QGIS API Documentation  3.14.0-Pi (9f7028fd23)
qgsalgorithmextractlayoutmapextent.cpp
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1 /***************************************************************************
2  qgsalgorithmextractlayoutmapextent.cpp
3  ---------------------
4  begin : March 2019
5  copyright : (C) 2019 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 
21 #include "layout/qgslayout.h"
22 #include "layout/qgsprintlayout.h"
23 #include "qgsprocessingoutputs.h"
24 
26 
27 QString QgsLayoutMapExtentToLayerAlgorithm::name() const
28 {
29  return QStringLiteral( "printlayoutmapextenttolayer" );
30 }
31 
32 QString QgsLayoutMapExtentToLayerAlgorithm::displayName() const
33 {
34  return QObject::tr( "Print layout map extent to layer" );
35 }
36 
37 QStringList QgsLayoutMapExtentToLayerAlgorithm::tags() const
38 {
39  return QObject::tr( "layout,composer,composition,visible" ).split( ',' );
40 }
41 
42 QString QgsLayoutMapExtentToLayerAlgorithm::group() const
43 {
44  return QObject::tr( "Cartography" );
45 }
46 
47 QString QgsLayoutMapExtentToLayerAlgorithm::groupId() const
48 {
49  return QStringLiteral( "cartography" );
50 }
51 
52 QString QgsLayoutMapExtentToLayerAlgorithm::shortDescription() const
53 {
54  return QObject::tr( "Creates a polygon layer containing the extent of a print layout map item." );
55 }
56 
57 void QgsLayoutMapExtentToLayerAlgorithm::initAlgorithm( const QVariantMap & )
58 {
59  addParameter( new QgsProcessingParameterLayout( QStringLiteral( "LAYOUT" ), QObject::tr( "Print layout" ) ) );
60  addParameter( new QgsProcessingParameterLayoutItem( QStringLiteral( "MAP" ), QObject::tr( "Map item" ), QVariant(), QStringLiteral( "LAYOUT" ), QgsLayoutItemRegistry::LayoutMap, true ) );
61  auto crsParam = qgis::make_unique< QgsProcessingParameterCrs >( QStringLiteral( "CRS" ), QObject::tr( "Override CRS" ), QVariant(), true );
62  crsParam->setFlags( crsParam->flags() | QgsProcessingParameterDefinition::FlagAdvanced );
63  addParameter( crsParam.release() );
64  addParameter( new QgsProcessingParameterFeatureSink( QStringLiteral( "OUTPUT" ), QObject::tr( "Extent" ), QgsProcessing::TypeVectorPolygon ) );
65  addOutput( new QgsProcessingOutputNumber( QStringLiteral( "WIDTH" ), QObject::tr( "Map width" ) ) );
66  addOutput( new QgsProcessingOutputNumber( QStringLiteral( "HEIGHT" ), QObject::tr( "Map height" ) ) );
67  addOutput( new QgsProcessingOutputNumber( QStringLiteral( "SCALE" ), QObject::tr( "Map scale" ) ) );
68  addOutput( new QgsProcessingOutputNumber( QStringLiteral( "ROTATION" ), QObject::tr( "Map rotation" ) ) );
69 }
70 
71 QString QgsLayoutMapExtentToLayerAlgorithm::shortHelpString() const
72 {
73  return QObject::tr( "This algorithm creates a polygon layer containing the extent of a print layout map item (or items), "
74  "with attributes specifying the map size (in layout units), scale and rotation.\n\n"
75  "If the map item parameter is specified, then only the matching map extent will be exported. If it "
76  "is not specified, all map extents from the layout will be exported.\n\n"
77  "Optionally, a specific output CRS can be specified. If it is not specified, the original map "
78  "item CRS will be used." );
79 }
80 
81 QgsLayoutMapExtentToLayerAlgorithm *QgsLayoutMapExtentToLayerAlgorithm::createInstance() const
82 {
83  return new QgsLayoutMapExtentToLayerAlgorithm();
84 }
85 
86 bool QgsLayoutMapExtentToLayerAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
87 {
88  // this needs to be done in main thread, layouts are not thread safe
89  QgsPrintLayout *layout = parameterAsLayout( parameters, QStringLiteral( "LAYOUT" ), context );
