QGIS API Documentation 3.39.0-Master (bca3cdb6021)
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qgsalgorithmangletonearest.cpp
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1/***************************************************************************
2 qgsalgorithmangletonearest.cpp
3 ---------------------
4 begin : July 2020
5 copyright : (C) 2020 by Nyall Dawson
6 email : nyall dot dawson at gmail dot com
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
19#include "qgsspatialindex.h"
20#include "qgslinestring.h"
21#include "qgsvectorlayer.h"
22#include "qgsrenderer.h"
24#include "qgsmarkersymbol.h"
25
27
28class SetMarkerRotationVisitor : public QgsStyleEntityVisitorInterface
29{
30 public:
31
32 SetMarkerRotationVisitor( const QString &rotationField )
33 : mRotationField( rotationField )
34 {}
35
36 bool visit( const QgsStyleEntityVisitorInterface::StyleLeaf &entity ) override
37 {
38 if ( const QgsStyleSymbolEntity *symbolEntity = dynamic_cast< const QgsStyleSymbolEntity * >( entity.entity ) )
39 {
40 if ( QgsMarkerSymbol *marker = dynamic_cast< QgsMarkerSymbol * >( symbolEntity->symbol() ) )
41 {
42 marker->setDataDefinedAngle( QgsProperty::fromField( mRotationField ) );
43 }
44 }
45 return true;
46 }
47
48 private:
49 QString mRotationField;
50
51};
52
53class SetMarkerRotationPostProcessor : public QgsProcessingLayerPostProcessorInterface
54{
55 public:
56
57 SetMarkerRotationPostProcessor( std::unique_ptr< QgsFeatureRenderer > renderer, const QString &rotationField )
58 : mRenderer( std::move( renderer ) )
59 , mRotationField( rotationField )
60 {}
61
63 {
64 if ( QgsVectorLayer *vl = qobject_cast< QgsVectorLayer * >( layer ) )
65 {
66 SetMarkerRotationVisitor visitor( mRotationField );
67 mRenderer->accept( &visitor );
68 vl->setRenderer( mRenderer.release() );
69 vl->triggerRepaint();
70 }
71 }
72
73 private:
74
75 std::unique_ptr<QgsFeatureRenderer> mRenderer;
76 QString mRotationField;
77};
78
79QString QgsAngleToNearestAlgorithm::name() const
80{
81 return QStringLiteral( "angletonearest" );
82}
83
84QString QgsAngleToNearestAlgorithm::displayName() const
85{
86 return QObject::tr( "Align points to features" );
87}
88
89QStringList QgsAngleToNearestAlgorithm::tags() const
90{
91 return QObject::tr( "align,marker,stroke,fill,orient,points,lines,angles,rotation,rotate" ).split( ',' );
92}
93
94QString QgsAngleToNearestAlgorithm::group() const
95{
96 return QObject::tr( "Cartography" );
97}
98
99QString QgsAngleToNearestAlgorithm::groupId() const
100{
101 return QStringLiteral( "cartography" );
102}
103
104QgsAngleToNearestAlgorithm::~QgsAngleToNearestAlgorithm() = default;
105
106void QgsAngleToNearestAlgorithm::initAlgorithm( const QVariantMap &configuration )
107{
108 mIsInPlace = configuration.value( QStringLiteral( "IN_PLACE" ) ).toBool();
109
110 addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "INPUT" ),
111 QObject::tr( "Input layer" ), QList< int >() << static_cast< int >( Qgis::ProcessingSourceType::VectorPoint ) ) );
112 addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "REFERENCE_LAYER" ),
113 QObject::tr( "Reference layer" ) ) );
114
115 addParameter( new QgsProcessingParameterDistance( QStringLiteral( "MAX_DISTANCE" ),
116 QObject::tr( "Maximum distance to consider" ), QVariant(), QStringLiteral( "INPUT" ), true, 0 ) );
117
118 if ( !mIsInPlace )
119 addParameter( new QgsProcessingParameterString( QStringLiteral( "FIELD_NAME" ), QObject::tr( "Angle field name" ), QStringLiteral( "rotation" ) ) );
