qwt_plot_abstract_barchart.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_ABSTRACT_BAR_CHART_H
#define QWT_PLOT_ABSTRACT_BAR_CHART_H
 
#include "qwt_global.h"
#include "qwt_plot_seriesitem.h"
 
class QWT_EXPORT QwtPlotAbstractBarChart : public QwtPlotSeriesItem
{
  public:
    enum LayoutPolicy
    {
        AutoAdjustSamples,
 
        ScaleSamplesToAxes,
 
        ScaleSampleToCanvas,
 
        FixedSampleSize
    };
 
    // Constructor with title
    explicit QwtPlotAbstractBarChart( const QwtText& title );
    // Destructor
    virtual ~QwtPlotAbstractBarChart();
 
    // Set the layout policy for bar width calculation
    void setLayoutPolicy( LayoutPolicy );
    // Get the layout policy
    LayoutPolicy layoutPolicy() const;
 
    // Set the layout hint for bar width calculation
    void setLayoutHint( double );
    // Get the layout hint
    double layoutHint() const;
 
    // Set the spacing between bars
    void setSpacing( int );
    // Get the spacing between bars
    int spacing() const;
 
    // Set the margin around the bars
    void setMargin( int );
    // Get the margin around the bars
    int margin() const;
 
    // Set the baseline value for the bars
    void setBaseline( double );
    // Get the baseline value
    double baseline() const;
 
    // Calculate canvas margin hint for layout
    virtual void getCanvasMarginHint(
        const QwtScaleMap& xMap, const QwtScaleMap& yMap,
        const QRectF& canvasRect, double& left, double& top,
        double& right, double& bottom) const override;
 
 
  protected:
    double sampleWidth( const QwtScaleMap& map,
        double canvasSize, double boundingSize,
        double value ) const;
 
  private:
    class PrivateData;
    PrivateData* m_data;
};
 
#endif