+namespace cc {
+class CompositorFrame;
+}  // namespace cc
+
+namespace content {
+
+class SynchronousCompositorOutputSurface;
+struct SyncCompositorCommonBrowserParams;
+struct SyncCompositorCommonRendererParams;
+struct SyncCompositorDemandDrawHwParams;
+
+class SynchronousCompositorProxy
+    : public SynchronousInputHandler,
+      public SynchronousCompositorExternalBeginFrameSourceClient,
+      public SynchronousCompositorOutputSurfaceClient {
+ public:
+  SynchronousCompositorProxy(
+      int routing_id,
+      IPC::Sender* sender,
+      SynchronousCompositorOutputSurface* output_surface,
+      SynchronousCompositorExternalBeginFrameSource* begin_frame_source,
+      SynchronousInputHandlerProxy* input_handler_proxy,
+      InputHandlerManagerClient::Handler* handler);
+  ~SynchronousCompositorProxy() override;
+
+  // SynchronousInputHandler overrides.
+  void SetNeedsSynchronousAnimateInput() override;
+  void UpdateRootLayerState(const gfx::ScrollOffset& total_scroll_offset,
+                            const gfx::ScrollOffset& max_scroll_offset,
+                            const gfx::SizeF& scrollable_size,
+                            float page_scale_factor,
+                            float min_page_scale_factor,
+                            float max_page_scale_factor) override;
+
+  // SynchronousCompositorExternalBeginFrameSourceClient overrides.
+  void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
+
+  // SynchronousCompositorOutputSurfaceClient overrides.
+  void Invalidate() override;
+
+  void OnMessageReceived(const IPC::Message& message);
+  bool Send(IPC::Message* message);
+
+ private:
+  void ProcessCommonParams(
+      const SyncCompositorCommonBrowserParams& common_params);
+  void ConstructCommonParams(SyncCompositorCommonRendererParams* params);
+
+  // IPC handlers.
+  void HandleInputEvent(
+      const SyncCompositorCommonBrowserParams& common_params,
+      const blink::WebInputEvent* event,
+      SyncCompositorCommonRendererParams* common_renderer_params,
+      InputEventAckState* ack);
+  void BeginFrame(const SyncCompositorCommonBrowserParams& common_params,
+                  const cc::BeginFrameArgs& args,
+                  SyncCompositorCommonRendererParams* common_renderer_params);
+  void OnComputeScroll(
+      const SyncCompositorCommonBrowserParams& common_params,
+      base::TimeTicks animation_time,
+      SyncCompositorCommonRendererParams* common_renderer_params);
+  void DemandDrawHw(const SyncCompositorCommonBrowserParams& common_params,
+                    const SyncCompositorDemandDrawHwParams& params,
+                    SyncCompositorCommonRendererParams* common_renderer_params,
+                    cc::CompositorFrame* frame);
+
+  void DidActivatePendingTree();
+  void DeliverMessages();
+  void SendAsyncRendererStateIfNeeded();
+
+  const int routing_id_;
+  IPC::Sender* const sender_;
+  SynchronousCompositorOutputSurface* const output_surface_;
+  SynchronousCompositorExternalBeginFrameSource* const begin_frame_source_;
+  SynchronousInputHandlerProxy* const input_handler_proxy_;
+  InputHandlerManagerClient::Handler* const input_handler_;
+  bool inside_receive_;  // TODO(boliu): versioning

[dcheng, 2015/11/04 09:47:41]

Not sure I understand this comment.

[boliu, 2015/11/04 16:52:05]

Just removed this comment.

I think this was a TODO for adding versioning parameter, since a synchronous
reply is sent back when inside_receive_ is flipped from true to false. Hmm,
depending on the message, maybe it's better to send it along with the
synchronous reply. That's an optimization which can come later.

+
+  // From browser.
+  size_t bytes_limit_;
+
+  unsigned version_;
+  gfx::ScrollOffset total_scroll_offset_;  // Modified by both.
+  gfx::ScrollOffset max_scroll_offset_;
+  gfx::SizeF scrollable_size_;
+  float page_scale_factor_;
+  float min_page_scale_factor_;
+  float max_page_scale_factor_;
+  bool need_animate_scroll_;
+  bool need_invalidate_;
+  bool need_begin_frame_;
+  bool did_activate_pending_tree_;
+
+  DISALLOW_COPY_AND_ASSIGN(SynchronousCompositorProxy);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_PROXY_H_