QGIS API Documentation 3.27.0-Master (a46f227e17)
qgsalgorithmsegmentize.cpp
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1/***************************************************************************
2 qgsalgorithmsegmentize.cpp
3 ---------------------
4 begin : March 2018
5 copyright : (C) 2018 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
21
22QString QgsSegmentizeByMaximumDistanceAlgorithm::name() const
23{
24 return QStringLiteral( "segmentizebymaxdistance" );
25}
26
27QString QgsSegmentizeByMaximumDistanceAlgorithm::displayName() const
28{
29 return QObject::tr( "Segmentize by maximum distance" );
30}
31
32QStringList QgsSegmentizeByMaximumDistanceAlgorithm::tags() const
33{
34 return QObject::tr( "straighten,linearize,densify,curves,curved,circular" ).split( ',' );
35}
36
37QString QgsSegmentizeByMaximumDistanceAlgorithm::group() const
38{
39 return QObject::tr( "Vector geometry" );
40}
41
42QString QgsSegmentizeByMaximumDistanceAlgorithm::groupId() const
43{
44 return QStringLiteral( "vectorgeometry" );
45}
46
47QString QgsSegmentizeByMaximumDistanceAlgorithm::outputName() const
48{
49 return QObject::tr( "Segmentized" );
50}
51
52QString QgsSegmentizeByMaximumDistanceAlgorithm::shortHelpString() const
53{
54 return QObject::tr( "This algorithm segmentizes a geometry by converting curved sections to linear sections.\n\n"
55 "The segmentization is performed by specifying the maximum allowed offset distance between the original"
56 "curve and the segmentized representation.\n\n"
57 "Non-curved geometries will be retained without change." );
58}
59
60QgsSegmentizeByMaximumDistanceAlgorithm *QgsSegmentizeByMaximumDistanceAlgorithm::createInstance() const
61{
62 return new QgsSegmentizeByMaximumDistanceAlgorithm();
63}
64
65QList<int> QgsSegmentizeByMaximumDistanceAlgorithm::inputLayerTypes() const
66{
68}
69
70void QgsSegmentizeByMaximumDistanceAlgorithm::initParameters( const QVariantMap & )
71{
72 std::unique_ptr< QgsProcessingParameterDistance > tolerance = std::make_unique< QgsProcessingParameterDistance >( QStringLiteral( "DISTANCE" ),
73 QObject::tr( "Maximum offset distance" ),
74 1.0, QStringLiteral( "INPUT" ), false, 0, 10000000.0 );
75 tolerance->setIsDynamic( true );
76 tolerance->setDynamicPropertyDefinition( QgsPropertyDefinition( QStringLiteral( "DISTANCE" ), QObject::tr( "Maximum offset distance" ), QgsPropertyDefinition::DoublePositive ) );
77 tolerance->setDynamicLayerParameterName( QStringLiteral( "INPUT" ) );
78 addParameter( tolerance.release() );
79}
80
81bool QgsSegmentizeByMaximumDistanceAlgorithm::supportInPlaceEdit( const QgsMapLayer *layer ) const
82{
83 Q_UNUSED( layer )
84 return false;
85}
86
87bool QgsSegmentizeByMaximumDistanceAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
88{
89 mTolerance = parameterAsDouble( parameters, QStringLiteral( "DISTANCE" ), context );
90 mDynamicTolerance = QgsProcessingParameters::isDynamic( parameters, QStringLiteral( "DISTANCE" ) );
91 if ( mDynamicTolerance )
92 mToleranceProperty = parameters.value( QStringLiteral( "DISTANCE" ) ).value< QgsProperty >();
93
94 return true;
95}
96
97QgsFeatureList QgsSegmentizeByMaximumDistanceAlgorithm::processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback * )
98{
99 QgsFeature f = feature;
100 if ( f.hasGeometry() )
101 {
102 QgsGeometry geometry = f.geometry();
103 double tolerance = mTolerance;
104 if ( mDynamicTolerance )
105 tolerance = mToleranceProperty.valueAsDouble( context.expressionContext(), tolerance );
107 f.setGeometry( geometry );
108 }
109 return QgsFeatureList() << f;
110}
111
112
113
114
115
116QString QgsSegmentizeByMaximumAngleAlgorithm::name() const
117{
118 return QStringLiteral( "segmentizebymaxangle" );
119}
120
121QString QgsSegmentizeByMaximumAngleAlgorithm::displayName() const
122{
123 return QObject::tr( "Segmentize by maximum angle" );
124}
125
126QStringList QgsSegmentizeByMaximumAngleAlgorithm::tags() const
127{
128 return QObject::tr( "straighten,linearize,densify,curves,curved,circular,angle" ).split( ',' );
129}
130
131QString QgsSegmentizeByMaximumAngleAlgorithm::group() const
132{
133 return QObject::tr( "Vector geometry" );
134}
135
136QString QgsSegmentizeByMaximumAngleAlgorithm::groupId() const
137{
138 return QStringLiteral( "vectorgeometry" );
139}
140
141QString QgsSegmentizeByMaximumAngleAlgorithm::outputName() const
142{
