160 QPainter *p =
c.painter();
166 QList< QPair<double, QColor> > values;
167 QList< QPair<double, QColor> > negativeValues;
176 double negativeTotal = 0;
178 QList< QColor >::const_iterator colIt = s.
categoryColors.constBegin();
182 double currentVal = expression->
evaluate( &expressionContext ).toDouble();
183 total += fabs( currentVal );
184 if ( currentVal >= 0 )
186 values.push_back( qMakePair( currentVal, *colIt ) );
190 negativeTotal += currentVal;
191 negativeValues.push_back( qMakePair( -currentVal, *colIt ) );
198 const double totalSpacing = std::max( 0,
static_cast<int>( s.
categoryAttributes.size() ) - 1 ) * spacing;
200 double scaledMaxVal = 0;
213 if ( mApplySpacingAdjust )
214 scaledMaxVal -= totalSpacing;
216 double axisOffset = 0;
217 if ( !negativeValues.isEmpty() )
219 axisOffset = -negativeTotal / total * scaledMaxVal + ( negativeValues.size() - 1 ) * spacing;
223 double baseX = position.x();
224 double baseY = position.y();
239 while ( !negativeValues.isEmpty() )
241 values.push_front( negativeValues.takeLast() );
244 double currentOffset = 0;
245 QList< QPair<double, QColor> >::const_iterator valIt = values.constBegin();
246 for ( ; valIt != values.constEnd(); ++valIt )
248 double length = valIt->first / total * scaledMaxVal;
250 QColor brushColor( valIt->second );
251 brushColor.setAlphaF( brushColor.alphaF() * s.
opacity );
252 mCategoryBrush.setColor( brushColor );
253 p->setBrush( mCategoryBrush );
258 p->drawRect( QRectF( baseX, baseY - currentOffset, scaledWidth, length * -1 ) );
262 p->drawRect( QRectF( baseX, baseY + currentOffset - scaledMaxVal - spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ), scaledWidth, length ) );
266 p->drawRect( QRectF( baseX + currentOffset, baseY - scaledWidth, length, scaledWidth ) );
270 p->drawRect( QRectF( baseX + scaledMaxVal - currentOffset + spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ), baseY - scaledWidth, 0 - length, scaledWidth ) );
274 currentOffset += length + spacing;
280 QPolygonF axisPoints;
284 axisPoints << QPointF( baseX, baseY - scaledMaxVal - spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ) )
285 << QPointF( baseX, baseY - axisOffset )
286 << QPointF( baseX + scaledWidth, baseY - axisOffset );
290 axisPoints << QPointF( baseX, baseY )
291 << QPointF( baseX, baseY - scaledMaxVal - spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ) + axisOffset )
292 << QPointF( baseX + scaledWidth, baseY - scaledMaxVal - spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ) + axisOffset );
296 axisPoints << QPointF( baseX + scaledMaxVal + spacing * std::max( 0, static_cast<int>( values.size() ) - 1 ), baseY - scaledWidth )
297 << QPointF( baseX + axisOffset, baseY - scaledWidth )
298 << QPointF( baseX + axisOffset, baseY );
302 axisPoints << QPointF( baseX, baseY - scaledWidth )
303 << QPointF( baseX + scaledMaxVal + spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ) - axisOffset, baseY - scaledWidth )
304 << QPointF( baseX + scaledMaxVal + spacing * std::max( 0,
static_cast<int>( values.size() ) - 1 ) - axisOffset, baseY );
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
void setFeature(const QgsFeature &feature)
Convenience function for setting a feature for the context.
void setFields(const QgsFields &fields)
Convenience function for setting a fields for the context.
Contains information about the context of a rendering operation.