C++ QwtGraphic类代码示例

/*!
  Minimum size hint needed to display an entry

  \param data Attributes of the legend entry
  \return Minimum size
 */
QSize QwtPlotLegendItem::minimumSize( const QwtLegendData &data ) const
{
    QSize size( 2 * d_data->itemMargin, 2 * d_data->itemMargin );

    if ( !data.isValid() )
        return size;

    const QwtGraphic graphic = data.icon();
    const QwtText text = data.title();

    int w = 0;
    int h = 0;

    if ( !graphic.isNull() )
    {
        w = graphic.width();
        h = graphic.height();
    }

    if ( !text.isEmpty() )
    {
        const QSizeF sz = text.textSize( font() );

        w += qCeil( sz.width() );
        h = qMax( h, qCeil( sz.height() ) );
    }

    if ( graphic.width() > 0 && !text.isEmpty() )
        w += d_data->itemSpacing;

    size += QSize( w, h );
    return size;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void RimPlotCurve::updateUiIconFromPlotSymbol()
{
    if (m_pointSymbol() != RiuQwtSymbol::NoSymbol)
    {
        QColor curveColor(m_curveColor.value().rByte(), m_curveColor.value().gByte(), m_curveColor.value().bByte());

        QSizeF iconSize(24, 24);
        QwtGraphic graphic = m_qwtPlotCurve->legendIcon(0, iconSize);
        QPixmap pixmap = graphic.toPixmap();
        setUiIcon(QIcon(pixmap));
    }
}

static QwtGraphic qwtPathGraphic( const QPainterPath &path, 
    const QPen &pen, const QBrush& brush )
{
    QwtGraphic graphic;
    graphic.setRenderHint( QwtGraphic::RenderPensUnscaled );

    QPainter painter( &graphic );
    painter.setPen( pen );
    painter.setBrush( brush );
    painter.drawPath( path );
    painter.end();

    return graphic;
}

/*!
  \return Icon for the legend

  In case of Tube style() the icon is a plain rectangle filled with the brush().
  If a symbol is assigned it is scaled to size.

  \param index Index of the legend entry 
               ( ignored as there is only one )
  \param size Icon size
    
  \sa QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData()
*/
QwtGraphic QwtPlotIntervalCurve::legendIcon( 
    int index, const QSizeF &size ) const
{
    Q_UNUSED( index );

    if ( size.isEmpty() )
        return QwtGraphic();

    QwtGraphic icon;
    icon.setDefaultSize( size );
    icon.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &icon );
    painter.setRenderHint( QPainter::Antialiasing,
        testRenderHint( QwtPlotItem::RenderAntialiased ) );

    if ( d_data->style == Tube )
    {
        QRectF r( 0, 0, size.width(), size.height() );
        painter.fillRect( r, d_data->brush );
    }

    if ( d_data->symbol &&
        ( d_data->symbol->style() != QwtIntervalSymbol::NoSymbol ) )
    {
        QPen pen = d_data->symbol->pen();
        pen.setWidthF( pen.widthF() );
        pen.setCapStyle( Qt::FlatCap );

        painter.setPen( pen );
        painter.setBrush( d_data->symbol->brush() );

        if ( orientation() == Qt::Vertical )
        {
            const double x = 0.5 * size.width();

            d_data->symbol->draw( &painter, orientation(),
                QPointF( x, 0 ), QPointF( x, size.height() - 1.0 ) );
        }
        else
        {
            const double y = 0.5 * size.height();

            d_data->symbol->draw( &painter, orientation(),
                QPointF( 0.0, y ), QPointF( size.width() - 1.0, y ) );
        }
    }

    return icon;
}

/*!
   \return Icon representing the marker on the legend

   \param index Index of the legend entry 
                ( usually there is only one )
   \param size Icon size

   \sa setLegendIconSize(), legendData()
*/
QwtGraphic QwtPlotMarker::legendIcon( int index,
    const QSizeF &size ) const
{
    Q_UNUSED( index );

    if ( size.isEmpty() )
        return QwtGraphic();