143 return QObject::tr( "Segmentized" );
144}
145
146QString QgsSegmentizeByMaximumAngleAlgorithm::shortHelpString() const
147{
148 return QObject::tr( "This algorithm segmentizes a geometry by converting curved sections to linear sections.\n\n"
149 "The segmentization is performed by specifying the maximum allowed radius angle between vertices "
150 "on the straightened geometry (e.g the angle of the arc created from the original arc center to consecutive "
151 "output vertices on the linearized geometry).\n\n"
152 "Non-curved geometries will be retained without change." );
153}
154
155QgsSegmentizeByMaximumAngleAlgorithm *QgsSegmentizeByMaximumAngleAlgorithm::createInstance() const
156{
157 return new QgsSegmentizeByMaximumAngleAlgorithm();
158}
159
160QList<int> QgsSegmentizeByMaximumAngleAlgorithm::inputLayerTypes() const
161{
163}
164
165void QgsSegmentizeByMaximumAngleAlgorithm::initParameters( const QVariantMap & )
166{
167 std::unique_ptr< QgsProcessingParameterNumber > tolerance = std::make_unique< QgsProcessingParameterNumber >( QStringLiteral( "ANGLE" ),
168 QObject::tr( "Maximum angle between vertices (degrees)" ), QgsProcessingParameterNumber::Double,
169 5.0, false, 0, 360.0 );
170 tolerance->setIsDynamic( true );
171 tolerance->setDynamicPropertyDefinition( QgsPropertyDefinition( QStringLiteral( "ANGLE" ), QObject::tr( "Maximum angle between vertices (degrees)" ), QgsPropertyDefinition::DoublePositive ) );
172 tolerance->setDynamicLayerParameterName( QStringLiteral( "INPUT" ) );
173 addParameter( tolerance.release() );
174}
175
176bool QgsSegmentizeByMaximumAngleAlgorithm::supportInPlaceEdit( const QgsMapLayer *layer ) const
177{
178 Q_UNUSED( layer )
179 return false;
180}
181
182bool QgsSegmentizeByMaximumAngleAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
183{
184 mTolerance = parameterAsDouble( parameters, QStringLiteral( "ANGLE" ), context );
185 mDynamicTolerance = QgsProcessingParameters::isDynamic( parameters, QStringLiteral( "ANGLE" ) );
186 if ( mDynamicTolerance )
187 mToleranceProperty = parameters.value( QStringLiteral( "ANGLE" ) ).value< QgsProperty >();
188
189 return true;
190}
191
192QgsFeatureList QgsSegmentizeByMaximumAngleAlgorithm::processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback * )
193{
194 QgsFeature f = feature;
195 if ( f.hasGeometry() )
196 {
197 QgsGeometry geometry = f.geometry();
198 double tolerance = mTolerance;
199 if ( mDynamicTolerance )
200 tolerance = mToleranceProperty.valueAsDouble( context.expressionContext(), tolerance );
201 geometry.convertToStraightSegment( M_PI * tolerance / 180.0, QgsAbstractGeometry::MaximumAngle );
202 f.setGeometry( geometry );
203 }
204 return QgsFeatureList() << f;
205}
206
208
209
@ MaximumDifference
Maximum distance between an arbitrary point on the original curve and closest point on its approximat...
@ MaximumAngle
Maximum angle between generating radii (lines from arc center to output vertices)
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
QgsGeometry geometry
Definition: qgsfeature.h:67
bool hasGeometry() const
Returns true if the feature has an associated geometry.
Definition: qgsfeature.cpp:230
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
Definition: qgsfeature.cpp:170
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:164
void convertToStraightSegment(double tolerance=M_PI/180., QgsAbstractGeometry::SegmentationToleranceType toleranceType=QgsAbstractGeometry::MaximumAngle)
Converts the geometry to straight line segments, if it is a curved geometry type.
Base class for all map layer types.
Definition: qgsmaplayer.h:73
Contains information about the context in which a processing algorithm is executed.
QgsExpressionContext & expressionContext()
Returns the expression context.
Base class for providing feedback from a processing algorithm.
static bool isDynamic(const QVariantMap &parameters, const QString &name)
Returns true if the parameter with matching name is a dynamic parameter, and must be evaluated once f...
@ TypeVectorLine
Vector line layers.
Definition: qgsprocessing.h:50
@ TypeVectorPolygon
Vector polygon layers.
Definition: qgsprocessing.h:51
Definition for a property.
Definition: qgsproperty.h:47
@ DoublePositive
Positive double value (including 0)
Definition: qgsproperty.h:58
A store for object properties.
Definition: qgsproperty.h:231
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:922