QGIS API Documentation 3.39.0-Master (67e056379ed)
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qgsalgorithmspatialindex.cpp
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1/***************************************************************************
2 qgsalgorithmspatialindex.cpp
3 ---------------------
4 begin : November 2019
5 copyright : (C) 2019 by Alexander Bruy
6 email : alexander dot bruy 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 "qgsvectorlayer.h"
21
23
24QString QgsSpatialIndexAlgorithm::name() const
25{
26 return QStringLiteral( "createspatialindex" );
27}
28
29QString QgsSpatialIndexAlgorithm::displayName() const
30{
31 return QObject::tr( "Create spatial index" );
32}
33
34QStringList QgsSpatialIndexAlgorithm::tags() const
35{
36 return QObject::tr( "table,spatial,geometry,index,create,vector" ).split( ',' );
37}
38
39QString QgsSpatialIndexAlgorithm::group() const
40{
41 return QObject::tr( "Vector general" );
42}
43
44QString QgsSpatialIndexAlgorithm::groupId() const
45{
46 return QStringLiteral( "vectorgeneral" );
47}
48
49Qgis::ProcessingAlgorithmFlags QgsSpatialIndexAlgorithm::flags() const
50{
52}
53
54
55QString QgsSpatialIndexAlgorithm::shortHelpString() const
56{
57 return QObject::tr( "Creates an index to speed up access to the features "
58 "in a layer based on their spatial location. Support "
59 "for spatial index creation is dependent on the layer's "
60 "data provider." );
61}
62
63QgsSpatialIndexAlgorithm *QgsSpatialIndexAlgorithm::createInstance() const
64{
65 return new QgsSpatialIndexAlgorithm();
66}
67
68void QgsSpatialIndexAlgorithm::initAlgorithm( const QVariantMap & )
69{
70 addParameter( new QgsProcessingParameterVectorLayer( QStringLiteral( "INPUT" ), QObject::tr( "Input layer" ) ) );
71
72 addOutput( new QgsProcessingOutputVectorLayer( QStringLiteral( "OUTPUT" ), QObject::tr( "Indexed layer" ) ) );
73}
74
75QVariantMap QgsSpatialIndexAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
76{
77 QgsVectorLayer *layer = parameterAsVectorLayer( parameters, QStringLiteral( "INPUT" ), context );
78
79 if ( !layer )
80 throw QgsProcessingException( QObject::tr( "Could not load source layer for %1." ).arg( QLatin1String( "INPUT" ) ) );
81
82 QgsVectorDataProvider *provider = layer->dataProvider();
83
85 {
86 if ( !provider->createSpatialIndex() )
87 {
88 feedback->pushInfo( QObject::tr( "Could not create spatial index" ) );
89 }
90 }
91 else
92 {
93 feedback->pushInfo( QObject::tr( "Layer's data provider does not support spatial indexes" ) );
94 }
95
96 QVariantMap outputs;
97 outputs.insert( QStringLiteral( "OUTPUT" ), layer->id() );
98 return outputs;
99}
100
QFlags< ProcessingAlgorithmFlag > ProcessingAlgorithmFlags
Flags indicating how and when an algorithm operates and should be exposed to users.
Definition qgis.h:3076
@ NoThreading
Algorithm is not thread safe and cannot be run in a background thread, e.g. for algorithms which mani...
QString id
Definition qgsmaplayer.h:78
virtual Qgis::ProcessingAlgorithmFlags flags() const
Returns the flags indicating how and when the algorithm operates and should be exposed to users.
Contains information about the context in which a processing algorithm is executed.
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.
A vector layer output for processing algorithms.
A vector layer (with or without geometry) parameter for processing algorithms.
This is the base class for vector data providers.
@ CreateSpatialIndex
Allows creation of spatial index.
virtual bool createSpatialIndex()
Creates a spatial index on the datasource (if supported by the provider type).
virtual Q_INVOKABLE QgsVectorDataProvider::Capabilities capabilities() const
Returns flags containing the supported capabilities.
Represents a vector layer which manages a vector based data sets.
QgsVectorDataProvider * dataProvider() FINAL
Returns the layer's data provider, it may be nullptr.