QGIS API Documentation  2.99.0-Master (9fdd060)
qgsmaptopixelgeometrysimplifier.h
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1 /***************************************************************************
2  qgsmaptopixelgeometrysimplifier.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 *
12  * the Free Software Foundation; either version 2 of the License, or *
13  * (at your option) any later version. *
14  * *
15  ***************************************************************************/
16
17 #ifndef QGSMAPTOPIXELGEOMETRYSIMPLIFIER_H
18 #define QGSMAPTOPIXELGEOMETRYSIMPLIFIER_H
19
20 #include "qgis_core.h"
21 #include "qgis.h"
22 #include "qgsgeometrysimplifier.h"
23 #include <QPolygonF>
24
26 class QgsWkbPtr;
27 class QgsConstWkbPtr;
28
29
38 {
39  public:
42  {
43  Distance = 0,
44  SnapToGrid = 1,
45  Visvalingam = 2,
46  };
47
49  QgsMapToPixelSimplifier( int simplifyFlags, double tolerance, SimplifyAlgorithm simplifyAlgorithm = Distance );
50
53  {
54  NoFlags = 0,
55  SimplifyGeometry = 1,
56  SimplifyEnvelope = 2,
57  };
58
59  private:
61  static QgsGeometry simplifyGeometry( int simplifyFlags, SimplifyAlgorithm simplifyAlgorithm, QgsWkbTypes::Type wkbType, const QgsAbstractGeometry &geometry, const QgsRectangle &envelope, double map2pixelTol, bool isaLinearRing );
62
63  protected:
66
69
71  double mTolerance;
72
74  static float calculateLengthSquared2D( double x1, double y1, double x2, double y2 );
75
77  static bool equalSnapToGrid( double x1, double y1, double x2, double y2, double gridOriginX, double gridOriginY, float gridInverseSizeXY );
78
79  public:
81  int simplifyFlags() const { return mSimplifyFlags; }
83  void setSimplifyFlags( int simplifyFlags ) { mSimplifyFlags = simplifyFlags; }
84
86  SimplifyAlgorithm simplifyAlgorithm() const { return mSimplifyAlgorithm; }
88  void setSimplifyAlgorithm( SimplifyAlgorithm simplifyAlgorithm ) { mSimplifyAlgorithm = simplifyAlgorithm; }
89
91  virtual QgsGeometry simplify( const QgsGeometry &geometry ) const override;
92
94  void setTolerance( double value ) { mTolerance = value; }
95
96  // MapToPixel simplification helper methods
97  public:
98
100  static bool isGeneralizableByMapBoundingBox( const QgsRectangle &envelope, double map2pixelTol );
101
103  inline bool isGeneralizableByMapBoundingBox( const QgsRectangle &envelope ) const
104  {
105  return isGeneralizableByMapBoundingBox( envelope, mTolerance );
106  }
107 };
108
109 #endif // QGSMAPTOPIXELGEOMETRYSIMPLIFIER_H
A rectangle specified with double values.
Definition: qgsrectangle.h:39
void setSimplifyFlags(int simplifyFlags)
Sets the simplification hints of the vector layer managed.
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:94
SimplifyAlgorithm
Types of simplification algorithms that can be used.
Type
The WKB type describes the number of dimensions a geometry has.
Definition: qgswkbtypes.h:67
SimplifyAlgorithm simplifyAlgorithm() const
Gets the local simplification algorithm of the vector layer managed.
int simplifyFlags() const
Gets the simplification hints of the vector layer managed.
Abstract base class for all geometries.
void setTolerance(double value)
Sets the tolerance of the vector layer managed.
Implementation of GeometrySimplifier using the "MapToPixel" algorithm.
double mTolerance
Distance tolerance for the simplification.
void setSimplifyAlgorithm(SimplifyAlgorithm simplifyAlgorithm)
Sets the local simplification algorithm of the vector layer managed.
int mSimplifyFlags
Current simplification flags.
SimplifyAlgorithm mSimplifyAlgorithm
Current algorithm.
virtual QgsGeometry simplify(const QgsGeometry &geometry) const =0
Returns a simplified version the specified geometry.
SimplifyFlag
Applicable simplification flags.
bool isGeneralizableByMapBoundingBox(const QgsRectangle &envelope) const
Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel cont...
Abstract base class for simplify geometries using a specific algorithm.