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/*

| *property* | *Used for type* |

| period     | QEasingCurve::{In,Out,InOut,OutIn}Elastic |

| amplitude  | QEasingCurve::{In,Out,InOut,OutIn}Bounce, QEasingCurve::{In,Out,InOut,OutIn}Elastic |

| overshoot  | QEasingCurve::{In,Out,InOut,OutIn}Back   |

*/

/*!

    \class QEasingCurve

    \since 4.6

    \ingroup animation

    \brief The QEasingCurve class provides easing curves for controlling animation.

    Easing curves describe a function that controls how the speed of the interpolation

    between 0 and 1 should be. Easing curves allow transitions from

    one value to another to appear more natural than a simple constant speed would allow.

    The QEasingCurve class is usually used in conjunction with the QVariantAnimation and

    QPropertyAnimation classes but can be used on its own. It is usually used to accelerate

    the interpolation from zero velocity (ease in) or decelerate to zero velocity (ease out).

    Ease in and ease out can also be combined in the same easing curve.

    To calculate the speed of the interpolation, the easing curve provides the function

    valueForProgress(), where the \a progress argument specifies the progress of the

    interpolation: 0 is the start value of the interpolation, 1 is the end value of the

    interpolation. The returned value is the effective progress of the interpolation.

    If the returned value is the same as the input value for all input values the easing

    curve is a linear curve. This is the default behaviour.

    For example,

    \code

    QEasingCurve easing(QEasingCurve::InOutQuad);

    for(qreal t = 0.0; t < 1.0; t+=0.1)

        qWarning() << "Effective progress" << t << " is

                   << easing.valueForProgress(t);

    \endcode

    will print the effective progress of the interpolation between 0 and 1.

    When using a QPropertyAnimation, the associated easing curve will be used to control the

    progress of the interpolation between startValue and endValue:

    \code

    QPropertyAnimation animation;

    animation.setStartValue(0);

    animation.setEndValue(1000);

    animation.setDuration(1000);

    animation.setEasingCurve(QEasingCurve::InOutQuad);

    \endcode

 */

/*!

    \enum QEasingCurve::Type

    The type of easing curve.

    \value Linear       \inlineimage qeasingcurve-linear.png

                        \br

                        Easing curve for a linear (t) function:

                        velocity is constant.

    \value InQuad       \inlineimage qeasingcurve-inquad.png

                        \br

                        Easing curve for a quadratic (t^2) function:

                        accelerating from zero velocity.

    \value OutQuad      \inlineimage qeasingcurve-outquad.png

                        \br

                        Easing curve for a quadratic (t^2) function:

                        decelerating to zero velocity.

    \value InOutQuad    \inlineimage qeasingcurve-inoutquad.png

                        \br

                        Easing curve for a quadratic (t^2) function:

                        acceleration until halfway, then deceleration.

    \value OutInQuad    \inlineimage qeasingcurve-outinquad.png

                        \br

                        Easing curve for a quadratic (t^2) function:

                        deceleration until halfway, then acceleration.

    \value InCubic      \inlineimage qeasingcurve-incubic.png

                        \br

                        Easing curve for a cubic (t^3) function:

                        accelerating from zero velocity.

    \value OutCubic     \inlineimage qeasingcurve-outcubic.png

                        \br

                        Easing curve for a cubic (t^3) function:

                        decelerating to zero velocity.

    \value InOutCubic   \inlineimage qeasingcurve-inoutcubic.png

                        \br

                        Easing curve for a cubic (t^3) function:

                        acceleration until halfway, then deceleration.

    \value OutInCubic   \inlineimage qeasingcurve-outincubic.png

                        \br

                        Easing curve for a cubic (t^3) function:

                        deceleration until halfway, then acceleration.

    \value InQuart      \inlineimage qeasingcurve-inquart.png

                        \br

                        Easing curve for a quartic (t^4) function:

                        accelerating from zero velocity.

    \value OutQuart     \inlineimage qeasingcurve-outquart.png

                        \br

                        decelerating to zero velocity.

    \value InOutQuart   \inlineimage qeasingcurve-inoutquart.png

                        \br

                        acceleration until halfway, then deceleration.

