blimp: Add support for input handling

blimp/client/input/blimp_input_manager.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 BLIMP_CLIENT_INPUT_BLIMP_INPUT_MANAGER_H_
+#define BLIMP_CLIENT_INPUT_BLIMP_INPUT_MANAGER_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/single_thread_task_runner.h"
+#include "third_party/WebKit/public/web/WebInputEvent.h"
+#include "ui/events/blink/input_handler_proxy.h"
+#include "ui/events/blink/input_handler_proxy_client.h"
+#include "ui/events/gesture_detection/filtered_gesture_provider.h"
+#include "ui/events/gesture_detection/motion_event.h"
+
+namespace blimp {
+
+class BlimpInputManagerClient {
+ public:
+  virtual void SendWebInputEvent(
+      const blink::WebInputEvent& input_event) = 0;
+};
+
+// The BlimpInputManager handles input events for a specific render widget. The
+// class processes ui::events to generate web input events which are forwarded
+// to the compositor to be handled on the compositor thread. If the event can
+// not be handled locally by the compositor, it is given to the
+// BlimpInputManagerClient to be sent to the engine.
+class BlimpInputManager : public ui::InputHandlerProxyClient,
+                          public ui::GestureProviderClient {
+ public:
+  static scoped_ptr<BlimpInputManager> Create(
+      BlimpInputManagerClient* client,
+      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner,
+      const base::WeakPtr<cc::InputHandler>& input_handler);
+
+  ~BlimpInputManager();
+
+  // Called to process a ui::MotionEvent. Returns true if the event was
+  // successfully processed.
+  bool OnTouchEvent(const ui::MotionEvent& motion_event);
+
+ private:
+  BlimpInputManager(
+      BlimpInputManagerClient* client,
+      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner,
+      const base::WeakPtr<cc::InputHandler>& input_handler);
+
+
+  // InputHandlerProxyClient implementation. Called on the compositor thread.
+  void WillShutdown() override;
+  void TransferActiveWheelFlingAnimation(
+      const blink::WebActiveWheelFlingParameters& params) override;
+  blink::WebGestureCurve* CreateFlingAnimationCurve(
+      blink::WebGestureDevice device_source,
+      const blink::WebFloatPoint& velocity,
+      const blink::WebSize& cumulative_scroll) override;
+  void DidOverscroll(const gfx::Vector2dF& accumulated_overscroll,
+                     const gfx::Vector2dF& latest_overscroll_delta,
+                     const gfx::Vector2dF& current_fling_velocity,
+                     const gfx::PointF& causal_event_viewport_point) override;
+  void DidStopFlinging() override;
+  void DidAnimateForInput() override;
+
+  // ui::GestureProviderClient implementation. Called on main thread.
+  void OnGestureEvent(const ui::GestureEventData& gesture) override;
+
+  void CreateInputHandlerProxyOnCompositorThread(
+      const base::WeakPtr<cc::InputHandler>& input_handler);
+  void HandleWebInputEventOnCompositorThread(
+      const blink::WebInputEvent& input_event);
+  void SendWebInputEvent(const blink::WebInputEvent& input_event);
+
+  bool IsMainThread() const;
+  bool IsCompositorThread() const;
+
+  BlimpInputManagerClient* client_;
+
+  scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner_;
+
+  ui::FilteredGestureProvider gesture_provider_;
+
+  scoped_ptr<ui::InputHandlerProxy> input_handler_proxy_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlimpInputManager);
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_INPUT_BLIMP_INPUT_MANAGER_H_