QGIS API Documentation 3.39.0-Master (67e056379ed)
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qgsalgorithmrotate.cpp
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1/***************************************************************************
2 qgsalgorithmrotate.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
18#include "qgsalgorithmrotate.h"
19
21
22QString QgsRotateFeaturesAlgorithm::name() const
23{
24 return QStringLiteral( "rotatefeatures" );
25}
26
27QString QgsRotateFeaturesAlgorithm::displayName() const
28{
29 return QObject::tr( "Rotate" );
30}
31
32QStringList QgsRotateFeaturesAlgorithm::tags() const
33{
34 return QObject::tr( "rotate,around,center,point" ).split( ',' );
35}
36
37QString QgsRotateFeaturesAlgorithm::group() const
38{
39 return QObject::tr( "Vector geometry" );
40}
41
42QString QgsRotateFeaturesAlgorithm::groupId() const
43{
44 return QStringLiteral( "vectorgeometry" );
45}
46
47QString QgsRotateFeaturesAlgorithm::outputName() const
48{
49 return QObject::tr( "Rotated" );
50}
51
52QString QgsRotateFeaturesAlgorithm::shortHelpString() const
53{
54 return QObject::tr( "This algorithm rotates feature geometries, by the specified angle clockwise" )
55 + QStringLiteral( "\n\n" )
56 + QObject::tr( "Optionally, the rotation can occur around a preset point. If not set the rotation occurs around each feature's centroid." );
57}
58
59QgsRotateFeaturesAlgorithm *QgsRotateFeaturesAlgorithm::createInstance() const
60{
61 return new QgsRotateFeaturesAlgorithm();
62}
63
64void QgsRotateFeaturesAlgorithm::initParameters( const QVariantMap & )
65{
66 std::unique_ptr< QgsProcessingParameterNumber > rotation = std::make_unique< QgsProcessingParameterNumber >( QStringLiteral( "ANGLE" ),
67 QObject::tr( "Rotation (degrees clockwise)" ), Qgis::ProcessingNumberParameterType::Double,
68 0.0 );
69 rotation->setIsDynamic( true );
70 rotation->setDynamicPropertyDefinition( QgsPropertyDefinition( QStringLiteral( "ANGLE" ), QObject::tr( "Rotation (degrees clockwise)" ), QgsPropertyDefinition::Rotation ) );
71 rotation->setDynamicLayerParameterName( QStringLiteral( "INPUT" ) );
72 addParameter( rotation.release() );
73
74 std::unique_ptr< QgsProcessingParameterPoint > anchor = std::make_unique< QgsProcessingParameterPoint >( QStringLiteral( "ANCHOR" ),
75 QObject::tr( "Rotation anchor point" ), QVariant(), true );
76 addParameter( anchor.release() );
77}
78
79bool QgsRotateFeaturesAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
80{
81 mAngle = parameterAsDouble( parameters, QStringLiteral( "ANGLE" ), context );
82 mDynamicAngle = QgsProcessingParameters::isDynamic( parameters, QStringLiteral( "ANGLE" ) );
83 if ( mDynamicAngle )
84 mAngleProperty = parameters.value( QStringLiteral( "ANGLE" ) ).value< QgsProperty >();
85
86 mUseAnchor = parameters.value( QStringLiteral( "ANCHOR" ) ).isValid();
87 if ( mUseAnchor )
88 {
89 mAnchor = parameterAsPoint( parameters, QStringLiteral( "ANCHOR" ), context );
90 mAnchorCrs = parameterAsPointCrs( parameters, QStringLiteral( "ANCHOR" ), context );
91 }
92
93 return true;
94}
95
96QgsFeatureList QgsRotateFeaturesAlgorithm::processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
97{
98 if ( mUseAnchor && !mTransformedAnchor )
99 {
100 mTransformedAnchor = true;
101 if ( mAnchorCrs != sourceCrs() )
102 {
103 const QgsCoordinateTransform ct( mAnchorCrs, sourceCrs(), context.transformContext() );
104 try
105 {
106 mAnchor = ct.transform( mAnchor );
107 }
108 catch ( QgsCsException & )
109 {
110 throw QgsProcessingException( QObject::tr( "Could not transform anchor point to destination CRS" ) );
111 }
112 }
113 }
114
115 QgsFeature f = feature;
116 if ( f.hasGeometry() )
117 {
118 QgsGeometry geometry = f.geometry();
119
120 double angle = mAngle;
121 if ( mDynamicAngle )
122 angle = mAngleProperty.valueAsDouble( context.expressionContext(), angle );
123
124 if ( mUseAnchor )
125 {
126 geometry.rotate( angle, mAnchor );
127 f.setGeometry( geometry );
128 }
129 else
130 {
131 const QgsGeometry centroid = geometry.centroid();
132 if ( !centroid.isNull() )
133 {
134 geometry.rotate( angle, centroid.asPoint() );
135 f.setGeometry( geometry );
136 }
137 else
138 {
139 feedback->reportError( QObject::tr( "Could not calculate centroid for feature %1: %2" ).arg( feature.id() ).arg( centroid.lastError() ) );
140 }
141 }
142 }
143 return QgsFeatureList() << f;
144}
145
146
148
149
Class for doing transforms between two map coordinate systems.
Custom exception class for Coordinate Reference System related exceptions.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition qgsfeature.h:58
QgsFeatureId id
Definition qgsfeature.h:66
QgsGeometry geometry
Definition qgsfeature.h:69
bool hasGeometry() const
Returns true if the feature has an associated geometry.
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
A geometry is the spatial representation of a feature.
QgsGeometry centroid() const
Returns the center of mass of a geometry.
Qgis::GeometryOperationResult rotate(double rotation, const QgsPointXY &center)
Rotate this geometry around the Z axis.
Contains information about the context in which a processing algorithm is executed.
QgsExpressionContext & expressionContext()
Returns the expression context.
QgsCoordinateTransformContext transformContext() const
Returns the coordinate transform context.
Custom exception class for processing related exceptions.
Base class for providing feedback from a processing algorithm.
virtual void reportError(const QString &error, bool fatalError=false)
Reports that the algorithm encountered an error while executing.
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...
Definition for a property.
Definition qgsproperty.h:45
@ Rotation
Rotation (value between 0-360 degrees)
Definition qgsproperty.h:58
A store for object properties.
QVariant value(const QgsExpressionContext &context, const QVariant &defaultValue=QVariant(), bool *ok=nullptr) const
Calculates the current value of the property, including any transforms which are set for the property...
double ANALYSIS_EXPORT angle(QgsPoint *p1, QgsPoint *p2, QgsPoint *p3, QgsPoint *p4)
Calculates the angle between two segments (in 2 dimension, z-values are ignored)
QList< QgsFeature > QgsFeatureList