90  if ( !layout )
91  throw QgsProcessingException( QObject::tr( "Cannot find layout with name \"%1\"" ).arg( parameters.value( QStringLiteral( "LAYOUT" ) ).toString() ) );
92 
93  QgsLayoutItemMap *map = qobject_cast< QgsLayoutItemMap * >( parameterAsLayoutItem( parameters, QStringLiteral( "MAP" ), context, layout ) );
94  if ( !map && parameters.value( QStringLiteral( "MAP" ) ).isValid() )
95  throw QgsProcessingException( QObject::tr( "Cannot find matching map item with ID %1" ).arg( parameters.value( QStringLiteral( "MAP" ) ).toString() ) );
96 
97  QList< QgsLayoutItemMap *> maps;
98  if ( map )
99  maps << map;
100  else
101  layout->layoutItems( maps );
102 
103  QgsCoordinateReferenceSystem overrideCrs = parameterAsCrs( parameters, QStringLiteral( "CRS" ), context );
104 
105  mFeatures.reserve( maps.size() );
106  for ( QgsLayoutItemMap *map : maps )
107  {
108  if ( !mCrs.isValid() )
109  mCrs = !overrideCrs.isValid() ? map->crs() : overrideCrs;
110 
111  QgsGeometry extent = QgsGeometry::fromQPolygonF( map->visibleExtentPolygon() );
112  if ( map->crs() != mCrs )
113  {
114  try
115  {
116  extent.transform( QgsCoordinateTransform( map->crs(), mCrs, context.transformContext() ) );
117  }
118  catch ( QgsCsException & )
119  {
120  feedback->reportError( QObject::tr( "Error reprojecting map to destination CRS" ) );
121  continue;
122  }
123  }
124 
125  mWidth = map->rect().width();
126  mHeight = map->rect().height();
127  mScale = map->scale();
128  mRotation = map->mapRotation();
129 
130  QgsFeature f;
131  f.setAttributes( QgsAttributes() << map->displayName() << mWidth << mHeight << mScale << mRotation );
132  f.setGeometry( extent );
133 
134  mFeatures << f;
135  }
136  return true;
137 }
138 
139 QVariantMap QgsLayoutMapExtentToLayerAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
140 {
141  QgsFields fields;
142  fields.append( QgsField( QStringLiteral( "map" ), QVariant::String ) );
143  fields.append( QgsField( QStringLiteral( "width" ), QVariant::Double ) );
144  fields.append( QgsField( QStringLiteral( "height" ), QVariant::Double ) );
145  fields.append( QgsField( QStringLiteral( "scale" ), QVariant::Double ) );
146  fields.append( QgsField( QStringLiteral( "rotation" ), QVariant::Double ) );
147 
148  QString dest;
149  std::unique_ptr< QgsFeatureSink > sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, dest, fields, QgsWkbTypes::Polygon, mCrs ) );
150  if ( !sink )
151  throw QgsProcessingException( invalidSinkError( parameters, QStringLiteral( "OUTPUT" ) ) );
152 
153  for ( QgsFeature &f : mFeatures )
154  sink->addFeature( f, QgsFeatureSink::FastInsert );
155 
156  feedback->setProgress( 100 );
157 
158  QVariantMap outputs;
159  outputs.insert( QStringLiteral( "OUTPUT" ), dest );
160  // these numeric outputs only have value for single-map layouts
161  outputs.insert( QStringLiteral( "WIDTH" ), mFeatures.size() == 1 ? mWidth : QVariant() );
162  outputs.insert( QStringLiteral( "HEIGHT" ), mFeatures.size() == 1 ? mHeight : QVariant() );
163  outputs.insert( QStringLiteral( "SCALE" ), mFeatures.size() == 1 ? mScale : QVariant() );
164  outputs.insert( QStringLiteral( "ROTATION" ), mFeatures.size() == 1 ? mRotation : QVariant() );
165  return outputs;
166 }
167 
169 
QgsFeedback::setProgress
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition: qgsfeedback.h:75
QgsGeometry::transform
OperationResult transform(const QgsCoordinateTransform &ct, QgsCoordinateTransform::TransformDirection direction=QgsCoordinateTransform::ForwardTransform, bool transformZ=false) SIP_THROW(QgsCsException)
Transforms this geometry as described by the coordinate transform ct.
