/*!
Redraw the canvas.
\param painter Painter used for drawing
\param canvasRect Contents rect of the canvas
*/
void QwtPolarPlot::drawCanvas( QPainter *painter,
const QRectF &canvasRect ) const
{
const QRectF cr = canvasRect;
const QRectF pr = plotRect( cr );
const double radius = pr.width() / 2.0;
if ( d_data->canvasBrush.style() != Qt::NoBrush )
{
painter->save();
painter->setPen( Qt::NoPen );
painter->setBrush( d_data->canvasBrush );
if ( qwtDistance( pr.center(), cr.topLeft() ) < radius &&
qwtDistance( pr.center(), cr.topRight() ) < radius &&
qwtDistance( pr.center(), cr.bottomRight() ) < radius &&
qwtDistance( pr.center(), cr.bottomLeft() ) < radius )
{
QwtPainter::drawRect( painter, cr );
}
else
{
painter->setRenderHint( QPainter::Antialiasing, true );
QwtPainter::drawEllipse( painter, pr );
}
painter->restore();
}
drawItems( painter,
scaleMap( QwtPolar::Azimuth, radius ),
scaleMap( QwtPolar::Radius, radius ),
pr.center(), radius, canvasRect );
}
/*!
Calculate the bounding interval of the radial scale that is
visible on the canvas.
*/
QwtDoubleInterval QwtPolarPlot::visibleInterval() const
{
const QwtScaleDiv *sd = scaleDiv( QwtPolar::Radius );
const QwtDoubleRect cRect = canvas()->contentsRect();
const QwtDoubleRect pRect = plotRect( cRect.toRect() );
if ( cRect.contains( pRect.toRect() ) || !cRect.intersects( pRect ) )
{
#if QWT_VERSION < 0x050200
return QwtDoubleInterval( sd->lBound(), sd->hBound() );
#else
return QwtDoubleInterval( sd->lowerBound(), sd->upperBound() );
#endif
}
const QwtDoublePoint pole = pRect.center();
const QwtDoubleRect scaleRect = pRect & cRect;
const QwtScaleMap map = scaleMap( QwtPolar::Radius );
double dmin = 0.0;
double dmax = 0.0;
if ( scaleRect.contains( pole ) )
{
dmin = 0.0;
QwtDoublePoint corners[4];
corners[0] = scaleRect.bottomRight();
corners[1] = scaleRect.topRight();
corners[2] = scaleRect.topLeft();
corners[3] = scaleRect.bottomLeft();
dmax = 0.0;
for ( int i = 0; i < 4; i++ )
{
const double dist = qwtDistance( pole, corners[i] );
if ( dist > dmax )
dmax = dist;
}
}
else
{
if ( pole.x() < scaleRect.left() )
{
if ( pole.y() < scaleRect.top() )
{
dmin = qwtDistance( pole, scaleRect.topLeft() );
dmax = qwtDistance( pole, scaleRect.bottomRight() );
}
else if ( pole.y() > scaleRect.bottom() )
{
dmin = qwtDistance( pole, scaleRect.bottomLeft() );
dmax = qwtDistance( pole, scaleRect.topRight() );
}
else
{
dmin = scaleRect.left() - pole.x();
dmax = qwtMax( qwtDistance( pole, scaleRect.bottomRight() ),
qwtDistance( pole, scaleRect.topRight() ) );
}
}
else if ( pole.x() > scaleRect.right() )
{
if ( pole.y() < scaleRect.top() )
{
dmin = qwtDistance( pole, scaleRect.topRight() );
dmax = qwtDistance( pole, scaleRect.bottomLeft() );
}
else if ( pole.y() > scaleRect.bottom() )
{
dmin = qwtDistance( pole, scaleRect.bottomRight() );
dmax = qwtDistance( pole, scaleRect.topLeft() );
}
else
{
dmin = pole.x() - scaleRect.right();
dmax = qwtMax( qwtDistance( pole, scaleRect.bottomLeft() ),
qwtDistance( pole, scaleRect.topLeft() ) );
}
}
else if ( pole.y() < scaleRect.top() )
{
dmin = scaleRect.top() - pole.y();
dmax = qwtMax( qwtDistance( pole, scaleRect.bottomLeft() ),
qwtDistance( pole, scaleRect.bottomRight() ) );
}
else if ( pole.y() > scaleRect.bottom() )
{
dmin = pole.y() - scaleRect.bottom();
dmax = qwtMax( qwtDistance( pole, scaleRect.topLeft() ),
qwtDistance( pole, scaleRect.topRight() ) );
}
}
const double radius = pRect.width() / 2.0;
if ( dmax > radius )
dmax = radius;
QwtDoubleInterval interval;
interval.setMinValue( map.invTransform( dmin ) );
interval.setMaxValue( map.invTransform( dmax ) );
return interval;
}
