qwt_plot_histogram.h

/******************************************************************************
 * 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
 *
 * Modified by ChenZongYan in 2024 <czy.t@163.com>
 *   Summary of major modifications (see ChangeLog.md for full history):
 *   1. CMake build system & C++11 throughout.
 *   2. Core panner/ zoomer refactored:
 *        - QwtPanner → QwtCachePanner (pixmap-cache version)
 *        - New real-time QwtPlotPanner derived from QwtPicker.
 *   3. Zoomer supports multi-axis.
 *   4. Parasite-plot framework:
 *        - QwtFigure, QwtPlotParasiteLayout, QwtPlotTransparentCanvas,
 *        - QwtPlotScaleEventDispatcher, built-in pan/zoom on axis.
 *   5. New picker: QwtPlotSeriesDataPicker (works with date axis).
 *   6. Raster & color-map extensions:
 *        - QwtGridRasterData (2-D table + interpolation)
 *        - QwtLinearColorMap::stopColors(), stopPos() API rename.
 *   7. Bar-chart: expose pen/brush control.
 *   8. Amalgamated build: single QwtPlot.h / QwtPlot.cpp pair in src-amalgamate.
 *****************************************************************************/
 
#ifndef QWT_PLOT_HISTOGRAM_H
#define QWT_PLOT_HISTOGRAM_H
 
#include "qwt_global.h"
#include "qwt_plot_seriesitem.h"
 
class QwtColumnSymbol;
class QwtColumnRect;
class QColor;
class QPolygonF;
 
#if QT_VERSION < 0x060000
template< typename T > class QVector;
#endif
 
class QWT_EXPORT QwtPlotHistogram
    : public QwtPlotSeriesItem
    , public QwtSeriesStore< QwtIntervalSample >
{
  public:
    enum HistogramStyle
    {
        Outline,
 
        Columns,
 
        Lines,
 
        UserStyle = 100
    };
 
    explicit QwtPlotHistogram( const QString& title = QString() );
    explicit QwtPlotHistogram( const QwtText& title );
    virtual ~QwtPlotHistogram();
 
    virtual int rtti() const QWT_OVERRIDE;
 
    void setPen( const QColor&,
        qreal width = 0.0, Qt::PenStyle = Qt::SolidLine );
 
    void setPen( const QPen& );
    const QPen& pen() const;
 
    void setBrush( const QBrush& );
    const QBrush& brush() const;
 
    void setSamples( const QVector< QwtIntervalSample >& );
    void setSamples( QwtSeriesData< QwtIntervalSample >* );
 
    void setBaseline( double );
    double baseline() const;
 
    void setStyle( HistogramStyle style );
    HistogramStyle style() const;
 
    void setSymbol( const QwtColumnSymbol* );
    const QwtColumnSymbol* symbol() const;
 
    virtual void drawSeries( QPainter*,
        const QwtScaleMap& xMap, const QwtScaleMap& yMap,
        const QRectF& canvasRect, int from, int to ) const QWT_OVERRIDE;
 
    virtual QRectF boundingRect() const QWT_OVERRIDE;
 
    virtual QwtGraphic legendIcon(
        int index, const QSizeF& ) const QWT_OVERRIDE;
 
  protected:
    virtual QwtColumnRect columnRect( const QwtIntervalSample&,
        const QwtScaleMap&, const QwtScaleMap& ) const;
 
    virtual void drawColumn( QPainter*, const QwtColumnRect&,
        const QwtIntervalSample& ) const;
 
    void drawColumns( QPainter*,
        const QwtScaleMap& xMap, const QwtScaleMap& yMap,
        int from, int to ) const;
 
    void drawOutline( QPainter*,
        const QwtScaleMap& xMap, const QwtScaleMap& yMap,
        int from, int to ) const;
 
    void drawLines( QPainter*,
        const QwtScaleMap& xMap, const QwtScaleMap& yMap,
        int from, int to ) const;
 
  private:
    void init();
    void flushPolygon( QPainter*, double baseLine, QPolygonF& ) const;
 
    class PrivateData;
    PrivateData* m_data;
};
 
#endif