qwt_plot_canvas.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_CANVAS_H
#define QWT_PLOT_CANVAS_H
 
#include "qwt_global.h"
#include "qwt_plot_abstract_canvas.h"
 
#include <qframe.h>
#include <qpainterpath.h>
 
class QwtPlot;
class QPixmap;
class QPainterPath;
 
class QWT_EXPORT QwtPlotCanvas : public QFrame, public QwtPlotAbstractCanvas
{
    Q_OBJECT
 
    Q_PROPERTY(double borderRadius READ borderRadius WRITE setBorderRadius)
 
public:
    enum PaintAttribute
    {
        BackingStore = 1,
 
        Opaque = 2,
 
        HackStyledBackground = 4,
 
        ImmediatePaint = 8
    };
 
    Q_DECLARE_FLAGS(PaintAttributes, PaintAttribute)
 
    // Constructor
    explicit QwtPlotCanvas(QwtPlot* = nullptr);
    // Destructor
    ~QwtPlotCanvas() override;
 
    // Set paint attribute
    void setPaintAttribute(PaintAttribute, bool on = true);
    // Test paint attribute
    bool testPaintAttribute(PaintAttribute) const;
 
    // Get backing store
    const QPixmap* backingStore() const;
    // Invalidate backing store
    Q_INVOKABLE void invalidateBackingStore();
 
    // Handle events
    virtual bool event(QEvent*) override;
 
    // Get border path
    Q_INVOKABLE QPainterPath borderPath(const QRect&) const;
 
public Q_SLOTS:
    // Replot the canvas
    void replot();
 
protected:
    virtual void paintEvent(QPaintEvent*) override;
    virtual void resizeEvent(QResizeEvent*) override;
 
    virtual void drawBorder(QPainter*) override;
 
private:
    QWT_DECLARE_PRIVATE(QwtPlotCanvas)
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS(QwtPlotCanvas::PaintAttributes)
 
#endif