25QString QgsJoinWithLinesAlgorithm::name()
const
27 return QStringLiteral(
"hublines" );
30QString QgsJoinWithLinesAlgorithm::displayName()
const
32 return QObject::tr(
"Join by lines (hub lines)" );
35QStringList QgsJoinWithLinesAlgorithm::tags()
const
37 return QObject::tr(
"join,connect,lines,points,hub,spoke,geodesic,great,circle" ).split(
',' );
40QString QgsJoinWithLinesAlgorithm::group()
const
42 return QObject::tr(
"Vector analysis" );
45QString QgsJoinWithLinesAlgorithm::groupId()
const
47 return QStringLiteral(
"vectoranalysis" );
50void QgsJoinWithLinesAlgorithm::initAlgorithm(
const QVariantMap & )
53 QObject::tr(
"Hub layer" ) ) );
55 QObject::tr(
"Hub ID field" ), QVariant(), QStringLiteral(
"HUBS" ) ) );
58 QObject::tr(
"Hub layer fields to copy (leave empty to copy all fields)" ),
63 QObject::tr(
"Spoke layer" ) ) );
65 QObject::tr(
"Spoke ID field" ), QVariant(), QStringLiteral(
"SPOKES" ) ) );
68 QObject::tr(
"Spoke layer fields to copy (leave empty to copy all fields)" ),
74 auto distanceParam = std::make_unique< QgsProcessingParameterDistance >( QStringLiteral(
"GEODESIC_DISTANCE" ), QObject::tr(
"Distance between vertices (geodesic lines only)" ), 1000 );
77 distanceParam->setIsDynamic(
true );
79 distanceParam->setDynamicLayerParameterName( QStringLiteral(
"HUBS" ) );
80 addParameter( distanceParam.release() );
82 auto breakParam = std::make_unique< QgsProcessingParameterBoolean >( QStringLiteral(
"ANTIMERIDIAN_SPLIT" ), QObject::tr(
"Split lines at antimeridian (±180 degrees longitude)" ),
false );
84 addParameter( breakParam.release() );
89QString QgsJoinWithLinesAlgorithm::shortHelpString()
const
91 return QObject::tr(
"This algorithm creates hub and spoke diagrams by connecting lines from points on the Spoke layer to matching points in the Hub layer.\n\n"
92 "Determination of which hub goes with each point is based on a match between the Hub ID field on the hub points and the Spoke ID field on the spoke points.\n\n"
93 "If input layers are not point layers, a point on the surface of the geometries will be taken as the connecting location.\n\n"
94 "Optionally, geodesic lines can be created, which represent the shortest path on the surface of an ellipsoid. When "
95 "geodesic mode is used, it is possible to split the created lines at the antimeridian (±180 degrees longitude), which can improve "
96 "rendering of the lines. Additionally, the distance between vertices can be specified. A smaller distance results in a denser, more "
100QString QgsJoinWithLinesAlgorithm::shortDescription()
const
102 return QObject::tr(
"Creates lines joining two point layers, based on a common attribute value." );
110QgsJoinWithLinesAlgorithm *QgsJoinWithLinesAlgorithm::createInstance()
const
112 return new QgsJoinWithLinesAlgorithm();
117 if ( parameters.value( QStringLiteral(
"SPOKES" ) ) == parameters.value( QStringLiteral(
"HUBS" ) ) )
120 std::unique_ptr< QgsProcessingFeatureSource > hubSource( parameterAsSource( parameters, QStringLiteral(
"HUBS" ), context ) );
124 std::unique_ptr< QgsProcessingFeatureSource > spokeSource( parameterAsSource( parameters, QStringLiteral(
"SPOKES" ), context ) );
128 const QString fieldHubName = parameterAsString( parameters, QStringLiteral(
"HUB_FIELD" ), context );
129 const int fieldHubIndex = hubSource->fields().lookupField( fieldHubName );
130 const QStringList hubFieldsToCopy = parameterAsStrings( parameters, QStringLiteral(
"HUB_FIELDS" ), context );
132 const QString fieldSpokeName = parameterAsString( parameters, QStringLiteral(
"SPOKE_FIELD" ), context );
133 const int fieldSpokeIndex = spokeSource->fields().lookupField( fieldSpokeName );
134 const QStringList spokeFieldsToCopy = parameterAsStrings( parameters, QStringLiteral(
"SPOKE_FIELDS" ), context );
136 if ( fieldHubIndex < 0 || fieldSpokeIndex < 0 )
139 const bool geodesic = parameterAsBoolean( parameters, QStringLiteral(
"GEODESIC" ), context );
140 const double geodesicDistance = parameterAsDouble( parameters, QStringLiteral(
"GEODESIC_DISTANCE" ), context ) * 1000;
142 QgsExpressionContext expressionContext = createExpressionContext( parameters, context, hubSource.get() );
144 if ( dynamicGeodesicDistance )
146 geodesicDistanceProperty = parameters.
