QGIS API Documentation  2.99.0-Master (37c43df)
qgsdiagram.h
Go to the documentation of this file.
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 <QPen>
19 #include <QBrush>
20 #include "qgsexpression.h" //for QMap with QgsExpression
21 
22 class QPainter;
23 class QPointF;
24 class QgsDiagramSettings;
26 class QgsFeature;
27 class QgsRenderContext;
29 class QgsFields;
30 class QgsAttributes;
31 
32 
35 class CORE_EXPORT QgsDiagram
36 {
37  public:
38  virtual ~QgsDiagram() { clearCache(); }
39 
42  virtual QgsDiagram* clone() const = 0;
43 
44  void clearCache();
45 
51  QgsExpression* getExpression( const QString& expression, const QgsExpressionContext& context );
52 
54  virtual void renderDiagram( const QgsFeature& feature, QgsRenderContext& c, const QgsDiagramSettings& s, QPointF position ) = 0;
55 
59  virtual QString diagramName() const = 0;
61  virtual QSizeF diagramSize( const QgsAttributes& attributes, const QgsRenderContext& c, const QgsDiagramSettings& s ) = 0;
63  virtual QSizeF diagramSize( const QgsFeature& feature, const QgsRenderContext& c, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) = 0;
64 
71  virtual double legendSize( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const = 0;
72 
73  protected:
74  QgsDiagram();
75  QgsDiagram( const QgsDiagram& other );
76 
82  void setPenWidth( QPen& pen, const QgsDiagramSettings& s, const QgsRenderContext& c );
83 
91  QSizeF sizePainterUnits( QSizeF size, const QgsDiagramSettings& s, const QgsRenderContext& c );
92 
100  float sizePainterUnits( float l, const QgsDiagramSettings& s, const QgsRenderContext& c );
101 
108  QFont scaledFont( const QgsDiagramSettings& s, const QgsRenderContext& c );
109 
116  QSizeF sizeForValue( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const;
117 
118  private:
119  QMap<QString, QgsExpression*> mExpressions;
120 };
121 
122 #endif // QGSDIAGRAM_H
Class for parsing and evaluation of expressions (formerly called "search strings").
virtual ~QgsDiagram()
Definition: qgsdiagram.h:38
Container of fields for a vector layer.
Definition: qgsfields.h:36
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:135
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
Base class for all diagram types.
Definition: qgsdiagram.h:35
Additional diagram settings for interpolated size rendering.
Contains information about the context of a rendering operation.
A vector of attributes.
Definition: qgsfeature.h:55
Stores the settings for rendering a single diagram.