1 // Copyright (c) 2012 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 WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
6 #define WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
8 #include "third_party/WebKit/public/platform/WebFloatPoint.h"
9 #include "third_party/WebKit/public/platform/WebFloatSize.h"
10 #include "third_party/WebKit/public/platform/WebGestureCurve.h"
11 #include "third_party/WebKit/public/platform/WebSize.h"
12 #include "webkit/child/webkit_child_export.h"
15 class WebGestureCurveTarget;
18 namespace webkit_glue {
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 WebKit::WebGestureCurve {
27 WEBKIT_CHILD_EXPORT static WebGestureCurve* Create(
28 const WebKit::WebFloatPoint& initial_velocity,
29 float p0, float p1, float p2,
30 const WebKit::WebSize& cumulativeScroll);
32 virtual bool apply(double monotonicTime,
33 WebKit::WebGestureCurveTarget*) OVERRIDE;
36 TouchFlingGestureCurve(const WebKit::WebFloatPoint& initial_velocity,
40 const WebKit::WebSize& cumulativeScroll);
41 virtual ~TouchFlingGestureCurve();
43 WebKit::WebFloatPoint displacement_ratio_;
44 WebKit::WebFloatSize cumulative_scroll_;
45 float coefficients_[3];
47 float curve_duration_;
48 float position_offset_;
50 DISALLOW_COPY_AND_ASSIGN(TouchFlingGestureCurve);
53 } // namespace webkit_glue
55 #endif // WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_