void QgsOverlayUtils::intersection( const QgsFeatureSource &sourceA, const QgsFeatureSource &sourceB, QgsFeatureSink &sink, QgsProcessingContext &context, QgsProcessingFeedback *feedback, int &count, int totalCount, const QList<int> &fieldIndicesA, const QList<int> &fieldIndicesB )
{
QgsWkbTypes::GeometryType geometryType = QgsWkbTypes::geometryType( QgsWkbTypes::multiType( sourceA.wkbType() ) );
int attrCount = fieldIndicesA.count() + fieldIndicesB.count();
QgsFeatureRequest request;
request.setSubsetOfAttributes( QgsAttributeList() );
request.setDestinationCrs( sourceA.sourceCrs(), context.transformContext() );
QgsFeature outFeat;
QgsSpatialIndex indexB( sourceB.getFeatures( request ), feedback );
if ( totalCount == 0 )
totalCount = 1; // avoid division by zero
QgsFeature featA;
QgsFeatureIterator fitA = sourceA.getFeatures( QgsFeatureRequest().setSubsetOfAttributes( fieldIndicesA ) );
while ( fitA.nextFeature( featA ) )
{
if ( feedback->isCanceled() )
break;
if ( !featA.hasGeometry() )
continue;
QgsGeometry geom( featA.geometry() );
QgsFeatureIds intersects = indexB.intersects( geom.boundingBox() ).toSet();
QgsFeatureRequest request;
request.setFilterFids( intersects );
request.setDestinationCrs( sourceA.sourceCrs(), context.transformContext() );
request.setSubsetOfAttributes( fieldIndicesB );
std::unique_ptr< QgsGeometryEngine > engine;
if ( !intersects.isEmpty() )
{
// use prepared geometries for faster intersection tests
engine.reset( QgsGeometry::createGeometryEngine( geom.constGet() ) );
engine->prepareGeometry();
}
QgsAttributes outAttributes( attrCount );
const QgsAttributes attrsA( featA.attributes() );
for ( int i = 0; i < fieldIndicesA.count(); ++i )
outAttributes[i] = attrsA[fieldIndicesA[i]];
QgsFeature featB;
QgsFeatureIterator fitB = sourceB.getFeatures( request );
while ( fitB.nextFeature( featB ) )
{
if ( feedback->isCanceled() )
break;
QgsGeometry tmpGeom( featB.geometry() );
if ( !engine->intersects( tmpGeom.constGet() ) )
continue;
QgsGeometry intGeom = geom.intersection( tmpGeom );
if ( !sanitizeIntersectionResult( intGeom, geometryType ) )
continue;
const QgsAttributes attrsB( featB.attributes() );
for ( int i = 0; i < fieldIndicesB.count(); ++i )
outAttributes[fieldIndicesA.count() + i] = attrsB[fieldIndicesB[i]];
outFeat.setGeometry( intGeom );
outFeat.setAttributes( outAttributes );
sink.addFeature( outFeat, QgsFeatureSink::FastInsert );
}
++count;
feedback->setProgress( count / ( double ) totalCount * 100. );
}
}
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. );
}
}
bool QgsProcessingAlgorithm::validateInputCrs( const QVariantMap ¶meters, QgsProcessingContext &context ) const
{
if ( !( flags() & FlagRequiresMatchingCrs ) )
{
// I'm a well behaved algorithm - I take work AWAY from users!
return true;
}
bool foundCrs = false;
QgsCoordinateReferenceSystem crs;
Q_FOREACH ( const QgsProcessingParameterDefinition *def, mParameters )
{
if ( def->type() == QStringLiteral( "layer" ) || def->type() == QStringLiteral( "raster" ) )
{
QgsMapLayer *layer = QgsProcessingParameters::parameterAsLayer( def, parameters, context );
if ( layer )
{
if ( foundCrs && layer->crs().isValid() && crs != layer->crs() )
{
return false;
}
else if ( !foundCrs && layer->crs().isValid() )
{
foundCrs = true;
crs = layer->crs();
}
}
}
else if ( def->type() == QStringLiteral( "source" ) )
{
QgsFeatureSource *source = QgsProcessingParameters::parameterAsSource( def, parameters, context );
if ( source )
{
if ( foundCrs && source->sourceCrs().isValid() && crs != source->sourceCrs() )
{
return false;
}
else if ( !foundCrs && source->sourceCrs().isValid() )
{
foundCrs = true;
crs = source->sourceCrs();
}
}
}
else if ( def->type() == QStringLiteral( "multilayer" ) )
{
QList< QgsMapLayer *> layers = QgsProcessingParameters::parameterAsLayerList( def, parameters, context );
Q_FOREACH ( QgsMapLayer *layer, layers )
{
if ( !layer )
continue;
if ( foundCrs && layer->crs().isValid() && crs != layer->crs() )
{
return false;
}
else if ( !foundCrs && layer->crs().isValid() )
{
foundCrs = true;
crs = layer->crs();
}
}
}
}