QGIS API Documentation  3.17.0-Master (ca637cfeb2)
qgsalgorithmjoinbylocation.h
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1 /***************************************************************************
2  qgsalgorithmjoinbylocation.h
3  ---------------------
4  begin : January 2020
5  copyright : (C) 2020 by Alexis Roy-Lizotte
6  email : roya2 at premiertech 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 
18 #ifndef QGSALGORITHMJOINBYLOCATION_H
19 #define QGSALGORITHMJOINBYLOCATION_H
20 
21 #define SIP_NO_FILE
22 
23 #include "qgis.h"
24 #include "qgsprocessingalgorithm.h"
25 #include "qgsfeature.h"
26 
27 
29 
35 class QgsJoinByLocationAlgorithm : public QgsProcessingAlgorithm
36 {
37 
38  public:
39 
40  QgsJoinByLocationAlgorithm() = default;
41  void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) override;
42  QString name() const override;
43  QString displayName() const override;
44  QStringList tags() const override;
45  QString group() const override;
46  QString groupId() const override;
47  QString shortHelpString() const override;
48  QString shortDescription() const override;
49  QgsJoinByLocationAlgorithm *createInstance() const override SIP_FACTORY;
50 
51  protected:
52  QVariantMap processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
53  bool processFeatureFromJoinSource( QgsFeature &joinFeature, QgsProcessingFeedback *feedback );
54  bool processFeatureFromInputSource( QgsFeature &inputFeature, QgsProcessingContext &context, QgsProcessingFeedback *feedback );
55  bool featureFilter( const QgsFeature &feature, QgsGeometryEngine *engine, bool comparingToJoinedFeature ) const;
56 
57  private:
58 
59  void processAlgorithmByIteratingOverJoinedSource( QgsProcessingContext &context, QgsProcessingFeedback *feedback );
60  void processAlgorithmByIteratingOverInputSource( QgsProcessingContext &context, QgsProcessingFeedback *feedback );
61 
62  enum JoinMethod
63  {
64  OneToMany = 0,
65  JoinToFirst = 1,
66  JoinToLargestOverlap = 2
67  };
68  long mJoinedCount = 0;
69  std::unique_ptr< QgsProcessingFeatureSource > mBaseSource;
70  std::unique_ptr< QgsProcessingFeatureSource > mJoinSource;
71  QgsAttributeList mJoinedFieldIndices;
72  bool mDiscardNonMatching = false;
73  std::unique_ptr< QgsFeatureSink > mJoinedFeatures;
74  QgsFeatureIds mAddedIds;
75  std::unique_ptr< QgsFeatureSink > mUnjoinedFeatures;
76  JoinMethod mJoinMethod = OneToMany;
77  QList<int> mPredicates;
78 
79  static void sortPredicates( QList<int > &predicates );
80 };
81 
83 
84 #endif // QGSALGORITHMJOINBYLOCATION_H
85 
86 
QSet< QgsFeatureId > QgsFeatureIds
Definition: qgsfeatureid.h:37
Base class for providing feedback from a processing algorithm.
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
virtual QString group() const
Returns the name of the group this algorithm belongs to.
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:55
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.
Abstract base class for processing algorithms.
virtual void initAlgorithm(const QVariantMap &configuration=QVariantMap())=0
Initializes the algorithm using the specified configuration.
#define SIP_FACTORY
Definition: qgis_sip.h:76
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
virtual QVariantMap processAlgorithm(const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)=0
Runs the algorithm using the specified parameters.
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
virtual QString shortDescription() const
Returns an optional translated short description of the algorithm.
Contains geometry relation and modification algorithms.
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
QList< int > QgsAttributeList
Definition: qgsfield.h:26
Contains information about the context in which a processing algorithm is executed.