qwt_plot_rescaler.h

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/******************************************************************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/

#ifndef QWT_PLOT_RESCALER_H
#define QWT_PLOT_RESCALER_H

#include "qwt_global.h"
#include "qwt_plot.h"

#include <qobject.h>

class QwtPlot;
class QwtInterval;
class QResizeEvent;

class QWT_EXPORT QwtPlotRescaler : public QObject
{
    Q_OBJECT

  public:
    enum RescalePolicy
    {
        Fixed,

        Expanding,

        Fitting
    };

    enum ExpandingDirection
    {
        ExpandUp,

        ExpandDown,

        ExpandBoth
    };

    explicit QwtPlotRescaler( QWidget* canvas,
        QwtAxisId referenceAxis = QwtAxis::XBottom,
        RescalePolicy = Expanding );

    virtual ~QwtPlotRescaler();

    void setEnabled( bool );
    bool isEnabled() const;

    void setRescalePolicy( RescalePolicy );
    RescalePolicy rescalePolicy() const;

    void setExpandingDirection( ExpandingDirection );
    void setExpandingDirection( QwtAxisId, ExpandingDirection );
    ExpandingDirection expandingDirection( QwtAxisId ) const;

    void setReferenceAxis( QwtAxisId );
    QwtAxisId referenceAxis() const;

    void setAspectRatio( double ratio );
    void setAspectRatio( QwtAxisId, double ratio );
    double aspectRatio( QwtAxisId ) const;

    void setIntervalHint( QwtAxisId, const QwtInterval& );
    QwtInterval intervalHint( QwtAxisId ) const;

    QWidget* canvas();
    const QWidget* canvas() const;

    QwtPlot* plot();
    const QwtPlot* plot() const;

    virtual bool eventFilter( QObject*, QEvent* ) QWT_OVERRIDE;

    void rescale() const;

  protected:
    virtual void canvasResizeEvent( QResizeEvent* );

    virtual void rescale( const QSize& oldSize, const QSize& newSize ) const;
    virtual QwtInterval expandScale(
        QwtAxisId, const QSize& oldSize, const QSize& newSize ) const;

    virtual QwtInterval syncScale(
        QwtAxisId, const QwtInterval& reference, const QSize& size ) const;

    virtual void updateScales(
        QwtInterval intervals[QwtAxis::AxisPositions] ) const;

    Qt::Orientation orientation( QwtAxisId ) const;
    QwtInterval interval( QwtAxisId ) const;
    QwtInterval expandInterval( const QwtInterval&,
        double width, ExpandingDirection ) const;

  private:
    double pixelDist( QwtAxisId, const QSize& ) const;

    class AxisData;
    class PrivateData;
    PrivateData* m_data;
};

#endif