qwt_plot_axis_zoomer.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_AXIS_ZOOMER_H
#define QWT_PLOT_AXIS_ZOOMER_H
 
#include "qwt_global.h"
#include "qwt_plot_picker.h"
 
class QSizeF;
template< typename T >
class QStack;
 
class QWT_EXPORT QwtPlotAxisZoomer : public QwtPlotPicker
{
    Q_OBJECT
public:
    // Constructor
    explicit QwtPlotAxisZoomer(QWidget*, bool doReplot = true);
    // Constructor with specified axes
    explicit QwtPlotAxisZoomer(QwtAxisId xAxis, QwtAxisId yAxis, QWidget*, bool doReplot = true);
 
    // Destructor
    ~QwtPlotAxisZoomer() override;
 
    // Set zoom base from current scales
    virtual void setZoomBase(bool doReplot = true);
    // Set zoom base from a rectangle
    virtual void setZoomBase(const QRectF&);
 
    // Get zoom base rectangle
    QRectF zoomBase() const;
    // Get current zoom rectangle
    QRectF zoomRect() const;
 
    // Set the axes for the zoomer
    virtual void setAxes(QwtAxisId xAxis, QwtAxisId yAxis) override;
 
    // Set maximum zoom stack depth
    void setMaxStackDepth(int);
    // Get maximum zoom stack depth
    int maxStackDepth() const;
 
    // Get the zoom stack
    const QStack< QRectF >& zoomStack() const;
    // Set the zoom stack
    void setZoomStack(const QStack< QRectF >&, int zoomRectIndex = -1);
 
    // Get current zoom rectangle index in stack
    uint zoomRectIndex() const;
 
public Q_SLOTS:
    // Move zoom rectangle by offset
    void moveBy(double dx, double dy);
    // Move zoom rectangle to position
    virtual void moveTo(const QPointF&);
 
    // Zoom to a rectangle
    virtual void zoom(const QRectF&);
    // Zoom by offset in stack
    virtual void zoom(int offset);
 
Q_SIGNALS:
    void zoomed(const QRectF& rect);
 
protected:
    virtual void rescale();
 
    virtual QSizeF minZoomSize() const;
 
    virtual void widgetMouseReleaseEvent(QMouseEvent*) override;
    virtual void widgetKeyPressEvent(QKeyEvent*) override;
 
    virtual void begin() override;
    virtual bool end(bool ok = true) override;
    virtual bool accept(QPolygon&) const override;
 
private:
    void init(bool doReplot);
 
    QWT_DECLARE_PRIVATE(QwtPlotAxisZoomer)
};
 
#endif