qwt_color_map.h

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * 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
 *****************************************************************************/

#ifndef QWT_COLOR_MAP_H
#define QWT_COLOR_MAP_H

#include <qglobal.h>
#include <qcolor.h>
#if QT_VERSION < 0x040000
#include <qvaluevector.h>
#else
#include <qvector.h>
#endif
#include "qwt_array.h"
#include "qwt_double_interval.h"

#if defined(QWT_TEMPLATEDLL)
// MOC_SKIP_BEGIN
template class QWT_EXPORT QwtArray<double>;
// MOC_SKIP_END
#endif

class QWT_EXPORT QwtColorMap
{
public:
    enum Format
    {
        RGB,
        Indexed
    };

    QwtColorMap(Format = QwtColorMap::RGB );
    virtual ~QwtColorMap();

    inline Format format() const;

    virtual QwtColorMap *copy() const = 0;

    virtual QRgb rgb(
        const QwtDoubleInterval &interval, double value) const = 0;

    virtual unsigned char colorIndex(
        const QwtDoubleInterval &interval, double value) const = 0;

    QColor color(const QwtDoubleInterval &, double value) const;
#if QT_VERSION < 0x040000
    virtual QValueVector<QRgb> colorTable(const QwtDoubleInterval &) const;
#else
    virtual QVector<QRgb> colorTable(const QwtDoubleInterval &) const;
#endif

private:
    Format d_format;
};


class QWT_EXPORT QwtLinearColorMap: public QwtColorMap
{
public:
    enum Mode
    {
        FixedColors,
        ScaledColors
    };

    QwtLinearColorMap(QwtColorMap::Format = QwtColorMap::RGB);
    QwtLinearColorMap( const QColor &from, const QColor &to,
        QwtColorMap::Format = QwtColorMap::RGB);

    QwtLinearColorMap(const QwtLinearColorMap &);

    virtual ~QwtLinearColorMap();

    QwtLinearColorMap &operator=(const QwtLinearColorMap &);

    virtual QwtColorMap *copy() const;

    void setMode(Mode);
    Mode mode() const;

    void setColorInterval(const QColor &color1, const QColor &color2);
    void addColorStop(double value, const QColor&);
    QwtArray<double> colorStops() const;

    QColor color1() const;
    QColor color2() const;

    virtual QRgb rgb(const QwtDoubleInterval &, double value) const;
    virtual unsigned char colorIndex(
        const QwtDoubleInterval &, double value) const;

    class ColorStops;

private:
    class PrivateData;
    PrivateData *d_data;
};

class QWT_EXPORT QwtAlphaColorMap: public QwtColorMap
{
public:
    QwtAlphaColorMap(const QColor & = QColor(Qt::gray));
    QwtAlphaColorMap(const QwtAlphaColorMap &);

    virtual ~QwtAlphaColorMap();

    QwtAlphaColorMap &operator=(const QwtAlphaColorMap &);

    virtual QwtColorMap *copy() const;

    void setColor(const QColor &);
    QColor color() const;

    virtual QRgb rgb(const QwtDoubleInterval &, double value) const;

private:
    virtual unsigned char colorIndex(
        const QwtDoubleInterval &, double value) const;

    class PrivateData;
    PrivateData *d_data;
};


inline QColor QwtColorMap::color(
    const QwtDoubleInterval &interval, double value) const
{
    if ( d_format == RGB )
    {
        return QColor( rgb(interval, value) );
    }
    else
    {
        const unsigned int index = colorIndex(interval, value);
        return colorTable(interval)[index]; // slow
    }
}

inline QwtColorMap::Format QwtColorMap::format() const
{
    return d_format;
}

#endif

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