qwt_abstract_scale_draw.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_ABSTRACT_SCALE_DRAW_H
#define QWT_ABSTRACT_SCALE_DRAW_H
 
#include "qwt_global.h"
#include "qwt_scale_div.h"
 
class QwtText;
class QPalette;
class QPainter;
class QFont;
class QwtTransform;
class QwtScaleMap;
 
class QWT_EXPORT QwtAbstractScaleDraw
{
public:
    enum ScaleComponent
    {
        Backbone = 0x01,
 
        Ticks = 0x02,
 
        Labels = 0x04
    };
 
    Q_DECLARE_FLAGS(ScaleComponents, ScaleComponent)
 
    QwtAbstractScaleDraw();
    virtual ~QwtAbstractScaleDraw();
 
    void setScaleDiv(const QwtScaleDiv&);
    const QwtScaleDiv& scaleDiv() const;
 
    void setTransformation(QwtTransform*);
    const QwtScaleMap& scaleMap() const;
    QwtScaleMap& scaleMap();
 
    void enableComponent(ScaleComponent, bool enable = true);
    bool hasComponent(ScaleComponent) const;
 
    void setTickLength(QwtScaleDiv::TickType, double length);
    double tickLength(QwtScaleDiv::TickType) const;
    double maxTickLength() const;
 
    void setSpacing(double);
    double spacing() const;
 
    void setPenWidthF(qreal width);
    qreal penWidthF() const;
 
    // Set whether the scale draw is selected
    void setSelected(bool on);
    // Check if the scale draw is selected
    bool isSelected() const;
 
    // Set the pen width adjustment after selection
    void setSelectedPenWidthOffset(qreal offset = 1);
    qreal selectedPenWidthOffset() const;
 
    virtual void draw(QPainter*, const QPalette&) const;
 
    virtual QwtText label(double) const;
 
    // Calculate the extent (distance from baseline to outermost pixel)
    virtual double extent(const QFont& font) const = 0;
 
    void setMinimumExtent(double);
    double minimumExtent() const;
 
    void invalidateCache();
 
protected:
    // Draw a tick
    virtual void drawTick(QPainter* painter, double value, double len) const = 0;
 
    // Draws the baseline of the scale
    virtual void drawBackbone(QPainter* painter) const = 0;
 
    // Draws the label for a major scale tick
    virtual void drawLabel(QPainter* painter, double value) const = 0;
 
    const QwtText& tickLabel(const QFont&, double value) const;
 
private:
    QwtAbstractScaleDraw(const QwtAbstractScaleDraw&)            = delete;
    QwtAbstractScaleDraw& operator=(const QwtAbstractScaleDraw&) = delete;
 
    QWT_DECLARE_PRIVATE(QwtAbstractScaleDraw)
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS(QwtAbstractScaleDraw::ScaleComponents)
 
#endif