// 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 WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
#define WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_
#include "third_party/WebKit/public/platform/WebFloatPoint.h"
#include "third_party/WebKit/public/platform/WebFloatSize.h"
#include "third_party/WebKit/public/platform/WebGestureCurve.h"
#include "third_party/WebKit/public/platform/WebSize.h"
#include "webkit/child/webkit_child_export.h"
namespace blink {
class WebGestureCurveTarget;
}
namespace webkit_glue {
// Implementation of WebGestureCurve suitable for touch pad/screen-based
// fling scroll. Starts with a flat velocity profile based on 'velocity', which
// tails off to zero. Time is scaled to that duration of the fling is
// proportional to the initial velocity.
class TouchFlingGestureCurve : public blink::WebGestureCurve {
public:
WEBKIT_CHILD_EXPORT static WebGestureCurve* Create(
const blink::WebFloatPoint& initial_velocity,
float p0, float p1, float p2,
const blink::WebSize& cumulativeScroll);
virtual bool apply(double monotonicTime,
blink::WebGestureCurveTarget*) OVERRIDE;
private:
TouchFlingGestureCurve(const blink::WebFloatPoint& initial_velocity,
float p0,
float p1,
float p2,
const blink::WebSize& cumulativeScroll);
virtual ~TouchFlingGestureCurve();
blink::WebFloatPoint displacement_ratio_;
blink::WebFloatSize cumulative_scroll_;
float coefficients_[3];
float time_offset_;
float curve_duration_;
float position_offset_;
DISALLOW_COPY_AND_ASSIGN(TouchFlingGestureCurve);
};
} // namespace webkit_glue
#endif // WEBKIT_CHILD_TOUCH_FLING_GESTURE_CURVE_H_