qwt_plot_rasteritem.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_PLOT_RASTERITEM_H
#define QWT_PLOT_RASTERITEM_H

#include "qwt_global.h"
#include "qwt_plot_item.h"
#include "qwt_interval.h"
#include <qglobal.h>
#include <qstring.h>
#include <qimage.h>

class QWT_EXPORT QwtPlotRasterItem: public QwtPlotItem
{
public:
    enum CachePolicy
    {
        NoCache,
        PaintCache
    };

    enum PaintAttribute
    {
        PaintInDeviceResolution = 1
    };

    typedef QFlags<PaintAttribute> PaintAttributes;

    explicit QwtPlotRasterItem( const QString& title = QString::null );
    explicit QwtPlotRasterItem( const QwtText& title );
    virtual ~QwtPlotRasterItem();

    void setPaintAttribute( PaintAttribute, bool on = true );
    bool testPaintAttribute( PaintAttribute ) const;

    void setAlpha( int alpha );
    int alpha() const;

    void setCachePolicy( CachePolicy );
    CachePolicy cachePolicy() const;

    void invalidateCache();

    virtual void draw( QPainter *p,
        const QwtScaleMap &xMap, const QwtScaleMap &yMap,
        const QRectF &rect ) const;

    virtual QRectF pixelHint( const QRectF & ) const;

    virtual QwtInterval interval(Qt::Axis) const;
    virtual QRectF boundingRect() const;

protected:
    virtual QImage renderImage( const QwtScaleMap &xMap,
        const QwtScaleMap &yMap, const QRectF &area,
        const QSize &imageSize ) const = 0;

    virtual QwtScaleMap imageMap( Qt::Orientation,
        const QwtScaleMap &map, const QRectF &area,
        const QSize &imageSize, double pixelSize) const;

private:
    QwtPlotRasterItem( const QwtPlotRasterItem & );
    QwtPlotRasterItem &operator=( const QwtPlotRasterItem & );

    void init();

    QImage compose( const QwtScaleMap &, const QwtScaleMap &,
        const QRectF &imageArea, const QRectF &paintRect,
        const QSize &imageSize, bool doCache) const;


    class PrivateData;
    PrivateData *d_data;
};

Q_DECLARE_OPERATORS_FOR_FLAGS( QwtPlotRasterItem::PaintAttributes )

#endif