120 else
121 addParameter( new QgsProcessingParameterField( QStringLiteral( "FIELD_NAME" ), QObject::tr( "Angle field name" ), QStringLiteral( "rotation" ), QStringLiteral( "INPUT" ) ) );
122
123 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "APPLY_SYMBOLOGY" ), QObject::tr( "Automatically apply symbology" ), true ) );
124
125 addParameter( new QgsProcessingParameterFeatureSink( QStringLiteral( "OUTPUT" ), QObject::tr( "Aligned layer" ), Qgis::ProcessingSourceType::VectorPoint ) );
126}
127
128Qgis::ProcessingAlgorithmFlags QgsAngleToNearestAlgorithm::flags() const
129{
132 return f;
133}
134
135QString QgsAngleToNearestAlgorithm::shortHelpString() const
136{
137 return QObject::tr( "This algorithm calculates the rotation required to align point features with their nearest "
138 "feature from another reference layer. A new field is added to the output layer which is filled with the angle "
139 "(in degrees, clockwise) to the nearest reference feature.\n\n"
140 "Optionally, the output layer's symbology can be set to automatically use the calculated rotation "
141 "field to rotate marker symbols.\n\n"
142 "If desired, a maximum distance to use when aligning points can be set, to avoid aligning isolated points "
143 "to distant features." );
144}
145
146QString QgsAngleToNearestAlgorithm::shortDescription() const
147{
148 return QObject::tr( "Rotates point features to align them to nearby features." );
149}
150
151QgsAngleToNearestAlgorithm *QgsAngleToNearestAlgorithm::createInstance() const
152{
153 return new QgsAngleToNearestAlgorithm();
154}
155
156bool QgsAngleToNearestAlgorithm::supportInPlaceEdit( const QgsMapLayer *layer ) const
157{
158 if ( const QgsVectorLayer *vl = qobject_cast< const QgsVectorLayer * >( layer ) )
159 {
160 return vl->geometryType() == Qgis::GeometryType::Point;
161 }
162 return false;
163}
164
165bool QgsAngleToNearestAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
166{
167 if ( !mIsInPlace )
168 {
169 if ( QgsVectorLayer *sourceLayer = parameterAsVectorLayer( parameters, QStringLiteral( "INPUT" ), context ) )
170 {
171 mSourceRenderer.reset( sourceLayer->renderer()->clone() );
172 }
173 }
174
175 return true;
176}
177
178QVariantMap QgsAngleToNearestAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
179{
180 const double maxDistance = parameters.value( QStringLiteral( "MAX_DISTANCE" ) ).isValid() ? parameterAsDouble( parameters, QStringLiteral( "MAX_DISTANCE" ), context ) : std::numeric_limits< double >::quiet_NaN();
181 std::unique_ptr< QgsProcessingFeatureSource > input( parameterAsSource( parameters, QStringLiteral( "INPUT" ), context ) );
182 if ( !input )
183 throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "INPUT" ) ) );
184
185 std::unique_ptr< QgsProcessingFeatureSource > referenceSource( parameterAsSource( parameters, QStringLiteral( "REFERENCE_LAYER" ), context ) );
186 if ( !referenceSource )
187 throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "REFERENCE_LAYER" ) ) );
188
189 const QString fieldName = parameterAsString( parameters, QStringLiteral( "FIELD_NAME" ), context );
190
191 QgsFields outFields = input->fields();
192 int fieldIndex = -1;
193 if ( mIsInPlace )
194 {
195 fieldIndex = outFields.lookupField( fieldName );
196 }
197 else
198 {
199 outFields.append( QgsField( fieldName, QMetaType::Type::Double ) );
200 }
201
202 QString dest;