    \value OutInQuart   \inlineimage qeasingcurve-outinquart.png

                        \br

                        deceleration until halfway, then acceleration.

    \value InQuint      \inlineimage qeasingcurve-inquint.png

                        \br

                        Easing curve for a quintic (t^5) easing

                        in: accelerating from zero velocity.

    \value OutQuint     \inlineimage qeasingcurve-outquint.png

                        \br

                        decelerating to zero velocity.

    \value InOutQuint   \inlineimage qeasingcurve-inoutquint.png

                        \br

                        acceleration until halfway, then deceleration.

    \value OutInQuint   \inlineimage qeasingcurve-outinquint.png

                        \br

                        deceleration until halfway, then acceleration.

    \value InSine       \inlineimage qeasingcurve-insine.png

                        \br

                        Easing curve for a sinusoidal (sin(t)) function:

                        accelerating from zero velocity.

    \value OutSine      \inlineimage qeasingcurve-outsine.png

                        \br

                        Easing curve for a sinusoidal (sin(t)) function:

                        decelerating from zero velocity.

    \value InOutSine    \inlineimage qeasingcurve-inoutsine.png

                        \br

                        Easing curve for a sinusoidal (sin(t)) function:

                        acceleration until halfway, then deceleration.

    \value OutInSine    \inlineimage qeasingcurve-outinsine.png

                        \br

                        Easing curve for a sinusoidal (sin(t)) function:

                        deceleration until halfway, then acceleration.

    \value InExpo       \inlineimage qeasingcurve-inexpo.png

                        \br

                        Easing curve for an exponential (2^t) function:

                        accelerating from zero velocity.

    \value OutExpo      \inlineimage qeasingcurve-outexpo.png

                        \br

                        Easing curve for an exponential (2^t) function:

                        decelerating from zero velocity.

    \value InOutExpo    \inlineimage qeasingcurve-inoutexpo.png

                        \br

                        Easing curve for an exponential (2^t) function:

                        acceleration until halfway, then deceleration.

    \value OutInExpo    \inlineimage qeasingcurve-outinexpo.png

                        \br

                        Easing curve for an exponential (2^t) function:

                        deceleration until halfway, then acceleration.

    \value InCirc       \inlineimage qeasingcurve-incirc.png

                        \br

                        Easing curve for a circular (sqrt(1-t^2)) function:

                        accelerating from zero velocity.

    \value OutCirc      \inlineimage qeasingcurve-outcirc.png

                        \br

                        Easing curve for a circular (sqrt(1-t^2)) function:

                        decelerating from zero velocity.

    \value InOutCirc    \inlineimage qeasingcurve-inoutcirc.png

                        \br

                        Easing curve for a circular (sqrt(1-t^2)) function:

                        acceleration until halfway, then deceleration.

    \value OutInCirc    \inlineimage qeasingcurve-outincirc.png

                        \br

                        Easing curve for a circular (sqrt(1-t^2)) function:

                        deceleration until halfway, then acceleration.

    \value InElastic    \inlineimage qeasingcurve-inelastic.png

                        \br

                        Easing curve for an elastic

                        (exponentially decaying sine wave) function:

                        accelerating from zero velocity.  The peak amplitude

                        can be set with the \e amplitude parameter, and the

                        period of decay by the \e period parameter.

    \value OutElastic   \inlineimage qeasingcurve-outelastic.png

                        \br

                        Easing curve for an elastic

                        (exponentially decaying sine wave) function:

                        decelerating from zero velocity.  The peak amplitude

                        can be set with the \e amplitude parameter, and the

                        period of decay by the \e period parameter.

    \value InOutElastic \inlineimage qeasingcurve-inoutelastic.png

                        \br

                        Easing curve for an elastic

                        (exponentially decaying sine wave) function:

                        acceleration until halfway, then deceleration.

    \value OutInElastic \inlineimage qeasingcurve-outinelastic.png

                        \br

                        Easing curve for an elastic

                        (exponentially decaying sine wave) function:

                        deceleration until halfway, then acceleration.

