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// Copyright (C) 2018 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
// Qt-Security score:significant reason:default
#include <QtLottie/private/qbeziereasing_p.h>
QT_BEGIN_NAMESPACE
void QBezierEasing::addCubicBezierSegment(const QPointF &c1, const QPointF &c2, const QPointF &endPoint)
{
mBezier = QBezier::fromPoints(QPointF(0.0, 0.0), c1, c2, endPoint);
}
qreal QBezierEasing::valueForProgress(qreal progress) const
{
return mBezier.pointAt(tForX(progress)).y();
}
qreal QBezierEasing::tForX(qreal x) const
{
if (x <= 0.0)
return 0.0;
else if (x >= 1.0)
return 1.0;
qreal t0 = 0.0;
qreal t1 = 1.0;
for (int i = 0; i < 10; i++) { // 10 iterations gives error smaller than 0.001
qreal t = qreal(0.5) * (t0 + t1);
qreal a, b, c, d;
QBezier::coefficients(t, a, b, c, d);
qreal xt = a * mBezier.x1 + b * mBezier.x2 + c * mBezier.x3 + d * mBezier.x4;
if (xt < x)
t0 = t;
else
t1 = t;
}
return t0;
}
QT_END_NAMESPACE