203 std::unique_ptr< QgsFeatureSink > sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, dest, outFields,
204 input->wkbType(), input->sourceCrs() ) );
205 if ( parameters.value( QStringLiteral( "OUTPUT" ) ).isValid() && !sink )
206 throw QgsProcessingException( invalidSinkError( parameters, QStringLiteral( "OUTPUT" ) ) );
207
208 // make spatial index
209 const QgsFeatureIterator f2 = referenceSource->getFeatures( QgsFeatureRequest().setDestinationCrs( input->sourceCrs(), context.transformContext() ).setNoAttributes() );
210 double step = referenceSource->featureCount() > 0 ? 50.0 / referenceSource->featureCount() : 1;
211 int i = 0;
212 const QgsSpatialIndex index( f2, [&]( const QgsFeature & )->bool
213 {
214 i++;
215 if ( feedback->isCanceled() )
216 return false;
217
218 feedback->setProgress( i * step );
219
220 return true;
222
223 QgsFeature f;
224
225 // Create output vector layer with additional attributes
226 step = input->featureCount() > 0 ? 50.0 / input->featureCount() : 1;
227 QgsFeatureIterator features = input->getFeatures();
228 i = 0;
229 while ( features.nextFeature( f ) )
230 {
231 i++;
232 if ( feedback->isCanceled() )
233 {
234 break;
235 }
236
237 feedback->setProgress( 50 + i * step );
238
239 QgsAttributes attributes = f.attributes();
240
241 if ( !f.hasGeometry() )
242 {
243 if ( !mIsInPlace )
244 attributes.append( QVariant() );
245 else
246 attributes[ fieldIndex ] = QVariant();
247 f.setAttributes( attributes );
248 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
249 throw QgsProcessingException( writeFeatureError( sink.get(), parameters, QStringLiteral( "OUTPUT" ) ) );
250 }
251 else
252 {
253 const QList< QgsFeatureId > nearest = index.nearestNeighbor( f.geometry(), 1, std::isnan( maxDistance ) ? 0 : maxDistance );
254 if ( nearest.empty() )
255 {
256 feedback->pushInfo( QObject::tr( "No matching features found within search distance" ) );
257 if ( !mIsInPlace )
258 attributes.append( QVariant() );
259 else
260 attributes[ fieldIndex ] = QVariant();
261 f.setAttributes( attributes );
262 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
263 throw QgsProcessingException( writeFeatureError( sink.get(), parameters, QStringLiteral( "OUTPUT" ) ) );
264 }
265 else
266 {
267 if ( nearest.count() > 1 )
268 {
269 feedback->pushInfo( QObject::tr( "Multiple matching features found at same distance from search feature, found %n feature(s)", nullptr, nearest.count() ) );
270 }
271
272 const QgsGeometry joinLine = f.geometry().shortestLine( index.geometry( nearest.at( 0 ) ) );
273 if ( const QgsLineString *line = qgsgeometry_cast< const QgsLineString * >( joinLine.constGet() ) )
274 {
275 if ( !mIsInPlace )
276 attributes.append( line->startPoint().azimuth( line->endPoint() ) );
277 else
278 attributes[ fieldIndex ] = line->startPoint().azimuth( line->endPoint() );
279 }
280 else
281 {
282 if ( !mIsInPlace )
283 attributes.append( QVariant() );
284 else
285 attributes[ fieldIndex ] = QVariant();
286 }
287 f.setAttributes( attributes );
288 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
289 throw QgsProcessingException( writeFeatureError( sink.get(), parameters, QStringLiteral( "OUTPUT" ) ) );
290 }
291 }
292 }
293
294 const bool applySymbology = parameterAsBool( parameters, QStringLiteral( "APPLY_SYMBOLOGY" ), context );
295 if ( applySymbology )
296 {
297 if ( mIsInPlace )
298 {
299 // get in place vector layer
300 // (possibly TODO - make this a reusable method!)
