QGIS API Documentation  3.4.15-Madeira (e83d02e274)
qgsgeometrysimplifier.h
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1 /***************************************************************************
2  qgsgeometrysimplifier.h
3  ---------------------
4  begin : December 2013
5  copyright : (C) 2013 by Alvaro Huarte
6  email : http://wiki.osgeo.org/wiki/Alvaro_Huarte
7 
8  ***************************************************************************
9  * *
10  * This program is free software; you can redistribute it and/or modify *
11  * it under the terms of the GNU General Public License as published by *
12  * the Free Software Foundation; either version 2 of the License, or *
13  * (at your option) any later version. *
14  * *
15  ***************************************************************************/
16 
17 #ifndef QGSGEOMETRYSIMPLIFIER_H
18 #define QGSGEOMETRYSIMPLIFIER_H
19 
20 #include <QVector>
21 #include <QPointF>
22 
23 class QgsGeometry;
24 class QgsRectangle;
25 
26 #include "qgis_core.h"
27 
33 {
34  public:
35  virtual ~QgsAbstractGeometrySimplifier() = default;
36 
38  virtual QgsGeometry simplify( const QgsGeometry &geometry ) const = 0;
39 
40  // MapToPixel simplification helper methods
41  public:
43  static bool isGeneralizableByDeviceBoundingBox( const QgsRectangle &envelope, float mapToPixelTol = 1.0f );
45  static bool isGeneralizableByDeviceBoundingBox( const QVector<QPointF> &points, float mapToPixelTol = 1.0f );
46 };
47 
48 /***************************************************************************/
49 
58 {
59  public:
60 
65  QgsTopologyPreservingSimplifier( double tolerance );
66 
67  QgsGeometry simplify( const QgsGeometry &geometry ) const override;
68 
69  protected:
71  double mTolerance;
72 
73 };
74 
75 #endif // QGSGEOMETRYSIMPLIFIER_H
Implementation of GeometrySimplifier using the Douglas-Peucker algorithm.
A rectangle specified with double values.
Definition: qgsrectangle.h:40
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:106
double mTolerance
Distance tolerance for the simplification.
virtual QgsGeometry simplify(const QgsGeometry &geometry) const =0
Returns a simplified version the specified geometry.
Abstract base class for simplify geometries using a specific algorithm.