QGIS API Documentation 3.27.0-Master (1d7a28cfd2)
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2 qgsalgorithmsumlinelength.h
3 ---------------------
4 begin : November 2019
5 copyright : (C) 2019 by Alexander Bruy
6 email : alexander dot bruy at gmail dot com
7 ***************************************************************************/
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 ***************************************************************************/
21#define SIP_NO_FILE
23#include "qgis.h"
25#include "qgsdistancearea.h"
31class QgsSumLineLengthAlgorithm : public QgsProcessingFeatureBasedAlgorithm
34 public:
36 QgsSumLineLengthAlgorithm() = default;
37 QString name() const override;
38 QString displayName() const override;
39 QStringList tags() const override;
40 QString svgIconPath() const override;
41 QIcon icon() const override;
42 QString group() const override;
43 QString groupId() const override;
44 QString shortHelpString() const override;
45 QgsSumLineLengthAlgorithm *createInstance() const override SIP_FACTORY;
46 void initParameters( const QVariantMap &configuration = QVariantMap() ) override;
47 QList<int> inputLayerTypes() const override;
48 QgsProcessing::SourceType outputLayerType() const override;
52 protected:
53 QString inputParameterName() const override;
54 QString inputParameterDescription() const override;
55 QString outputName() const override;
56 bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
57 QgsFeatureList processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
58 QgsFields outputFields( const QgsFields &inputFields ) const override;
59 bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
61 private:
62 bool mIsInPlace = false;
63 QString mLengthFieldName;
64 QString mCountFieldName;
65 mutable int mLengthFieldIndex = -1;
66 mutable int mCountFieldIndex = -1;
67 mutable QgsFields mFields;
69 mutable QgsDistanceArea mDa;
70 QgsCoordinateTransformContext mTransformContext;
71 std::unique_ptr< QgsProcessingFeatureSource > mLinesSource;
This class represents a coordinate reference system (CRS).
Contains information about the context in which a coordinate transform is executed.
A general purpose distance and area calculator, capable of performing ellipsoid based calculations.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
Container of fields for a vector layer.
Definition: qgsfields.h:45
Base class for all map layer types.
Definition: qgsmaplayer.h:73
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
virtual QString group() const
Returns the name of the group this algorithm belongs to.
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
virtual QIcon icon() const
Returns an icon for the algorithm.
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
virtual QString svgIconPath() const
Returns a path to an SVG version of the algorithm's icon.
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
Contains information about the context in which a processing algorithm is executed.
An abstract QgsProcessingAlgorithm base class for processing algorithms which operate "feature-by-fea...
Base class for providing feedback from a processing algorithm.
Data source types enum.
Definition: qgsprocessing.h:46
Definition: qgis_sip.h:76
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:922
const QgsCoordinateReferenceSystem & outputCrs