qwt_plot.h

#pragma once

#include "qwt_text.h"
#include "qwt_plot_dict.h"
#include "qwt_scale_map.h"
#include "qwt_interval.h"
#include <qframe.h>

class QwtPlotLayout;
class QwtLegend;
class QwtScaleWidget;
class QwtScaleEngine;
class QwtScaleDiv;
class QwtScaleDraw;
class QwtTextLabel;
class QwtPlotCanvas;

/*!
  \brief A 2-D plotting widget

  QwtPlot is a widget for plotting two-dimensional graphs.
  An unlimited number of plot items can be displayed on
  its canvas. Plot items might be curves (QwtPlotCurve), markers
  (QwtPlotMarker), the grid (QwtPlotGrid), or anything else derived
  from QwtPlotItem.
  A plot can have up to four axes, with each plot item attached to an x- and
  a y axis. The scales at the axes can be explicitely set (QwtScaleDiv), or
  are calculated from the plot items, using algorithms (QwtScaleEngine) which
  can be configured separately for each axis.

  \image html plot.png

  \par Example
  The following example shows (schematically) the most simple
  way to use QwtPlot. By default, only the left and bottom axes are
  visible and their scales are computed automatically.
  \verbatim
#include <qwt_plot.h>
#include <qwt_plot_curve.h>

QwtPlot *myPlot = new QwtPlot("Two Curves", parent);

// add curves
QwtPlotCurve *curve1 = new QwtPlotCurve("Curve 1");
QwtPlotCurve *curve2 = new QwtPlotCurve("Curve 2");

// copy the data into the curves
curve1->setData(...);
curve2->setData(...);

curve1->attach(myPlot);
curve2->attach(myPlot);

// finally, refresh the plot
myPlot->replot();
\endverbatim
*/

class QwtPlot: public QFrame, public QwtPlotDict
{
    Q_OBJECT

public:
    //! \brief Axis index
    enum Axis
    {
        //! Y axis left of the canvas
        yLeft,

        //! Y axis right of the canvas
        yRight,

        //! X axis below the canvas
        xBottom,

        //! X axis above the canvas
        xTop,

        //! Number of axes
        axisCnt
    };

    /*!
        Position of the legend, relative to the canvas.

        \sa insertLegend()
        \note In case of ExternalLegend, the legend is not
              handled by QwtPlotRenderer
     */
    enum LegendPosition
    {
        //! The legend will be left from the QwtPlot::yLeft axis.
        LeftLegend,

        //! The legend will be right from the QwtPlot::yRight axis.
        RightLegend,

        //! The legend will be below QwtPlot::xBottom axis.
        BottomLegend,

        //! The legend will be between QwtPlot::xTop axis and the title.
        TopLegend,

        /*!
          External means that only the content of the legend
          will be handled by QwtPlot, but not its geometry.
          This type can be used to have a legend in an 
          external window ( or on the canvas ).
         */
        ExternalLegend
    };

    explicit QwtPlot( QWidget * = NULL );
    explicit QwtPlot( const QwtText &title, QWidget *p = NULL );

    virtual ~QwtPlot();

    // Layout

    QwtPlotLayout *plotLayout();
    const QwtPlotLayout *plotLayout() const;

    // Title

    void setTitle( const QString & );
    void setTitle( const QwtText &t );
    QwtText title() const;

    QwtTextLabel *titleLabel();
    const QwtTextLabel *titleLabel() const;

    // Canvas

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

    void setCanvasBackground( const QBrush & );
    QBrush canvasBackground() const;

    void setCanvasLineWidth( int w );
    int canvasLineWidth() const;

    virtual QwtScaleMap canvasMap( int axisId ) const;

    double invTransform( int axisId, int pos ) const;
    double transform( int axisId, double value ) const;

    // Axes

    QwtScaleEngine *axisScaleEngine( int axisId );
    const QwtScaleEngine *axisScaleEngine( int axisId ) const;
    void setAxisScaleEngine( int axisId, QwtScaleEngine * );

    void enableAxis( int axisId, bool tf = true );
    bool axisEnabled( int axisId ) const;

    void setAxisFont( int axisId, const QFont &f );
    QFont axisFont( int axisId ) const;

    void setAxisScale( int axisId, double min, double max, double step = 0 );
    void setAxisScaleDiv( int axisId, const QwtScaleDiv & );
    void setAxisScaleDraw( int axisId, QwtScaleDraw * );

    double axisStepSize( int axisId ) const;
    QwtInterval axisInterval( int axisId ) const;

    const QwtScaleDiv *axisScaleDiv( int axisId ) const;
    QwtScaleDiv *axisScaleDiv( int axisId );

    const QwtScaleDraw *axisScaleDraw( int axisId ) const;
    QwtScaleDraw *axisScaleDraw( int axisId );

    const QwtScaleWidget *axisWidget( int axisId ) const;
    QwtScaleWidget *axisWidget( int axisId );

    void setAxisTitle( int axisId, const QString & );
    void setAxisTitle( int axisId, const QwtText & );
    QwtText axisTitle( int axisId ) const;

    void setAxisMaxMinor( int axisId, int maxMinor );
    int axisMaxMinor( int axisId ) const;

    void setAxisMaxMajor( int axisId, int maxMajor );
    int axisMaxMajor( int axisId ) const;

    // Legend

    void insertLegend( QwtLegend *, LegendPosition = QwtPlot::RightLegend,
        double ratio = -1.0 );

    QwtLegend *legend();
    const QwtLegend *legend() const;

    // Misc

    virtual QSize sizeHint() const;
    virtual QSize minimumSizeHint() const;

    virtual void updateLayout();
    virtual void drawCanvas( QPainter * );

    void updateAxes();

    virtual bool event( QEvent * );

    virtual void drawItems( QPainter *, const QRectF &,
        const QwtScaleMap maps[axisCnt] ) const;

public Q_SLOTS:
    virtual void replot();

protected:
    static bool axisValid( int axisId );

    virtual void updateTabOrder();

    virtual void resizeEvent( QResizeEvent *e );

private:
    void initAxesData();
    void deleteAxesData();
    void updateScaleDiv();

    void initPlot( const QwtText &title );

    class AxisData;
    AxisData *d_axisData[axisCnt];

    class PrivateData;
    PrivateData *d_data;
};