    \value InBack       \inlineimage qeasingcurve-inback.png

                        \br

                        Easing curve for a back (overshooting

                        cubic function: (s+1)*t^3 - s*t^2) easing in:

                        accelerating from zero velocity.

    \value OutBack      \inlineimage qeasingcurve-outback.png

                        \br

                        Easing curve for a back (overshooting

                        cubic function: (s+1)*t^3 - s*t^2) easing out:

                        decelerating to zero velocity.

    \value InOutBack    \inlineimage qeasingcurve-inoutback.png

                        \br

                        Easing curve for a back (overshooting

                        cubic function: (s+1)*t^3 - s*t^2) easing in/out:

                        acceleration until halfway, then deceleration.

    \value OutInBack    \inlineimage qeasingcurve-outinback.png

                        \br

                        Easing curve for a back (overshooting

                        cubic easing: (s+1)*t^3 - s*t^2) easing out/in:

                        deceleration until halfway, then acceleration.

    \value InBounce     \inlineimage qeasingcurve-inbounce.png

                        \br

                        Easing curve for a bounce (exponentially

                        decaying parabolic bounce) function: accelerating

                        from zero velocity.

    \value OutBounce    \inlineimage qeasingcurve-outbounce.png

                        \br

                        Easing curve for a bounce (exponentially

                        decaying parabolic bounce) function: decelerating

                        from zero velocity.

    \value InOutBounce  \inlineimage qeasingcurve-inoutbounce.png

                        \br

                        Easing curve for a bounce (exponentially

                        decaying parabolic bounce) function easing in/out:

                        acceleration until halfway, then deceleration.

    \value OutInBounce  \inlineimage qeasingcurve-outinbounce.png

                        \br

                        Easing curve for a bounce (exponentially

                        decaying parabolic bounce) function easing out/in:

                        deceleration until halfway, then acceleration.

    \omitvalue InCurve

    \omitvalue OutCurve

    \omitvalue SineCurve

    \omitvalue CosineCurve

    \value Custom       This is returned if the user specified a custom curve type with

                        setCustomType(). Note that you cannot call setType() with this value,

                        but type() can return it.

    \omitvalue NCurveTypes

*/

/*!

    \typedef QEasingCurve::EasingFunction

    This is a typedef for a pointer to a function with the following

    signature:

    \snippet doc/src/snippets/code/src_corelib_tools_qeasingcurve.cpp 0

*/

#include "qeasingcurve.h"

#ifndef QT_NO_DEBUG_STREAM

#include <QtCore/qdebug.h>

#include <QtCore/qstring.h>

#endif

#ifndef QT_NO_DATASTREAM

#include <QtCore/qdatastream.h>

#endif

QT_BEGIN_NAMESPACE

static bool isConfigFunction(QEasingCurve::Type type)

{

    return type >= QEasingCurve::InElastic

            && type <= QEasingCurve::OutInBounce;

}

class QEasingCurveFunction

{

public:

    enum Type { In, Out, InOut, OutIn };

    QEasingCurveFunction(QEasingCurveFunction::Type type = In, qreal period = 0.3, qreal amplitude = 1.0,

        qreal overshoot = 1.70158f)

        : _t(type), _p(period), _a(amplitude), _o(overshoot)

    { }

    virtual ~QEasingCurveFunction() {}

    virtual qreal value(qreal t);

    virtual QEasingCurveFunction *copy() const;

    bool operator==(const QEasingCurveFunction& other);

    Type _t;

    qreal _p;

    qreal _a;

    qreal _o;

};

qreal QEasingCurveFunction::value(qreal t)

{

    return t;

}

QEasingCurveFunction *QEasingCurveFunction::copy() const

{

    return new QEasingCurveFunction(_t, _p, _a, _o);

}

bool QEasingCurveFunction::operator==(const QEasingCurveFunction& other)

{

    return _t == other._t &&

           _p == other._p &&

           _a == other._a &&

           _o == other._o;

}

QT_BEGIN_INCLUDE_NAMESPACE

#include "../../3rdparty/easing/easing.cpp"

QT_END_INCLUDE_NAMESPACE

class QEasingCurvePrivate

{

public:

    QEasingCurvePrivate()

        : type(QEasingCurve::Linear),

          config(0),

          func(&easeNone)

