QGIS API Documentation  3.27.0-Master (0e23467727)
qgsmergedfeaturerenderer.h
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1 /***************************************************************************
2  qgsmergedfeaturerenderer.h
3  ---------------------
4  begin : December 2020
5  copyright : (C) 2020 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 #ifndef QGSMERGEDFEATURERENDERER_H
16 #define QGSMERGEDFEATURERENDERER_H
17 
18 #include "qgis_core.h"
19 #include "qgis_sip.h"
20 #include "qgis.h"
21 #include "qgsrenderer.h"
22 #include "qgsexpression.h"
23 #include "qgsfeature.h"
24 #include "qgsgeometry.h"
25 #include "qgsrendercontext.h"
26 
40 class CORE_EXPORT QgsMergedFeatureRenderer : public QgsFeatureRenderer
41 {
42  public:
43 
49 
54 
56  static QgsFeatureRenderer *create( QDomElement &element, const QgsReadWriteContext &context ) SIP_FACTORY;
57 
58  QgsMergedFeatureRenderer *clone() const override SIP_FACTORY;
59  void startRender( QgsRenderContext &context, const QgsFields &fields ) override;
60 
71  bool renderFeature( const QgsFeature &feature, QgsRenderContext &context, int layer = -1, bool selected = false, bool drawVertexMarker = false ) override SIP_THROW( QgsCsException );
72 
77  void stopRender( QgsRenderContext &context ) override;
78 
79  QString dump() const override;
80  QSet<QString> usedAttributes( const QgsRenderContext &context ) const override;
81  bool filterNeedsGeometry() const override;
82  QgsFeatureRenderer::Capabilities capabilities() override;
83  QgsSymbolList symbols( QgsRenderContext &context ) const override;
84  QgsSymbol *symbolForFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
85  QgsSymbol *originalSymbolForFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
86  QgsSymbolList symbolsForFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
87  QgsSymbolList originalSymbolsForFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
88  QSet< QString > legendKeysForFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
89  QString legendKeyToExpression( const QString &key, QgsVectorLayer *layer, bool &ok ) const override;
90  QgsLegendSymbolList legendSymbolItems() const override;
91  bool willRenderFeature( const QgsFeature &feature, QgsRenderContext &context ) const override;
92  QDomElement save( QDomDocument &doc, const QgsReadWriteContext &context ) override;
93  void setEmbeddedRenderer( QgsFeatureRenderer *subRenderer SIP_TRANSFER ) override;
94  const QgsFeatureRenderer *embeddedRenderer() const override;
95  void setLegendSymbolItem( const QString &key, QgsSymbol *symbol ) override;
96  bool legendSymbolItemsCheckable() const override;
97  bool legendSymbolItemChecked( const QString &key ) override;
98  void checkLegendSymbolItem( const QString &key, bool state = true ) override;
99  bool accept( QgsStyleEntityVisitorInterface *visitor ) const override;
100 
105  static QgsMergedFeatureRenderer *convertFromRenderer( const QgsFeatureRenderer *renderer ) SIP_FACTORY;
106 
107  protected:
108 
114  QgsMergedFeatureRenderer( const QString &type, QgsFeatureRenderer *embeddedRenderer SIP_TRANSFER );
115 
120  {
124  };
125 
127  GeometryOperation mOperation = Merge;
128 
130  std::unique_ptr<QgsFeatureRenderer> mSubRenderer;
131 
132  private:
133 
135  struct CombinedFeature
136  {
137  QVector<QgsGeometry> geometries; //< list of geometries
138  QgsFeature feature; //< one feature (for attriute-based rendering)
139  };
140  typedef QVector<CombinedFeature> FeatureCategoryVector;
142  FeatureCategoryVector mFeaturesCategories;
143 
145  QMap<QByteArray, int> mSymbolCategories;
146 
148  QgsPolygonXY mExtentPolygon;
149 
151  QgsRenderContext mContext;
152 
154  QgsFields mFields;
155 
160  struct FeatureDecoration
161  {
162  QgsFeature feature;
163  bool selected;
164  bool drawMarkers;
165  int layer;
166  FeatureDecoration( const QgsFeature &a_feature, bool a_selected, bool a_drawMarkers, int a_layer )
167  : feature( a_feature )
168  , selected( a_selected )
169  , drawMarkers( a_drawMarkers )
170  , layer( a_layer )
171  {}
172  };
173  QList<FeatureDecoration> mFeatureDecorations;
174 
175 };
176 
177 
178 #endif // QGSMERGEDFEATURERENDERER_H
Custom exception class for Coordinate Reference System related exceptions.
Definition: qgsexception.h:66
virtual QgsFeatureRenderer * clone() const =0
Create a deep copy of this renderer.
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
QgsMergedFeatureRenderer is a polygon or line-only feature renderer used to renderer a set of feature...
GeometryOperation
Operations to apply to collected geometries prior to rendering.
@ Merge
Merge features (union/dissolve)
@ InvertOnly
Invert features only (polygons only)
@ MergeAndInvert
Merge and invert features (polygons only)
QgsMergedFeatureRenderer(const QgsMergedFeatureRenderer &)=delete
Direct copies are forbidden. Use clone() instead.
std::unique_ptr< QgsFeatureRenderer > mSubRenderer
Embedded renderer.
QgsMergedFeatureRenderer & operator=(const QgsMergedFeatureRenderer &)=delete
Direct copies are forbidden. Use clone() instead.
The class is used as a container of context for various read/write operations on other objects.
Contains information about the context of a rendering operation.
An interface for classes which can visit style entity (e.g.
Abstract base class for all rendered symbols.
Definition: qgssymbol.h:93
Represents a vector layer which manages a vector based data sets.
#define SIP_THROW(name)
Definition: qgis_sip.h:198
#define SIP_TRANSFER
Definition: qgis_sip.h:36
#define SIP_FACTORY
Definition: qgis_sip.h:76
QVector< QgsPolylineXY > QgsPolygonXY
Polygon: first item of the list is outer ring, inner rings (if any) start from second item.
Definition: qgsgeometry.h:76
QList< QgsLegendSymbolItem > QgsLegendSymbolList
QList< QgsSymbol * > QgsSymbolList
Definition: qgsrenderer.h:44