QGIS API Documentation  3.21.0-Master (5b68dc587e)
qgssimplifymethod.cpp
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1 /***************************************************************************
2  qgssimplifymethod.cpp
3  ---------------------
4  begin : December 2013
5  copyright : (C) 2013 by Matthias Kuhn / Alvaro Huarte
6  email :
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 
16 #include "qgssimplifymethod.h"
17 #include "qgslogger.h"
18 #include "qgsgeometrysimplifier.h"
20 
21 
23 {
25 }
26 
27 void QgsSimplifyMethod::setTolerance( double tolerance )
28 {
30 }
31 
32 void QgsSimplifyMethod::setForceLocalOptimization( bool localOptimization )
33 {
34  mForceLocalOptimization = localOptimization;
35 }
36 
38 {
39  const QgsSimplifyMethod::MethodType methodType = simplifyMethod.methodType();
40 
41  // returns a geometry simplifier according to specified method
43  {
45  return new QgsMapToPixelSimplifier( simplifyFlags, simplifyMethod.tolerance(), QgsMapToPixelSimplifier::Distance );
46  }
48  {
49  return new QgsTopologyPreservingSimplifier( simplifyMethod.tolerance() );
50  }
51  else
52  {
53  QgsDebugMsg( QStringLiteral( "Simplification method type (%1) is not recognised" ).arg( methodType ) );
54  return nullptr;
55  }
56 }
Abstract base class for simplify geometries using a specific algorithm.
Implementation of GeometrySimplifier using the "MapToPixel" algorithm.
@ Distance
The simplification uses the distance between points to remove duplicate points.
@ SimplifyEnvelope
The geometries can be fully simplified by its BoundingBox.
@ SimplifyGeometry
The geometries can be simplified using the current map2pixel context state.
This class contains information about how to simplify geometries fetched from a QgsFeatureIterator.
void setTolerance(double tolerance)
Sets the tolerance of simplification in map units. Represents the maximum distance in map units betwe...
double tolerance() const
Gets the tolerance of simplification in map units. Represents the maximum distance in map units betwe...
void setForceLocalOptimization(bool localOptimization)
Sets whether the simplification executes after fetch the geometries from provider,...
double mTolerance
Simplification tolerance, it represents the maximum distance between two coordinates which can be con...
bool mForceLocalOptimization
Simplification executes after fetch the geometries from provider, otherwise it executes,...
MethodType mMethodType
Simplification method.
void setMethodType(MethodType methodType)
Sets the simplification type.
MethodType methodType() const
Gets the simplification type.
@ OptimizeForRendering
Simplify using the map2pixel data to optimize the rendering of geometries.
@ PreserveTopology
Simplify using the Douglas-Peucker algorithm ensuring that the result is a valid geometry.
static QgsAbstractGeometrySimplifier * createGeometrySimplifier(const QgsSimplifyMethod &simplifyMethod)
Creates a geometry simplifier according to specified method.
Implementation of GeometrySimplifier using the Douglas-Peucker algorithm.
#define QgsDebugMsg(str)
Definition: qgslogger.h:38