QGIS API Documentation  2.99.0-Master (b698612)
qgsdiagram.h
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1 /***************************************************************************
2  qgsdiagram.h
3  ---------------------
4  begin : March 2011
5  copyright : (C) 2011 by Marco Hugentobler
6  email : marco dot hugentobler at sourcepole dot ch
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 QGSDIAGRAM_H
16 #define QGSDIAGRAM_H
17 
18 #include "qgis_core.h"
19 #include "qgis.h"
20 #include <QPen>
21 #include <QBrush>
22 #include "qgsexpression.h" //for QMap with QgsExpression
23 
24 class QPainter;
25 class QPointF;
26 class QgsDiagramSettings;
28 class QgsFeature;
29 class QgsRenderContext;
31 class QgsFields;
32 class QgsAttributes;
33 
34 
37 class CORE_EXPORT QgsDiagram
38 {
39  public:
40  virtual ~QgsDiagram() { clearCache(); }
41 
44  virtual QgsDiagram *clone() const = 0 SIP_FACTORY;
45 
46  void clearCache();
47 
53  QgsExpression *getExpression( const QString &expression, const QgsExpressionContext &context );
54 
56  virtual void renderDiagram( const QgsFeature &feature, QgsRenderContext &c, const QgsDiagramSettings &s, QPointF position ) = 0;
57 
61  virtual QString diagramName() const = 0;
63  virtual QSizeF diagramSize( const QgsAttributes &attributes, const QgsRenderContext &c, const QgsDiagramSettings &s ) = 0;
65  virtual QSizeF diagramSize( const QgsFeature &feature, const QgsRenderContext &c, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &is ) = 0;
66 
73  virtual double legendSize( double value, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &is ) const = 0;
74 
75  protected:
76  QgsDiagram();
77  QgsDiagram( const QgsDiagram &other );
78 
84  void setPenWidth( QPen &pen, const QgsDiagramSettings &s, const QgsRenderContext &c );
85 
93  QSizeF sizePainterUnits( QSizeF size, const QgsDiagramSettings &s, const QgsRenderContext &c );
94 
102  double sizePainterUnits( double l, const QgsDiagramSettings &s, const QgsRenderContext &c );
103 
110  QFont scaledFont( const QgsDiagramSettings &s, const QgsRenderContext &c );
111 
118  QSizeF sizeForValue( double value, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &is ) const;
119 
120  private:
121  QMap<QString, QgsExpression *> mExpressions;
122 };
123 
124 #endif // QGSDIAGRAM_H
virtual ~QgsDiagram()
Definition: qgsdiagram.h:40
Container of fields for a vector layer.
Definition: qgsfields.h:41
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:61
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
#define SIP_FACTORY
Definition: qgis_sip.h:57
Base class for all diagram types.
Definition: qgsdiagram.h:37
Additional diagram settings for interpolated size rendering.
Contains information about the context of a rendering operation.
A vector of attributes.
Definition: qgsattributes.h:57
Stores the settings for rendering a single diagram.