1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef CONTENT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
6 #define CONTENT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
8 #include "content/common/content_export.h"
9 #include "third_party/WebKit/public/platform/WebFloatPoint.h"
10 #include "third_party/WebKit/public/platform/WebFloatSize.h"
11 #include "third_party/WebKit/public/platform/WebGestureCurve.h"
12 #include "third_party/WebKit/public/platform/WebSize.h"
15 class WebGestureCurveTarget;
20 // Implementation of WebGestureCurve suitable for touch pad/screen-based
21 // fling scroll. Starts with a flat velocity profile based on 'velocity', which
22 // tails off to zero. Time is scaled to that duration of the fling is
23 // proportional to the initial velocity.
24 class TouchFlingGestureCurve : public blink::WebGestureCurve {
27 static CONTENT_EXPORT WebGestureCurve* Create(
28 const blink::WebFloatPoint& initial_velocity,
29 const blink::WebSize& cumulativeScroll);
31 virtual bool apply(double monotonicTime,
32 blink::WebGestureCurveTarget*) OVERRIDE;
35 TouchFlingGestureCurve(const blink::WebFloatPoint& initial_velocity,
36 const blink::WebSize& cumulativeScroll);
37 virtual ~TouchFlingGestureCurve();
39 blink::WebFloatPoint displacement_ratio_;
40 blink::WebFloatSize cumulative_scroll_;
42 float curve_duration_;
43 float position_offset_;
45 DISALLOW_COPY_AND_ASSIGN(TouchFlingGestureCurve);
48 } // namespace content
50 #endif // CONTENT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_