A plot item, which displays data in Scalable Vector Graphics (SVG) format. More...

#include <qwt_plot_svgitem.h>

Inheritance diagram for QwtPlotSvgItem:

Collaboration diagram for QwtPlotSvgItem:

Classes
class	PrivateData
Public Member Functions
	QwtPlotSvgItem (const QString &title=QString::null)
	Constructor.
	QwtPlotSvgItem (const QwtText &title)
	Constructor.
virtual	~QwtPlotSvgItem ()
	Destructor.
bool	loadFile (const QwtDoubleRect &, const QString &fileName)
bool	loadData (const QwtDoubleRect &, const QByteArray &)
virtual QwtDoubleRect	boundingRect () const
	Bounding rect of the item.
virtual void	draw (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &rect) const
virtual int	rtti () const
Protected Member Functions
void	render (QPainter *painter, const QwtDoubleRect &viewBox, const QRect &rect) const
QwtDoubleRect	viewBox (const QwtDoubleRect &area) const

Detailed Description

A plot item, which displays data in Scalable Vector Graphics (SVG) format.

SVG images are often used to display maps

Definition at line 31 of file qwt_plot_svgitem.h.

Constructor & Destructor Documentation

QwtPlotSvgItem::QwtPlotSvgItem ( const QString & title = QString::null ) [explicit]

Constructor.

Sets the following item attributes:

QwtPlotItem::AutoScale: true
QwtPlotItem::Legend: false

Parameters:

title Title

Definition at line 51 of file qwt_plot_svgitem.cpp.

                                                  :
    QwtPlotItem(QwtText(title))
{
    init();
}

QwtPlotSvgItem::QwtPlotSvgItem ( const QwtText & title ) [explicit]

Constructor.

Sets the following item attributes:

QwtPlotItem::AutoScale: true
QwtPlotItem::Legend: false

Parameters:

title Title

Definition at line 66 of file qwt_plot_svgitem.cpp.

                                                  :
    QwtPlotItem(title)
{
    init();
}

QwtPlotSvgItem::~QwtPlotSvgItem ( ) [virtual]

Destructor.

Definition at line 73 of file qwt_plot_svgitem.cpp.

{
    delete d_data;
}

Member Function Documentation

QwtDoubleRect QwtPlotSvgItem::boundingRect ( ) const [virtual]

Bounding rect of the item.

Reimplemented from QwtPlotItem.

Definition at line 142 of file qwt_plot_svgitem.cpp.

References QwtPlotSvgItem::PrivateData::boundingRect.

Referenced by draw(), and viewBox().

{
    return d_data->boundingRect;
}

void QwtPlotSvgItem::draw	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRect &	canvasRect
	)		const `[virtual]`

Draw the SVG item

Parameters:

painter	Painter
xMap	X-Scale Map
yMap	Y-Scale Map
canvasRect	Contents rect of the plot canvas

Implements QwtPlotItem.

Definition at line 170 of file qwt_plot_svgitem.cpp.

References boundingRect(), QwtDoubleRect::contains(), QwtPlotItem::invTransform(), QwtDoubleRect::isValid(), render(), QwtPlotItem::transform(), and viewBox().

{
    const QwtDoubleRect cRect = invTransform(xMap, yMap, canvasRect);
    const QwtDoubleRect bRect = boundingRect();
    if ( bRect.isValid() && cRect.isValid() )
    {
        QwtDoubleRect rect = bRect;
        if ( bRect.contains(cRect) )
            rect = cRect;

        const QRect r = transform(xMap, yMap, rect);
        render(painter, viewBox(rect), r);
    }
}

bool QwtPlotSvgItem::loadData	(	const QwtDoubleRect &	rect,
		const QByteArray &	data
	)

Load SVG data

Parameters:

rect	Bounding rectangle
data	in SVG format

Returns:: true, if the SVG data could be loaded

Definition at line 123 of file qwt_plot_svgitem.cpp.

References QwtPlotSvgItem::PrivateData::boundingRect, QwtPlotItem::itemChanged(), and QwtPlotSvgItem::PrivateData::picture.

{
    d_data->boundingRect = rect;
#if QT_VERSION >= 0x040100
    const bool ok = d_data->renderer.load(data);
#else
#if QT_VERSION >= 0x040000
    QBuffer buffer(&(QByteArray&)data);
#else
    QBuffer buffer(data);
#endif
    const bool ok = d_data->picture.load(&buffer, "svg");
#endif
    itemChanged();
    return ok;
}

bool QwtPlotSvgItem::loadFile	(	const QwtDoubleRect &	rect,
		const QString &	fileName
	)

Load a SVG file

Parameters:

rect	Bounding rectangle
fileName	SVG file name

Returns:: true, if the SVG file could be loaded

Definition at line 102 of file qwt_plot_svgitem.cpp.

