QVariantMap QgsJoinWithLinesAlgorithm::processAlgorithm( const QVariantMap ¶meters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
{
if ( parameters.value( QStringLiteral( "SPOKES" ) ) == parameters.value( QStringLiteral( "HUBS" ) ) )
throw QgsProcessingException( QObject::tr( "Same layer given for both hubs and spokes" ) );
std::unique_ptr< QgsProcessingFeatureSource > hubSource( parameterAsSource( parameters, QStringLiteral( "HUBS" ), context ) );
if ( !hubSource )
throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "HUBS" ) ) );
std::unique_ptr< QgsProcessingFeatureSource > spokeSource( parameterAsSource( parameters, QStringLiteral( "SPOKES" ), context ) );
if ( !hubSource || !spokeSource )
throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "SPOKES" ) ) );
QString fieldHubName = parameterAsString( parameters, QStringLiteral( "HUB_FIELD" ), context );
int fieldHubIndex = hubSource->fields().lookupField( fieldHubName );
const QStringList hubFieldsToCopy = parameterAsFields( parameters, QStringLiteral( "HUB_FIELDS" ), context );
QString fieldSpokeName = parameterAsString( parameters, QStringLiteral( "SPOKE_FIELD" ), context );
int fieldSpokeIndex = spokeSource->fields().lookupField( fieldSpokeName );
const QStringList spokeFieldsToCopy = parameterAsFields( parameters, QStringLiteral( "SPOKE_FIELDS" ), context );
if ( fieldHubIndex < 0 || fieldSpokeIndex < 0 )
throw QgsProcessingException( QObject::tr( "Invalid ID field" ) );
const bool geodesic = parameterAsBool( parameters, QStringLiteral( "GEODESIC" ), context );
const double geodesicDistance = parameterAsDouble( parameters, QStringLiteral( "GEODESIC_DISTANCE" ), context ) * 1000;
bool dynamicGeodesicDistance = QgsProcessingParameters::isDynamic( parameters, QStringLiteral( "GEODESIC_DISTANCE" ) );
QgsExpressionContext expressionContext = createExpressionContext( parameters, context, hubSource.get() );
QgsProperty geodesicDistanceProperty;
if ( dynamicGeodesicDistance )
{
geodesicDistanceProperty = parameters.value( QStringLiteral( "GEODESIC_DISTANCE" ) ).value< QgsProperty >();
}
const bool splitAntimeridian = parameterAsBool( parameters, QStringLiteral( "ANTIMERIDIAN_SPLIT" ), context );
QgsDistanceArea da;
da.setSourceCrs( hubSource->sourceCrs(), context.transformContext() );
da.setEllipsoid( context.project()->ellipsoid() );
QgsFields hubOutFields;
QgsAttributeList hubFieldIndices;
if ( hubFieldsToCopy.empty() )
{
hubOutFields = hubSource->fields();
hubFieldIndices.reserve( hubOutFields.count() );
for ( int i = 0; i < hubOutFields.count(); ++i )
{
hubFieldIndices << i;
}
}
else
{
hubFieldIndices.reserve( hubOutFields.count() );
for ( const QString &field : hubFieldsToCopy )
{
int index = hubSource->fields().lookupField( field );
if ( index >= 0 )
{
hubFieldIndices << index;
hubOutFields.append( hubSource->fields().at( index ) );
}
}
}
QgsAttributeList hubFields2Fetch = hubFieldIndices;
hubFields2Fetch << fieldHubIndex;
QgsFields spokeOutFields;
QgsAttributeList spokeFieldIndices;
if ( spokeFieldsToCopy.empty() )
{
spokeOutFields = spokeSource->fields();
spokeFieldIndices.reserve( spokeOutFields.count() );
for ( int i = 0; i < spokeOutFields.count(); ++i )
{
spokeFieldIndices << i;
}
}
else
{
for ( const QString &field : spokeFieldsToCopy )
{
int index = spokeSource->fields().lookupField( field );
if ( index >= 0 )
{
spokeFieldIndices << index;
spokeOutFields.append( spokeSource->fields().at( index ) );
}
}
}
QgsAttributeList spokeFields2Fetch = spokeFieldIndices;
spokeFields2Fetch << fieldSpokeIndex;
QgsFields fields = QgsProcessingUtils::combineFields( hubOutFields, spokeOutFields );
QgsWkbTypes::Type outType = geodesic ? QgsWkbTypes::MultiLineString : QgsWkbTypes::LineString;
bool hasZ = false;
if ( QgsWkbTypes::hasZ( hubSource->wkbType() ) || QgsWkbTypes::hasZ( spokeSource->wkbType() ) )
{
outType = QgsWkbTypes::addZ( outType );
hasZ = true;
}
bool hasM = false;
if ( QgsWkbTypes::hasM( hubSource->wkbType() ) || QgsWkbTypes::hasM( spokeSource->wkbType() ) )
{
outType = QgsWkbTypes::addM( outType );
hasM = true;
}
QString dest;
