qt-everywhere-src-5.14.1/qtquickcontrols/src/controls/Private/qquickrangemodel_p_p.h

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#ifndef QQUICKRANGEMODEL_P_P_H
#define QQUICKRANGEMODEL_P_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt Components API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "qquickrangemodel_p.h"

QT_BEGIN_NAMESPACE

class QQuickRangeModel1Private
{
    Q_DECLARE_PUBLIC(QQuickRangeModel1)
public:
    QQuickRangeModel1Private(QQuickRangeModel1 *qq);
    virtual ~QQuickRangeModel1Private();

    void init();

    qreal posatmin, posatmax;
    qreal minimum, maximum, stepSize, pos, value;

    uint inverted : 1;

    QQuickRangeModel1 *q_ptr;
    bool isComplete;
    bool positionChanged;
    bool valueChanged;

    inline qreal effectivePosAtMin() const {
        return inverted ? posatmax : posatmin;
    }

    inline qreal effectivePosAtMax() const {
        return inverted ? posatmin : posatmax;
    }

    inline qreal equivalentPosition(qreal value) const {
        // Return absolute position from absolute value
        const qreal valueRange = maximum - minimum;
        if (valueRange == 0)
            return effectivePosAtMin();

        const qreal scale = (effectivePosAtMax() - effectivePosAtMin()) / valueRange;
        return (value - minimum) * scale + effectivePosAtMin();
    }

    inline qreal equivalentValue(qreal pos) const {
        // Return absolute value from absolute position
        const qreal posRange = effectivePosAtMax() - effectivePosAtMin();
        if (posRange == 0)
            return minimum;

        const qreal scale = (maximum - minimum) / posRange;
        // Avoid perverse rounding glitches when at an end:
        const qreal mid = (effectivePosAtMax() + effectivePosAtMin()) * 0.5;
        if (pos < mid)
            return (pos - effectivePosAtMin()) * scale + minimum;
        return maximum - scale * (effectivePosAtMax() - pos);
    }

    qreal publicPosition(qreal position) const;
    qreal publicValue(qreal value) const;
    void emitValueAndPositionIfChanged(const qreal oldValue, const qreal oldPosition);
};

QT_END_NAMESPACE

#endif // QQUICKRANGEMODEL_P_P_H