Definition: qgsgeometry.cpp:2836
QgsLayout::layoutItems
void layoutItems(QList< T * > &itemList) const
Returns a list of layout items of a specific type.
Definition: qgslayout.h:121
QgsProcessingFeedback
Definition: qgsprocessingfeedback.h:37
QgsProcessingFeedback::reportError
virtual void reportError(const QString &error, bool fatalError=false)
Reports that the algorithm encountered an error while executing.
Definition: qgsprocessingfeedback.cpp:39
QgsProcessing::TypeVectorPolygon
@ TypeVectorPolygon
Vector polygon layers.
Definition: qgsprocessing.h:50
QgsFields
Definition: qgsfields.h:44
QgsProcessingParameterDefinition::FlagAdvanced
@ FlagAdvanced
Parameter is an advanced parameter which should be hidden from users by default.
Definition: qgsprocessingparameters.h:419
QgsFields::append
bool append(const QgsField &field, FieldOrigin origin=OriginProvider, int originIndex=-1)
Appends a field. The field must have unique name, otherwise it is rejected (returns false)
Definition: qgsfields.cpp:59
QgsProcessingOutputNumber
Definition: qgsprocessingoutputs.h:294
QgsProcessingParameterFeatureSink
Definition: qgsprocessingparameters.h:2773
QgsCsException
Definition: qgsexception.h:65
QgsPrintLayout
Print layout, a QgsLayout subclass for static or atlas-based layouts.
Definition: qgsprintlayout.h:30
QgsFeature::setGeometry
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
Definition: qgsfeature.cpp:137
QgsProcessingContext
Definition: qgsprocessingcontext.h:43
QgsProcessingParameterLayoutItem
Definition: qgsprocessingparameters.h:3216
QgsCoordinateReferenceSystem::isValid
bool isValid() const
Returns whether this CRS is correctly initialized and usable.
Definition: qgscoordinatereferencesystem.cpp:902
QgsProcessingContext::transformContext
QgsCoordinateTransformContext transformContext() const
Returns the coordinate transform context.
Definition: qgsprocessingcontext.h:135
qgslayout.h
QgsCoordinateReferenceSystem
Definition: qgscoordinatereferencesystem.h:206
QgsProcessingParameterLayout
Definition: qgsprocessingparameters.h:3178
qgsalgorithmextractlayoutmapextent.h
QgsLayoutItemMap
Layout graphical items for displaying a map.
Definition: qgslayoutitemmap.h:39
qgsprocessingoutputs.h
QgsGeometry
Definition: qgsgeometry.h:122
QgsWkbTypes::Polygon
@ Polygon
Definition: qgswkbtypes.h:73
qgsprintlayout.h
QgsLayoutItemRegistry::LayoutMap
@ LayoutMap
Map item.
Definition: qgslayoutitemregistry.h:317
QgsAttributes
Definition: qgsattributes.h:57
QgsGeometry::fromQPolygonF
static QgsGeometry fromQPolygonF(const QPolygonF &polygon)
Construct geometry from a QPolygonF.
Definition: qgsgeometry.cpp:3095
QgsFeature
Definition: qgsfeature.h:55
QgsFeature::setAttributes
void setAttributes(const QgsAttributes &attrs)
Sets the feature's attributes.
Definition: qgsfeature.cpp:127
QgsCoordinateTransform
Definition: qgscoordinatetransform.h:52
qgslayoutitemregistry.h
QgsProcessingException
Definition: qgsexception.h:82
QgsFeatureSink::FastInsert
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
Definition: qgsfeaturesink.h:70
qgslayoutitemmap.h
QgsField
Definition: qgsfield.h:49