QGIS API Documentation  3.16.0-Hannover (43b64b13f3)
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 
QgsProcessingAlgorithm::shortDescription
virtual QString shortDescription() const
Returns an optional translated short description of the algorithm.
Definition: qgsprocessingalgorithm.cpp:58
QgsProcessingAlgorithm::displayName
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
QgsProcessingFeedback
Base class for providing feedback from a processing algorithm.
Definition: qgsprocessingfeedback.h:38
qgsfeature.h
qgis.h
QgsProcessingAlgorithm::groupId
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:233
QgsProcessingAlgorithm::createInstance
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
QgsAttributeList
QList< int > QgsAttributeList
Definition: qgsfield.h:26
SIP_FACTORY
#define SIP_FACTORY
Definition: qgis_sip.h:76
QgsProcessingAlgorithm::name
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
QgsProcessingAlgorithm::processAlgorithm
virtual QVariantMap processAlgorithm(const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)=0
Runs the algorithm using the specified parameters.
QgsProcessingContext
Contains information about the context in which a processing algorithm is executed.
Definition: qgsprocessingcontext.h:44
qgsprocessingalgorithm.h
QgsProcessingAlgorithm::shortHelpString
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.
Definition: qgsprocessingalgorithm.cpp:63
QgsFeatureIds
QSet< QgsFeatureId > QgsFeatureIds
Definition: qgsfeatureid.h:37
QgsProcessingAlgorithm
Abstract base class for processing algorithms.
Definition: qgsprocessingalgorithm.h:52
QgsProcessingAlgorithm::group
virtual QString group() const
Returns the name of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:224
QgsFeature
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:56
QgsGeometryEngine
Contains geometry relation and modification algorithms.
Definition: qgsgeometryengine.h:35
QgsProcessingAlgorithm::tags
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
Definition: qgsprocessingalgorithm.h:180
QgsProcessingAlgorithm::initAlgorithm
virtual void initAlgorithm(const QVariantMap &configuration=QVariantMap())=0
Initializes the algorithm using the specified configuration.