value( QStringLiteral(
"GEODESIC_DISTANCE" ) ).value<
QgsProperty >();
149 const bool splitAntimeridian = parameterAsBoolean( parameters, QStringLiteral(
"ANTIMERIDIAN_SPLIT" ), context );
156 if ( hubFieldsToCopy.empty() )
158 hubOutFields = hubSource->fields();
159 hubFieldIndices.reserve( hubOutFields.
count() );
160 for (
int i = 0; i < hubOutFields.
count(); ++i )
162 hubFieldIndices << i;
167 hubFieldIndices.reserve( hubOutFields.
count() );
168 for (
const QString &field : hubFieldsToCopy )
170 const int index = hubSource->fields().
lookupField( field );
173 hubFieldIndices << index;
174 hubOutFields.
append( hubSource->fields().at( index ) );
180 hubFields2Fetch << fieldHubIndex;
184 if ( spokeFieldsToCopy.empty() )
186 spokeOutFields = spokeSource->fields();
187 spokeFieldIndices.reserve( spokeOutFields.
count() );
188 for (
int i = 0; i < spokeOutFields.
count(); ++i )
190 spokeFieldIndices << i;
195 for (
const QString &field : spokeFieldsToCopy )
197 const int index = spokeSource->fields().
lookupField( field );
200 spokeFieldIndices << index;
201 spokeOutFields.
append( spokeSource->fields().at( index ) );
207 spokeFields2Fetch << fieldSpokeIndex;
227 std::unique_ptr< QgsFeatureSink > sink( parameterAsSink( parameters, QStringLiteral(
"OUTPUT" ), context, dest, fields,
236 p = *
static_cast< const QgsPoint *
>( feature.geometry().constGet() );
238 p = *
static_cast< const QgsPoint *
>( feature.geometry().pointOnSurface().constGet() );
239 if ( hasZ && !p.
is3D() )
247 const double step = hubSource->featureCount() > 0 ? 100.0 / hubSource->featureCount() : 1;
263 const QgsPoint hubPoint = getPointFromFeature( hubFeature );
268 for (
int j = 0; j < attributeCount; ++j )
270 if ( !hubFieldIndices.contains( j ) )
272 hubAttributes << hubFeature.
attribute( j );
281 while ( spokeFeatures.
nextFeature( spokeFeature ) )
290 const QgsPoint spokePoint = getPointFromFeature( spokeFeature );
295 if ( splitAntimeridian )
300 double distance = geodesicDistance;
301 if ( dynamicGeodesicDistance )
304 distance = geodesicDistanceProperty.
valueAsDouble( expressionContext, distance );
307 std::unique_ptr< QgsMultiLineString > ml = std::make_unique< QgsMultiLineString >();
308 std::unique_ptr< QgsLineString > l = std::make_unique< QgsLineString >( QVector< QgsPoint >() << hubPoint );
310 QVector< QgsPointXY > points1 = points.at( 0 );
312 if ( points.count() == 1 )
316 l->append( &geodesicPoints );
317 if ( points.count() == 1 )
318 l->addVertex( spokePoint );
320 ml->addGeometry( l.release() );
321 if ( points.count() > 1 )
323 QVector< QgsPointXY > points2 = points.at( 1 );
325 l = std::make_unique< QgsLineString >( points2 );
327 l->addZValue( std::numeric_limits<double>::quiet_NaN() );
329 l->addMValue( std::numeric_limits<double>::quiet_NaN() );
331 l->addVertex( spokePoint );
332 ml->addGeometry( l.release() );
343 for (
int j = 0; j < attributeCount; ++j )
345 if ( !spokeFieldIndices.contains( j ) )
347 spokeAttributes << spokeFeature.
attribute( j );
350 outAttributes.append( spokeAttributes );
359 outputs.insert( QStringLiteral(
"OUTPUT" ), dest );
@ VectorLine
Vector line layers.
@ RegeneratesPrimaryKey
Algorithm always drops any existing primary keys or FID values and regenerates them in outputs.
QFlags< ProcessingAlgorithmDocumentationFlag > ProcessingAlgorithmDocumentationFlags
Flags describing algorithm behavior for documentation purposes.
@ SkipGeometryValidityChecks
Invalid geometry checks should always be skipped. This flag can be useful for algorithms which always...
WkbType
The WKB type describes the number of dimensions a geometry has.
@ MultiLineString
MultiLineString.
@ Advanced
Parameter is an advanced parameter which should be hidden from users by default.
bool isMeasure() const
Returns true if the geometry contains m values.
bool is3D() const
Returns true if the geometry is 3D and contains a z-value.
