qwt_painter_command.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_PAINTER_COMMAND_H
#define QWT_PAINTER_COMMAND_H

#include "qwt_global.h"
#include <qpaintengine.h>
#include <qpixmap.h>
#include <qimage.h>
#include <qpolygon.h>

class QPainterPath;

/*!
  QwtPainterCommand represents the attributes of a paint operation
  how it is used between QPainter and QPaintDevice

  It is used by QwtGraphic to record and replay paint operations

  \sa QwtGraphic::commands()
 */
  
class QWT_EXPORT QwtPainterCommand
{
public:
    //! Type of the paint command
    enum Type
    {
        //! Invalid command
        Invalid = -1,

        //! Draw a QPainterPath
        Path,

        //! Draw a QPixmap
        Pixmap,

        //! Draw a QImage
        Image,

        //! QPainter state change
        State
    };

    //! Attributes how to paint a QPixmap 
    struct PixmapData
    {
        QRectF rect;
        QPixmap pixmap;
        QRectF subRect;
    };

    //! Attributes how to paint a QImage 
    struct ImageData
    {
        QRectF rect;
        QImage image;
        QRectF subRect;
        Qt::ImageConversionFlags flags;
    };

    //! Attributes of a state change
    struct StateData
    {
        QPaintEngine::DirtyFlags flags;

        QPen pen;
        QBrush brush;
        QPointF brushOrigin;
        QBrush backgroundBrush;
        Qt::BGMode backgroundMode;
        QFont font;
        QMatrix matrix;
        QTransform transform;

        Qt::ClipOperation clipOperation;
        QRegion clipRegion;
        QPainterPath clipPath;
        bool isClipEnabled;

        QPainter::RenderHints renderHints;
        QPainter::CompositionMode compositionMode;
        qreal opacity;
    };

    QwtPainterCommand();
    QwtPainterCommand(const QwtPainterCommand &);

    QwtPainterCommand( const QPainterPath & );

    QwtPainterCommand( const QRectF &rect,
            const QPixmap &, const QRectF& subRect );

    QwtPainterCommand( const QRectF &rect,
            const QImage &, const QRectF& subRect,
            Qt::ImageConversionFlags );

    QwtPainterCommand( const QPaintEngineState & );

    ~QwtPainterCommand();

    QwtPainterCommand &operator=(const QwtPainterCommand & );

    Type type() const;

    QPainterPath *path();
    const QPainterPath *path() const;

    PixmapData* pixmapData();
    const PixmapData* pixmapData() const;

    ImageData* imageData();
    const ImageData* imageData() const;

    StateData* stateData();
    const StateData* stateData() const;

private:
    void copy( const QwtPainterCommand & );
    void reset();

    Type d_type;

    union
    {
        QPainterPath *d_path;
        PixmapData *d_pixmapData;
        ImageData *d_imageData;
        StateData *d_stateData;
    };
};

//! \return Type of the command
inline QwtPainterCommand::Type QwtPainterCommand::type() const
{
    return d_type;
}

//! \return Painter path to be painted
inline const QPainterPath *QwtPainterCommand::path() const
{
    return d_path;
}

//! \return Attributes how to paint a QPixmap
inline const QwtPainterCommand::PixmapData* 
QwtPainterCommand::pixmapData() const
{
    return d_pixmapData;
}

//! \return Attributes how to paint a QImage
inline const QwtPainterCommand::ImageData * 
QwtPainterCommand::imageData() const
{
    return d_imageData;
}

//! \return Attributes of a state change
inline const QwtPainterCommand::StateData * 
QwtPainterCommand::stateData() const
{
    return d_stateData;
}

#endif