References QwtPlotSvgItem::PrivateData::boundingRect, QwtPlotItem::itemChanged(), and QwtPlotSvgItem::PrivateData::picture.

{
    d_data->boundingRect = rect;
#if QT_VERSION >= 0x040100
    const bool ok = d_data->renderer.load(fileName);
#else
    const bool ok = d_data->picture.load(fileName, "svg");
#endif
    itemChanged();
    return ok;
}

void QwtPlotSvgItem::render	(	QPainter *	painter,
		const QwtDoubleRect &	viewBox,
		const QRect &	rect
	)		const `[protected]`

Render the SVG data

Parameters:

painter	Painter
viewBox	View Box, see QSvgRenderer::viewBox
rect	Traget rectangle on the paint device

Definition at line 194 of file qwt_plot_svgitem.cpp.

References QwtDoubleRect::height(), QwtDoubleRect::isValid(), QwtPlotSvgItem::PrivateData::picture, QwtDoubleRect::toRect(), QwtDoubleRect::width(), QwtDoubleRect::x(), and QwtDoubleRect::y().

Referenced by draw().

{
    if ( !viewBox.isValid() )
        return;

#if QT_VERSION >= 0x040200
    d_data->renderer.setViewBox(viewBox);
    d_data->renderer.render(painter, rect);
    return;
#else

#if QT_VERSION >= 0x040100
    const QSize paintSize(painter->window().width(),
        painter->window().height());
    if ( !paintSize.isValid() )
        return;

    const double xRatio = paintSize.width() / viewBox.width();
    const double yRatio = paintSize.height() / viewBox.height();

    const double dx = rect.left() / xRatio + 1.0;
    const double dy = rect.top() / yRatio + 1.0;

    const double mx = double(rect.width()) / paintSize.width();
    const double my = double(rect.height()) / paintSize.height();

    painter->save();

    painter->translate(dx, dy);
    painter->scale(mx, my);

    d_data->renderer.setViewBox(viewBox.toRect());
    d_data->renderer.render(painter);

    painter->restore();
#else
    const double mx = rect.width() / viewBox.width();
    const double my = rect.height() / viewBox.height();
    const double dx = rect.x() - mx * viewBox.x();
    const double dy = rect.y() - my * viewBox.y();

    painter->save();

    painter->translate(dx, dy);
    painter->scale(mx, my);
    
    d_data->picture.play(painter);

    painter->restore();
#endif // < 0x040100
#endif // < 0x040200
}

int QwtPlotSvgItem::rtti ( ) const [virtual]

Returns:: QwtPlotItem::Rtti_PlotSVG

Reimplemented from QwtPlotItem.

Definition at line 89 of file qwt_plot_svgitem.cpp.

References QwtPlotItem::Rtti_PlotSVG.

{
    return QwtPlotItem::Rtti_PlotSVG;
}

QwtDoubleRect QwtPlotSvgItem::viewBox ( const QwtDoubleRect & rect ) const [protected]

Calculate the viewBox from an rect and boundingRect().

Parameters:

rect	Rectangle in scale coordinates

Returns:: viewBox View Box, see QSvgRenderer::viewBox

Definition at line 254 of file qwt_plot_svgitem.cpp.

References QwtDoubleRect::bottom(), boundingRect(), QwtDoubleRect::isValid(), QwtDoubleRect::left(), QwtPlotSvgItem::PrivateData::picture, QwtDoubleRect::right(), QwtScaleMap::setPaintInterval(), QwtScaleMap::setScaleInterval(), QwtDoubleRect::top(), and QwtScaleMap::xTransform().

Referenced by draw().

{
#if QT_VERSION >= 0x040100
    const QSize sz = d_data->renderer.defaultSize();
#else
#if QT_VERSION > 0x040000
    const QSize sz(d_data->picture.width(), 
        d_data->picture.height());
#else
    QPaintDeviceMetrics metrics(&d_data->picture);
    const QSize sz(metrics.width(), metrics.height());
#endif
#endif
    const QwtDoubleRect br = boundingRect();

    if ( !rect.isValid() || !br.isValid() || sz.isNull() )
        return QwtDoubleRect();

    QwtScaleMap xMap;
    xMap.setScaleInterval(br.left(), br.right());
    xMap.setPaintInterval(0, sz.width());

    QwtScaleMap yMap;
    yMap.setScaleInterval(br.top(), br.bottom());
    yMap.setPaintInterval(sz.height(), 0);

    const double x1 = xMap.xTransform(rect.left());
    const double x2 = xMap.xTransform(rect.right());
    const double y1 = yMap.xTransform(rect.bottom());
    const double y2 = yMap.xTransform(rect.top());

    return QwtDoubleRect(x1, y1, x2 - x1, y2 - y1);
}

The documentation for this class was generated from the following files:

QwtPlotSvgItem Class Reference

Classes

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation