void QgsVectorLayerEditBuffer::updateChangedAttributes( QgsFeature &f )
{
QgsAttributes attrs = f.attributes();
// remove all attributes that will disappear - from higher indices to lower
for ( int idx = mDeletedAttributeIds.count() - 1; idx >= 0; --idx )
{
attrs.remove( mDeletedAttributeIds[idx] );
}
// adjust size to accommodate added attributes
attrs.resize( attrs.count() + mAddedAttributes.count() );
// update changed attributes
if ( mChangedAttributeValues.contains( f.id() ) )
{
const QgsAttributeMap &map = mChangedAttributeValues[f.id()];
for ( QgsAttributeMap::const_iterator it = map.begin(); it != map.end(); ++it )
attrs[it.key()] = it.value();
}
f.setAttributes( attrs );
}
void QgsOverlayUtils::difference( const QgsFeatureSource &sourceA, const QgsFeatureSource &sourceB, QgsFeatureSink &sink, QgsProcessingContext &context, QgsProcessingFeedback *feedback, int &count, int totalCount, QgsOverlayUtils::DifferenceOutput outputAttrs )
{
QgsFeatureRequest requestB;
requestB.setSubsetOfAttributes( QgsAttributeList() );
if ( outputAttrs != OutputBA )
requestB.setDestinationCrs( sourceA.sourceCrs(), context.transformContext() );
QgsSpatialIndex indexB( sourceB.getFeatures( requestB ), feedback );
int fieldsCountA = sourceA.fields().count();
int fieldsCountB = sourceB.fields().count();
QgsAttributes attrs;
attrs.resize( outputAttrs == OutputA ? fieldsCountA : ( fieldsCountA + fieldsCountB ) );
if ( totalCount == 0 )
totalCount = 1; // avoid division by zero
QgsFeature featA;
QgsFeatureRequest requestA;
if ( outputAttrs == OutputBA )
requestA.setDestinationCrs( sourceB.sourceCrs(), context.transformContext() );
QgsFeatureIterator fitA = sourceA.getFeatures( requestA );
while ( fitA.nextFeature( featA ) )
{
if ( feedback->isCanceled() )
break;
if ( featA.hasGeometry() )
{
QgsGeometry geom( featA.geometry() );
QgsFeatureIds intersects = indexB.intersects( geom.boundingBox() ).toSet();
QgsFeatureRequest request;
request.setFilterFids( intersects );
request.setSubsetOfAttributes( QgsAttributeList() );
if ( outputAttrs != OutputBA )
request.setDestinationCrs( sourceA.sourceCrs(), context.transformContext() );
std::unique_ptr< QgsGeometryEngine > engine;
if ( !intersects.isEmpty() )
{
// use prepared geometries for faster intersection tests
engine.reset( QgsGeometry::createGeometryEngine( geom.constGet() ) );
engine->prepareGeometry();
}
QVector<QgsGeometry> geometriesB;
QgsFeature featB;
QgsFeatureIterator fitB = sourceB.getFeatures( request );
while ( fitB.nextFeature( featB ) )
{
if ( feedback->isCanceled() )
break;
if ( engine->intersects( featB.geometry().constGet() ) )
geometriesB << featB.geometry();
}
if ( !geometriesB.isEmpty() )
{
QgsGeometry geomB = QgsGeometry::unaryUnion( geometriesB );
geom = geom.difference( geomB );
}
if ( !sanitizeDifferenceResult( geom ) )
continue;
const QgsAttributes attrsA( featA.attributes() );
switch ( outputAttrs )
{
case OutputA:
attrs = attrsA;
break;
case OutputAB:
for ( int i = 0; i < fieldsCountA; ++i )
attrs[i] = attrsA[i];
break;
case OutputBA:
for ( int i = 0; i < fieldsCountA; ++i )
attrs[i + fieldsCountB] = attrsA[i];
break;
}
QgsFeature outFeat;
outFeat.setGeometry( geom );
outFeat.setAttributes( attrs );
sink.addFeature( outFeat, QgsFeatureSink::FastInsert );
}
else
{
// TODO: should we write out features that do not have geometry?
sink.addFeature( featA, QgsFeatureSink::FastInsert );
}
++count;
feedback->setProgress( count / ( double ) totalCount * 100. );
}
}