    QwtGraphic icon;
    icon.setDefaultSize( size );
    icon.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &icon );
    painter.setRenderHint( QPainter::Antialiasing,
        testRenderHint( QwtPlotItem::RenderAntialiased ) );

    if ( d_data->style != QwtPlotMarker::NoLine )
    {
        painter.setPen( d_data->pen );

        if ( d_data->style == QwtPlotMarker::HLine ||
            d_data->style == QwtPlotMarker::Cross )
        {
            const double y = 0.5 * size.height();

            QwtPainter::drawLine( &painter, 
                0.0, y, size.width(), y );
        }

        if ( d_data->style == QwtPlotMarker::VLine ||
            d_data->style == QwtPlotMarker::Cross )
        {
            const double x = 0.5 * size.width();

            QwtPainter::drawLine( &painter, 
                x, 0.0, x, size.height() );
        }
    }

    if ( d_data->symbol )
    {
        const QRect r( 0.0, 0.0, size.width(), size.height() );
        d_data->symbol->drawSymbol( &painter, r );
    }

    return icon;
}

/*!
  \return Icon for representing a bar on the legend

  \param index Index of the bar
  \param size Icon size
  
  \return An icon showing a bar
  \sa drawBar(), legendData()
 */
QwtGraphic QwtPlotMultiBarChart::legendIcon( int index,
    const QSizeF &size ) const
{
    QwtColumnRect column;
    column.hInterval = QwtInterval( 0.0, size.width() - 1.0 );
    column.vInterval = QwtInterval( 0.0, size.height() - 1.0 );

    QwtGraphic icon;
    icon.setDefaultSize( size );
    icon.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &icon );
    painter.setRenderHint( QPainter::Antialiasing,
        testRenderHint( QwtPlotItem::RenderAntialiased ) );

    drawBar( &painter, -1, index, column );

    return icon;
}

static inline QRectF qwtScaledBoundingRect( 
    const QwtGraphic &graphic, const QSizeF size )
{
    QSizeF scaledSize = size;
    if ( scaledSize.isEmpty() )
        scaledSize = graphic.defaultSize();
        
    const QSizeF sz = graphic.controlPointRect().size();

    double sx = 1.0;
    if ( sz.width() > 0.0 )
        sx = scaledSize.width() / sz.width();
    
    double sy = 1.0;
    if ( sz.height() > 0.0 )
        sy = scaledSize.height() / sz.height();

    return graphic.scaledBoundingRect( sx, sy );
}

QwtGraphic Plot2DProfile::legendIcon( int /*index*/, const QSizeF& iconSize ) const {
    if ( iconSize.isEmpty() ){
        return QwtGraphic();
    }
    QwtGraphic icon;
    icon.setDefaultSize( iconSize );
    icon.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &icon );
    QPen pen( m_defaultColor );
    pen.setStyle( m_penStyle );
    pen.setWidth( 3 );
    const double y = 0.5 * iconSize.height();
    QPainterPath path;
    path.moveTo( 0.0, y );
    path.lineTo( iconSize.width(), y );
    painter.strokePath( path, pen );
    return icon;
}

/*!
  \return The preferred height, for a width.
  \param data Attributes of the legend entry
  \param width Width
*/
int QwtPlotLegendItem::heightForWidth( 
    const QwtLegendData &data, int width ) const
{
    width -= 2 * d_data->itemMargin;

    const QwtGraphic graphic = data.icon();
    const QwtText text = data.title();

    if ( text.isEmpty() )
        return graphic.height();

    if ( graphic.width() > 0 )
        width -= graphic.width() + d_data->itemSpacing;

    int h = text.heightForWidth( width, font() );
    h += 2 * d_data->itemMargin;

    return qMax( graphic.height(), h );
}

static inline void qwtDrawGraphicSymbols( QPainter *painter, 
    const QPointF *points, int numPoints, const QwtGraphic &graphic,
    const QwtSymbol &symbol )
{
    const QRectF pointRect = graphic.controlPointRect();
    if ( pointRect.isEmpty() )
        return;

    double sx = 1.0;
    double sy = 1.0;

    const QSize sz = symbol.size();
    if ( sz.isValid() )
    {
        sx = sz.width() / pointRect.width();
        sy = sz.height() / pointRect.height();
    }

