qwt_plot_rescaler.h

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * 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 1

#include "qwt_global.h"
#include "qwt_interval.h"
#include "qwt_plot.h"
#include <qobject.h>

class QwtPlotCanvas;
class QwtPlot;
class QResizeEvent;

class QWT_EXPORT QwtPlotRescaler: public QObject
{
public:
    enum RescalePolicy
    {
        Fixed,

        Expanding,

        Fitting
    };

    enum ExpandingDirection
    {
        ExpandUp,

        ExpandDown,

        ExpandBoth
    };

    explicit QwtPlotRescaler( QwtPlotCanvas *,
        int referenceAxis = QwtPlot::xBottom,
        RescalePolicy = Expanding );

    virtual ~QwtPlotRescaler();

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

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

    void setExpandingDirection( ExpandingDirection );
    void setExpandingDirection( int axis, ExpandingDirection );
    ExpandingDirection expandingDirection( int axis ) const;

    void setReferenceAxis( int axis );
    int referenceAxis() const;

    void setAspectRatio( double ratio );
    void setAspectRatio( int axis, double ratio );
    double aspectRatio( int axis ) const;

    void setIntervalHint( int axis, const QwtInterval& );
    QwtInterval intervalHint( int axis ) const;

    QwtPlotCanvas *canvas();
    const QwtPlotCanvas *canvas() const;

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

    virtual bool eventFilter( QObject *, QEvent * );

    void rescale() const;

protected:
    virtual void canvasResizeEvent( QResizeEvent * );

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

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

    virtual void updateScales(
        QwtInterval intervals[QwtPlot::axisCnt] ) const;

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

private:
    double pixelDist( int axis, const QSize & ) const;

    class AxisData;
    class PrivateData;
    PrivateData *d_data;
};

#endif