Adding Gesture Recognition to RenderWidgetHostViewWin (web client)

ui/base/gestures/gesture_types.h

 // Copyright (c) 2012 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 UI_BASE_GESTURES_GESTURE_TYPES_H_
 #define UI_BASE_GESTURES_GESTURE_TYPES_H_
 #pragma once
 
 #include "base/time.h"
 #include "ui/base/events.h"
@@ skipping 22 matching lines @@
 };
 
 // An abstract type to represent gesture-events.
 class UI_EXPORT GestureEvent {
  public:
   virtual ~GestureEvent() {}
 
   // A gesture event can have multiple touches. This function should return the
   // lowest ID of the touches in this gesture.
   virtual int GetLowestTouchId() const = 0;
+
+  // A helper function used in several (all) derived classes.
+  // Returns lowest set bit, or -1 if no bits are set.
+  static int LowestBit(unsigned int bitfield) {
+    int i = -1;
+    // Find the index of the least significant 1 bit
+    while (bitfield && (!((1 << ++i) & bitfield)));
+    return i;
+  }
 };
 
 // An abstract type for consumers of gesture-events created by the
 // gesture-recognizer.
 class UI_EXPORT GestureConsumer {
  public:
   GestureConsumer()
       : ignores_events_(false) {
   }
 
@@ skipping 16 matching lines @@
 class UI_EXPORT GestureEventHelper {
  public:
   virtual ~GestureEventHelper() {
   }
 
   // |flags| is ui::EventFlags. The meaning of |param_first| and |param_second|
   // depends on the specific gesture type (|type|).
   virtual GestureEvent* CreateGestureEvent(EventType type,
                                            const gfx::Point& location,
                                            int flags,
-                                           const base::Time time,
+                                           base::Time time,
                                            float param_first,
                                            float param_second,
                                            unsigned int touch_id_bitfield) = 0;
 
   virtual TouchEvent* CreateTouchEvent(EventType type,
                                        const gfx::Point& location,
                                        int touch_id,
                                        base::TimeDelta time_stamp) = 0;
 
   virtual bool DispatchLongPressGestureEvent(GestureEvent* event) = 0;
   virtual bool DispatchCancelTouchEvent(TouchEvent* event) = 0;
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_GESTURES_GESTURE_TYPES_H_