    QPointF pinPoint = pointRect.center();
    if ( symbol.isPinPointEnabled() )
        pinPoint = symbol.pinPoint();

    const QTransform transform = painter->transform();

    for ( int i = 0; i < numPoints; i++ )
    {
        QTransform tr = transform;
        tr.translate( points[i].x(), points[i].y() );
        tr.scale( sx, sy );
        tr.translate( -pinPoint.x(), -pinPoint.y() );

        painter->setTransform( tr );

        graphic.render( painter );
    }

    painter->setTransform( transform );
}

/*!
  \return A rectangle filled with the color of the brush ( or the pen )

  \param index Index of the legend entry 
                ( usually there is only one )
  \param size Icon size

  \sa setLegendIconSize(), legendData()
*/
QwtGraphic QwtPlotShapeItem::legendIcon( int index,
    const QSizeF &size ) const
{
    Q_UNUSED( index );

    QwtGraphic icon;
    icon.setDefaultSize( size );

    if ( size.isEmpty() )
        return icon;

    if ( d_data->legendMode == QwtPlotShapeItem::LegendShape )
    {
        const QRectF &br = d_data->boundingRect;

        QPainter painter( &icon );
        painter.setRenderHint( QPainter::Antialiasing,
            testRenderHint( QwtPlotItem::RenderAntialiased ) );

        painter.translate( -br.topLeft() );

        painter.setPen( d_data->pen );
        painter.setBrush( d_data->brush );
        painter.drawPath( d_data->shape );
    }
    else
    {
        QColor iconColor;
        if ( d_data->brush.style() != Qt::NoBrush )
            iconColor = d_data->brush.color();
        else
            iconColor = d_data->pen.color();

        icon = defaultIcon( iconColor, size );
    }

    return icon;
}

/*!
   \return Icon representing a bar or the chart on the legend

   When the legendMode() is LegendBarTitles the icon shows
   the bar corresponding to index - otherwise the bar
   displays the default symbol.

   \param index Index of the legend entry 
   \param size Icon size

   \sa setLegendMode(), drawBar(), 
       QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData()
 */
QwtGraphic QwtPlotBarChart::legendIcon( 
    int index, const QSizeF &size ) const
{
    QwtColumnRect column;
    column.hInterval = QwtInterval( 0.0, size.width() - 1.0 );
    column.vInterval = QwtInterval( 0.0, size.height() - 1.0 );

    QwtGraphic icon;
    icon.setDefaultSize( size );
    icon.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &icon );
    painter.setRenderHint( QPainter::Antialiasing,
        testRenderHint( QwtPlotItem::RenderAntialiased ) );

    int barIndex = -1;
    if ( d_data->legendMode == QwtPlotBarChart::LegendBarTitles )
        barIndex = index;
        
    drawBar( &painter, barIndex, QPointF(), column );

    return icon;
}

/*!
  Draw an entry on the legend

  \param painter Qt Painter
  \param plotItem Plot item, represented by the entry
  \param data Attributes of the legend entry
  \param rect Bounding rectangle for the entry
 */
void QwtPlotLegendItem::drawLegendData( QPainter *painter,
    const QwtPlotItem *plotItem, const QwtLegendData &data, 
    const QRectF &rect ) const
{
    Q_UNUSED( plotItem );

    const int m = d_data->itemMargin;
    const QRectF r = rect.toRect().adjusted( m, m, -m, -m );

    painter->setClipRect( r, Qt::IntersectClip );

    int titleOff = 0;