std::unique_ptr< QgsFeatureSink > sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, dest, fields,
outType, hubSource->sourceCrs(), QgsFeatureSink::RegeneratePrimaryKey ) );
if ( !sink )
throw QgsProcessingException( invalidSinkError( parameters, QStringLiteral( "OUTPUT" ) ) );
auto getPointFromFeature = [hasZ, hasM]( const QgsFeature & feature )->QgsPoint
{
QgsPoint p;
if ( feature.geometry().type() == QgsWkbTypes::PointGeometry && !feature.geometry().isMultipart() )
p = *static_cast< const QgsPoint *>( feature.geometry().constGet() );
else
p = *static_cast< const QgsPoint *>( feature.geometry().pointOnSurface().constGet() );
if ( hasZ && !p.is3D() )
p.addZValue( 0 );
if ( hasM && !p.isMeasure() )
p.addMValue( 0 );
return p;
};
QgsFeatureIterator hubFeatures = hubSource->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( hubFields2Fetch ), QgsProcessingFeatureSource::FlagSkipGeometryValidityChecks );
double step = hubSource->featureCount() > 0 ? 100.0 / hubSource->featureCount() : 1;
int i = 0;
QgsFeature hubFeature;
while ( hubFeatures.nextFeature( hubFeature ) )
{
i++;
if ( feedback->isCanceled() )
{
break;
}
feedback->setProgress( i * step );
if ( !hubFeature.hasGeometry() )
continue;
QgsPoint hubPoint = getPointFromFeature( hubFeature );
// only keep selected attributes
QgsAttributes hubAttributes;
for ( int j = 0; j < hubFeature.attributes().count(); ++j )
{
if ( !hubFieldIndices.contains( j ) )
continue;
hubAttributes << hubFeature.attribute( j );
}
QgsFeatureRequest spokeRequest = QgsFeatureRequest().setDestinationCrs( hubSource->sourceCrs(), context.transformContext() );
spokeRequest.setSubsetOfAttributes( spokeFields2Fetch );
spokeRequest.setFilterExpression( QgsExpression::createFieldEqualityExpression( fieldSpokeName, hubFeature.attribute( fieldHubIndex ) ) );
QgsFeatureIterator spokeFeatures = spokeSource->getFeatures( spokeRequest, QgsProcessingFeatureSource::FlagSkipGeometryValidityChecks );
QgsFeature spokeFeature;
while ( spokeFeatures.nextFeature( spokeFeature ) )
{
if ( feedback->isCanceled() )
{
break;
}
if ( !spokeFeature.hasGeometry() )
continue;
QgsPoint spokePoint = getPointFromFeature( spokeFeature );
QgsGeometry line;
if ( !geodesic )
{
line = QgsGeometry( new QgsLineString( QVector< QgsPoint >() << hubPoint << spokePoint ) );
if ( splitAntimeridian )
line = da.splitGeometryAtAntimeridian( line );
}
else
{
double distance = geodesicDistance;
if ( dynamicGeodesicDistance )
{
expressionContext.setFeature( hubFeature );
distance = geodesicDistanceProperty.valueAsDouble( expressionContext, distance );
}
std::unique_ptr< QgsMultiLineString > ml = qgis::make_unique< QgsMultiLineString >();
std::unique_ptr< QgsLineString > l = qgis::make_unique< QgsLineString >( QVector< QgsPoint >() << hubPoint );
QVector< QVector< QgsPointXY > > points = da.geodesicLine( QgsPointXY( hubPoint ), QgsPointXY( spokePoint ), distance, splitAntimeridian );
QVector< QgsPointXY > points1 = points.at( 0 );
points1.pop_front();
if ( points.count() == 1 )
points1.pop_back();
QgsLineString geodesicPoints( points1 );
l->append( &geodesicPoints );
if ( points.count() == 1 )
l->addVertex( spokePoint );
ml->addGeometry( l.release() );
if ( points.count() > 1 )
{
QVector< QgsPointXY > points2 = points.at( 1 );
points2.pop_back();
l = qgis::make_unique< QgsLineString >( points2 );
if ( hasZ )
l->addZValue( std::numeric_limits<double>::quiet_NaN() );
if ( hasM )
l->addMValue( std::numeric_limits<double>::quiet_NaN() );
l->addVertex( spokePoint );
ml->addGeometry( l.release() );
}
line = QgsGeometry( std::move( ml ) );
}
QgsFeature outFeature;
QgsAttributes outAttributes = hubAttributes;
// only keep selected attributes
QgsAttributes spokeAttributes;
for ( int j = 0; j < spokeFeature.attributes().count(); ++j )
{
if ( !spokeFieldIndices.contains( j ) )
continue;
spokeAttributes << spokeFeature.attribute( j );
}
outAttributes.append( spokeAttributes );
outFeature.setAttributes( outAttributes );
outFeature.setGeometry( line );
sink->addFeature( outFeature, QgsFeatureSink::FastInsert );
}
}
QVariantMap outputs;
outputs.insert( QStringLiteral( "OUTPUT" ), dest );
return outputs;
}
