# qwt_plot_rasteritem.h

    00001 /* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
    00002  * Qwt Widget Library
    00003  * Copyright (C) 1997   Josef Wilgen
    00004  * Copyright (C) 2002   Uwe Rathmann
    00005  *
    00006  * This library is free software; you can redistribute it and/or
    00007  * modify it under the terms of the Qwt License, Version 1.0
    00008  *****************************************************************************/
    00009
    00010 #ifndef QWT_PLOT_RASTERITEM_H
    00011 #define QWT_PLOT_RASTERITEM_H
    00012
    00013 #include <qglobal.h>
    00014 #include <qstring.h>
    00015 #include <qimage.h>
    00016
    00017 #include "qwt_plot_item.h"
    00018
    00036 class QWT_EXPORT QwtPlotRasterItem: public QwtPlotItem
    00037 {
    00038 public:
    00056     enum CachePolicy
    00057     {
    00058         NoCache,
    00059         PaintCache,
    00060         ScreenCache
    00061     };
    00062
    00063     explicit QwtPlotRasterItem(const QString& title = QString::null);
    00064     explicit QwtPlotRasterItem(const QwtText& title);
    00065     virtual ~QwtPlotRasterItem();
    00066
    00067     void setAlpha(int alpha);
    00068     int alpha() const;
    00069
    00070     void setCachePolicy(CachePolicy);
    00071     CachePolicy cachePolicy() const;
    00072
    00073     void invalidateCache();
    00074
    00075     virtual void draw(QPainter *p,
    00076         const QwtScaleMap &xMap, const QwtScaleMap &yMap,
    00077         const QRect &rect) const;
    00078
    00079     virtual QSize rasterHint(const QwtDoubleRect &) const;
    00080
    00081 protected:
    00082
    00093     virtual QImage renderImage(const QwtScaleMap &xMap,
    00094         const QwtScaleMap &yMap, const QwtDoubleRect &area
    00095         ) const = 0;
    00096
    00097 private:
    00098     QwtPlotRasterItem( const QwtPlotRasterItem & );
    00099     QwtPlotRasterItem &operator=( const QwtPlotRasterItem & );
    00100
    00101     void init();
    00102
    00103     class PrivateData;
    00104     PrivateData *d_data;
    00105 };
    00106
    00107 #endif