    const QwtGraphic graphic = data.icon();
    if ( !graphic.isEmpty() )
    {
        QRectF iconRect( r.topLeft(), graphic.defaultSize() );

        iconRect.moveCenter( 
            QPoint( iconRect.center().x(), rect.center().y() ) );

        graphic.render( painter, iconRect, Qt::KeepAspectRatio );

        titleOff += iconRect.width() + d_data->itemSpacing;
    }

    const QwtText text = data.title();
    if ( !text.isEmpty() )
    {
        painter->setPen( textPen() );
        painter->setFont( font() );

        const QRectF textRect = r.adjusted( titleOff, 0, 0, 0 );
        text.draw( painter, textRect );
    }
}

/*!
   \brief Return all information, that is needed to represent
          the item on the legend

   Most items are represented by one entry on the legend
   showing an icon and a text.

   QwtLegendData is basically a list of QVariants that makes it
   possible to overload and reimplement legendData() to 
   return almost any type of information, that is understood
   by the receiver that acts as the legend.

   The default implementation returns one entry with 
   the title() of the item and the legendIcon().

   \sa title(), legendIcon(), QwtLegend
 */
QList<QwtLegendData> QwtPolarItem::legendData() const
{
    QwtLegendData data;

    QwtText label = title();
    label.setRenderFlags( label.renderFlags() & Qt::AlignLeft );

    QVariant titleValue;
    qVariantSetValue( titleValue, label );
    data.setValue( QwtLegendData::TitleRole, titleValue );

    const QwtGraphic graphic = legendIcon( 0, legendIconSize() );
    if ( !graphic.isNull() )
    {
        QVariant iconValue;
        qVariantSetValue( iconValue, graphic );
        data.setValue( QwtLegendData::IconRole, iconValue );
    }

    QList<QwtLegendData> list;
    list += data;

    return list;
}

/*!
   \return Icon representing the curve on the legend

   \param index Index of the legend entry 
                ( ignored as there is only one )
   \param size Icon size

   \sa QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData()
 */
QwtGraphic QwtPlotCurve::legendIcon( int index, 
    const QSizeF &size ) const
{
    Q_UNUSED( index );

    if ( size.isEmpty() )
        return QwtGraphic();

    QwtGraphic graphic;
    graphic.setDefaultSize( size );
    graphic.setRenderHint( QwtGraphic::RenderPensUnscaled, true );

    QPainter painter( &graphic );
    painter.setRenderHint( QPainter::Antialiasing,
        testRenderHint( QwtPlotItem::RenderAntialiased ) );

    if ( d_data->legendAttributes == 0 ||
        d_data->legendAttributes & QwtPlotCurve::LegendShowBrush )
    {
        QBrush brush = d_data->brush;

        if ( brush.style() == Qt::NoBrush &&
            d_data->legendAttributes == 0 )
        {
            if ( style() != QwtPlotCurve::NoCurve )
            {
                brush = QBrush( pen().color() );
            }
            else if ( d_data->symbol &&
                ( d_data->symbol->style() != QwtSymbol::NoSymbol ) )
            {
                brush = QBrush( d_data->symbol->pen().color() );
            }
        }

        if ( brush.style() != Qt::NoBrush )
        {
            QRectF r( 0, 0, size.width(), size.height() );
            painter.fillRect( r, brush );
        }
    }

    if ( d_data->legendAttributes & QwtPlotCurve::LegendShowLine )
    {
        if ( pen() != Qt::NoPen )
        {
            QPen pn = pen();
            pn.setCapStyle( Qt::FlatCap );

            painter.setPen( pn );

            const double y = 0.5 * size.height();
            QwtPainter::drawLine( &painter, 0.0, y, size.width(), y );
        }
    }

    if ( d_data->legendAttributes & QwtPlotCurve::LegendShowSymbol )
    {
        if ( d_data->symbol )
        {
            QRectF r( 0, 0, size.width(), size.height() );
            d_data->symbol->drawSymbol( &painter, r );
        }
    }

    return graphic;
}