void QgsMeshVectorRenderer::drawVectorArrow( const QgsPointXY &lineStart, double xVal, double yVal, double magnitude )
{
QgsPointXY lineEnd;
double vectorLength;
double cosAlpha, sinAlpha;
if ( calcVectorLineEnd( lineEnd, vectorLength, cosAlpha, sinAlpha,
lineStart, xVal, yVal, magnitude ) )
return;
// Make a set of vector head coordinates that we will place at the end of each vector,
// scale, translate and rotate.
QgsPointXY vectorHeadPoints[3];
QVector<QPointF> finalVectorHeadPoints( 3 );
double vectorHeadWidthRatio = mCfg.arrowHeadWidthRatio();
double vectorHeadLengthRatio = mCfg.arrowHeadLengthRatio();
// First head point: top of ->
vectorHeadPoints[0].setX( -1.0 * vectorHeadLengthRatio );
vectorHeadPoints[0].setY( vectorHeadWidthRatio * 0.5 );
// Second head point: right of ->
vectorHeadPoints[1].setX( 0.0 );
vectorHeadPoints[1].setY( 0.0 );
// Third head point: bottom of ->
vectorHeadPoints[2].setX( -1.0 * vectorHeadLengthRatio );
vectorHeadPoints[2].setY( -1.0 * vectorHeadWidthRatio * 0.5 );
// Determine the arrow head coords
for ( int j = 0; j < 3; j++ )
{
finalVectorHeadPoints[j].setX( lineEnd.x()
+ ( vectorHeadPoints[j].x() * cosAlpha * vectorLength )
- ( vectorHeadPoints[j].y() * sinAlpha * vectorLength )
);
finalVectorHeadPoints[j].setY( lineEnd.y()
- ( vectorHeadPoints[j].x() * sinAlpha * vectorLength )
- ( vectorHeadPoints[j].y() * cosAlpha * vectorLength )
);
}
// Now actually draw the vector
mContext.painter()->drawLine( lineStart.toQPointF(), lineEnd.toQPointF() );
mContext.painter()->drawPolygon( finalVectorHeadPoints );
}
void QgsVectorLayerDiagramProvider::drawLabel( QgsRenderContext &context, pal::LabelPosition *label ) const
{
#if 1 // XXX strk
// features are pre-rotated but not scaled/translated,
// so we only disable rotation here. Ideally, they'd be
// also pre-scaled/translated, as suggested here:
// https://issues.qgis.org/issues/11856
QgsMapToPixel xform = context.mapToPixel();
xform.setMapRotation( 0, 0, 0 );
#else
const QgsMapToPixel &xform = context.mapToPixel();
#endif
QgsDiagramLabelFeature *dlf = dynamic_cast<QgsDiagramLabelFeature *>( label->getFeaturePart()->feature() );
QgsFeature feature;
feature.setFields( mFields );
feature.setValid( true );
feature.setId( label->getFeaturePart()->featureId() );
feature.setAttributes( dlf->attributes() );
context.expressionContext().setFeature( feature );
//calculate top-left point for diagram
//first, calculate the centroid of the label (accounts for PAL creating
//rotated labels when we do not want to draw the diagrams rotated)
double centerX = 0;
double centerY = 0;
for ( int i = 0; i < 4; ++i )
{
centerX += label->getX( i );
centerY += label->getY( i );
}
QgsPointXY outPt( centerX / 4.0, centerY / 4.0 );
//then, calculate the top left point for the diagram with this center position
QgsPointXY centerPt = xform.transform( outPt.x() - label->getWidth() / 2,
outPt.y() - label->getHeight() / 2 );
mSettings.renderer()->renderDiagram( feature, context, centerPt.toQPointF(), mSettings.dataDefinedProperties() );
//insert into label search tree to manipulate position interactively
mEngine->results()->mLabelSearchTree->insertLabel( label, label->getFeaturePart()->featureId(), mLayerId, QString(), QFont(), true, false );
}