301 QVariantMap inPlaceParams = parameters;
302 inPlaceParams.insert( QStringLiteral( "INPUT" ), parameters.value( QStringLiteral( "INPUT" ) ).value< QgsProcessingFeatureSourceDefinition >().source );
303 if ( QgsVectorLayer *sourceLayer = parameterAsVectorLayer( inPlaceParams, QStringLiteral( "INPUT" ), context ) )
304 {
305 std::unique_ptr< QgsFeatureRenderer > sourceRenderer( sourceLayer->renderer()->clone() );
306 SetMarkerRotationPostProcessor processor( std::move( sourceRenderer ), fieldName );
307 processor.postProcessLayer( sourceLayer, context, feedback );
308 }
309 }
310 else if ( mSourceRenderer && context.willLoadLayerOnCompletion( dest ) )
311 {
312 context.layerToLoadOnCompletionDetails( dest ).setPostProcessor( new SetMarkerRotationPostProcessor( std::move( mSourceRenderer ), fieldName ) );
313 }
314 }
315
316 QVariantMap outputs;
317 outputs.insert( QStringLiteral( "OUTPUT" ), dest );
318 return outputs;
319}
320
321
@ VectorPoint
Vector point layers.
QFlags< ProcessingAlgorithmFlag > ProcessingAlgorithmFlags
Flags indicating how and when an algorithm operates and should be exposed to users.
Definition qgis.h:3319
@ SupportsInPlaceEdits
Algorithm supports in-place editing.
A vector of attributes.
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 & setNoAttributes()
Set that no attributes will be fetched.
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition qgsfeature.h:58
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:53
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:61
Encapsulate a field in an attribute table or data source.
Definition qgsfield.h:53
Container of fields for a vector layer.
Definition qgsfields.h:46
bool append(const QgsField &field, Qgis::FieldOrigin origin=Qgis::FieldOrigin::Provider, int originIndex=-1)
Appends a field.
Definition qgsfields.cpp:69
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.
const QgsAbstractGeometry * constGet() const
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
QgsGeometry shortestLine(const QgsGeometry &other) const
Returns the shortest line joining this geometry to another geometry.
Line string geometry type, with support for z-dimension and m-values.
Base class for all map layer types.
Definition qgsmaplayer.h:76
A marker symbol type, for rendering Point and MultiPoint geometries.
virtual Qgis::ProcessingAlgorithmFlags flags() const
Returns the flags indicating how and when the algorithm operates and should be exposed to users.
void setPostProcessor(QgsProcessingLayerPostProcessorInterface *processor)
Sets the layer post-processor.
Contains information about the context in which a processing algorithm is executed.
QgsProcessingContext::LayerDetails & layerToLoadOnCompletionDetails(const QString &layer)
Returns a reference to the details for a given layer which is loaded on completion of the algorithm o...
QgsCoordinateTransformContext transformContext() const
Returns the coordinate transform context.
bool willLoadLayerOnCompletion(const QString &layer) const
Returns true if the given layer (by ID or datasource) will be loaded into the current project upon co...
Custom exception class for processing related exceptions.
Base class for providing feedback from a processing algorithm.
virtual void pushInfo(const QString &info)
Pushes a general informational message from the algorithm.
An interface for layer post-processing handlers for execution following a processing algorithm operat...
virtual void postProcessLayer(QgsMapLayer *layer, QgsProcessingContext &context, QgsProcessingFeedback *feedback)=0
Post-processes the specified layer, following successful execution of a processing algorithm.
A boolean parameter for processing algorithms.
A double numeric parameter for distance values.
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.
A string parameter for processing algorithms.
static QgsProperty fromField(const QString &fieldName, bool isActive=true)
Returns a new FieldBasedProperty created from the specified field name.
A spatial index for QgsFeature objects.
@ FlagStoreFeatureGeometries
Indicates that the spatial index should also store feature geometries. This requires more memory,...
An interface for classes which can visit style entity (e.g.
virtual bool visit(const QgsStyleEntityVisitorInterface::StyleLeaf &entity)
Called when the visitor will visit a style entity.
A symbol entity for QgsStyle databases.
Definition qgsstyle.h:1396
Represents a vector layer which manages a vector based data sets.
Contains information relating to the style entity currently being visited.
const QgsStyleEntityInterface * entity
Reference to style entity being visited.