A general purpose distance and area calculator, capable of performing ellipsoid based calculations.
QVector< QVector< QgsPointXY > > geodesicLine(const QgsPointXY &p1, const QgsPointXY &p2, double interval, bool breakLine=false) const
Calculates the geodesic line between p1 and p2, which represents the shortest path on the ellipsoid b...
void setSourceCrs(const QgsCoordinateReferenceSystem &crs, const QgsCoordinateTransformContext &context)
Sets source spatial reference system crs.
QgsGeometry splitGeometryAtAntimeridian(const QgsGeometry &geometry) const
Splits a (Multi)LineString geometry at the antimeridian (longitude +/- 180 degrees).
bool setEllipsoid(const QString &ellipsoid)
Sets the ellipsoid by its acronym.
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.
static QString createFieldEqualityExpression(const QString &fieldName, const QVariant &value, QMetaType::Type fieldType=QMetaType::Type::UnknownType)
Create an expression allowing to evaluate if a field is equal to a value.
Wrapper for iterator of features from vector data provider or vector layer.
bool nextFeature(QgsFeature &f)
Fetch next feature and stores in f, returns true on success.
This class wraps a request for features to a vector layer (or directly its vector data provider).
QgsFeatureRequest & setSubsetOfAttributes(const QgsAttributeList &attrs)
Set a subset of attributes that will be fetched.
QgsFeatureRequest & setDestinationCrs(const QgsCoordinateReferenceSystem &crs, const QgsCoordinateTransformContext &context)
Sets the destination crs for feature's geometries.
QgsFeatureRequest & setFilterExpression(const QString &expression)
Set the filter expression.
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
@ RegeneratePrimaryKey
This flag indicates, that a primary key field cannot be guaranteed to be unique and the sink should i...
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
void setAttributes(const QgsAttributes &attrs)
Sets the feature's attributes.
int attributeCount() const
Returns the number of attributes attached to the feature.
bool hasGeometry() const
Returns true if the feature has an associated geometry.
Q_INVOKABLE QVariant attribute(const QString &name) const
Lookup attribute value by attribute name.
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
bool isCanceled() const
Tells whether the operation has been canceled already.
void setProgress(double progress)
Sets the current progress for the feedback object.
Container of fields for a vector layer.
bool append(const QgsField &field, Qgis::FieldOrigin origin=Qgis::FieldOrigin::Provider, int originIndex=-1)
Appends a field.
Q_INVOKABLE int lookupField(const QString &fieldName) const
Looks up field's index from the field name.
A geometry is the spatial representation of a feature.
Line string geometry type, with support for z-dimension and m-values.
A class to represent a 2D point.
Point geometry type, with support for z-dimension and m-values.
bool addMValue(double mValue=0) override
Adds a measure to the geometry, initialized to a preset value.
bool addZValue(double zValue=0) override
Adds a z-dimension to the geometry, initialized to a preset value.
Contains information about the context in which a processing algorithm is executed.
QgsCoordinateTransformContext transformContext() const
Returns the coordinate transform context.
QString ellipsoid() const
Returns the ellipsoid to use for distance and area calculations.
Custom exception class for processing related exceptions.
Base class for providing feedback from a processing algorithm.
A boolean parameter for processing algorithms.
A feature sink output for processing algorithms.
An input feature source (such as vector layers) parameter for processing algorithms.
A vector layer or feature source field parameter for processing algorithms.
static bool isDynamic(const QVariantMap ¶meters, const QString &name)
Returns true if the parameter with matching name is a dynamic parameter, and must be evaluated once f...
static QgsFields combineFields(const QgsFields &fieldsA, const QgsFields &fieldsB, const QString &fieldsBPrefix=QString())
Combines two field lists, avoiding duplicate field names (in a case-insensitive manner).
Definition for a property.
@ DoublePositive
Positive double value (including 0)
A store for object properties.
QVariant value(const QgsExpressionContext &context, const QVariant &defaultValue=QVariant(), bool *ok=nullptr) const
Calculates the current value of the property, including any transforms which are set for the property...
double valueAsDouble(const QgsExpressionContext &context, double defaultValue=0.0, bool *ok=nullptr) const
Calculates the current value of the property and interprets it as a double.
static Qgis::WkbType addM(Qgis::WkbType type)
Adds the m dimension to a WKB type and returns the new type.
static Qgis::WkbType addZ(Qgis::WkbType type)
Adds the z dimension to a WKB type and returns the new type.
static bool hasZ(Qgis::WkbType type)
Tests whether a WKB type contains the z-dimension.
static bool hasM(Qgis::WkbType type)
Tests whether a WKB type contains m values.
QList< int > QgsAttributeList