    { }

    ~QEasingCurvePrivate() { delete config; }

    void setType_helper(QEasingCurve::Type);

    QEasingCurve::Type type;

    QEasingCurveFunction *config;

    QEasingCurve::EasingFunction func;

};

struct ElasticEase : public QEasingCurveFunction

{

    ElasticEase(Type type)

        : QEasingCurveFunction(type, qreal(0.3), qreal(1.0))

    { }

    QEasingCurveFunction *copy() const

    {

        ElasticEase *rv = new ElasticEase(_t);

        rv->_p = _p;

        rv->_a = _a;

        return rv;

    }

    qreal value(qreal t)

    {

        qreal p = (_p < 0) ? 0.3f : _p;

        qreal a = (_a < 0) ? 1.0f : _a;

        switch(_t) {

        case In:

            return easeInElastic(t, a, p);

        case Out:

            return easeOutElastic(t, a, p);

        case InOut:

            return easeInOutElastic(t, a, p);

        case OutIn:

            return easeOutInElastic(t, a, p);

        default:

            return t;

        }

    }

};

struct BounceEase : public QEasingCurveFunction

{

    BounceEase(Type type)

        : QEasingCurveFunction(type, 0.3f, 1.0f)

    { }

    QEasingCurveFunction *copy() const

    {

        BounceEase *rv = new BounceEase(_t);

        rv->_a = _a;

        return rv;

    }

    qreal value(qreal t)

    {

        qreal a = (_a < 0) ? 1.0f : _a;

        switch(_t) {

        case In:

            return easeInBounce(t, a);

        case Out:

            return easeOutBounce(t, a);

        case InOut:

            return easeInOutBounce(t, a);

        case OutIn:

            return easeOutInBounce(t, a);

        default:

            return t;

        }

    }

};

struct BackEase : public QEasingCurveFunction

{

    BackEase(Type type)

        : QEasingCurveFunction(type, 0.3f, 1.0f, 1.70158f)

    { }

    QEasingCurveFunction *copy() const

    {

        BackEase *rv = new BackEase(_t);

        rv->_o = _o;

        return rv;

    }

    qreal value(qreal t)

    {

        qreal o = (_o < 0) ? 1.70158f : _o;

        switch(_t) {

        case In:

            return easeInBack(t, o);

        case Out:

            return easeOutBack(t, o);

        case InOut:

            return easeInOutBack(t, o);

        case OutIn:

            return easeOutInBack(t, o);

        default:

            return t;

        }

    }

};

static QEasingCurve::EasingFunction curveToFunc(QEasingCurve::Type curve)

{

    switch(curve) {

    case QEasingCurve::Linear:

        return &easeNone;

    case QEasingCurve::InQuad:

        return &easeInQuad;

    case QEasingCurve::OutQuad:

        return &easeOutQuad;

    case QEasingCurve::InOutQuad:

        return &easeInOutQuad;

    case QEasingCurve::OutInQuad:

        return &easeOutInQuad;

    case QEasingCurve::InCubic:

        return &easeInCubic;

    case QEasingCurve::OutCubic:

        return &easeOutCubic;

    case QEasingCurve::InOutCubic:

        return &easeInOutCubic;

    case QEasingCurve::OutInCubic:

        return &easeOutInCubic;

    case QEasingCurve::InQuart:

        return &easeInQuart;

    case QEasingCurve::OutQuart:

        return &easeOutQuart;

    case QEasingCurve::InOutQuart:

        return &easeInOutQuart;

    case QEasingCurve::OutInQuart:

        return &easeOutInQuart;

    case QEasingCurve::InQuint:

        return &easeInQuint;

    case QEasingCurve::OutQuint:

        return &easeOutQuint;

    case QEasingCurve::InOutQuint:

        return &easeInOutQuint;

    case QEasingCurve::OutInQuint:

        return &easeOutInQuint;

    case QEasingCurve::InSine:

        return &easeInSine;

    case QEasingCurve::OutSine:

        return &easeOutSine;

    case QEasingCurve::InOutSine:

        return &easeInOutSine;

    case QEasingCurve::OutInSine: