MuseScore/src/engraving/libmscore/easeInOut.h
2021-08-26 13:16:41 +02:00

68 lines
2.3 KiB
C++

/*
* SPDX-License-Identifier: GPL-3.0-only
* MuseScore-CLA-applies
*
* MuseScore
* Music Composition & Notation
*
* Copyright (C) 2021 MuseScore BVBA and others
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 3 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef __EASEINOUT_H__
#define __EASEINOUT_H__
#include <QtGlobal>
#include "infrastructure/draw/geometry.h"
namespace Ms {
//---------------------------------------------------------
// @@ EaseInOut
/// \brief Specialized transfer curve using an underlying Bezier curve.
///
/// The second and third control points of the Bezier curve are moveable
/// along the x axis according to two parameters 'EaseIn' and 'EaseOut',
/// which results in a transfer curve that goes from a straight line to an S
/// shaped curve.
//---------------------------------------------------------
class EaseInOut final
{
qreal _easeIn;
qreal _easeOut;
public:
EaseInOut()
: _easeIn(0.0), _easeOut(1.0) {}
EaseInOut(qreal easeIn, qreal easeOut)
: _easeIn(easeIn), _easeOut(easeOut) {}
void SetEases(qreal easeIn, qreal easeOut) { _easeIn = easeIn; _easeOut = easeOut; }
qreal EvalX(const qreal t) const
{
qreal tCompl = 1.0 - t;
return (3.0 * _easeIn * tCompl * tCompl + (3.0 - 3.0 * _easeOut * tCompl - 2.0 * t) * t) * t;
}
qreal EvalY(const qreal t) const { return -(t * t) * (2.0 * t - 3.0); }
mu::PointF Eval(const qreal t) const { return { EvalX(t), EvalY(t) }; }
qreal tFromX(const qreal x) const;
qreal tFromY(const qreal y) const;
qreal YfromX(const qreal x) const { return EvalY(tFromX(x)); }
qreal XfromY(const qreal y) const { return EvalX(tFromY(y)); }
void timeList(const int nbNotes, const int duration, QList<int>* times) const;
};
} // namespace Ms
#endif