QGIS API Documentation  2.17.0-Master (872e6d2)
Public Types | Public Member Functions | List of all members
QgsVectorSimplifyMethod Class Reference

This class contains information how to simplify geometries fetched from a vector layer. More...

#include <qgsvectorsimplifymethod.h>

Public Types

enum  SimplifyAlgorithm { Distance = 0, SnapToGrid = 1, Visvalingam = 2 }
 Types of local simplification algorithms that can be used. More...
 
enum  SimplifyHint { NoSimplification = 0, GeometrySimplification = 1, AntialiasingSimplification = 2, FullSimplification = 3 }
 Simplification flags for fast rendering of features. More...
 

Public Member Functions

 QgsVectorSimplifyMethod ()
 construct a default object More...
 
bool forceLocalOptimization () const
 Gets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries. More...
 
float maximumScale () const
 Gets the maximum scale at which the layer should be simplified. More...
 
void setForceLocalOptimization (bool localOptimization)
 Sets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries. More...
 
void setMaximumScale (float maximumScale)
 Sets the maximum scale at which the layer should be simplified. More...
 
void setSimplifyAlgorithm (const SimplifyAlgorithm &simplifyAlgorithm)
 Sets the local simplification algorithm of the vector layer managed. More...
 
void setSimplifyHints (const SimplifyHints &simplifyHints)
 Sets the simplification hints of the vector layer managed. More...
 
void setThreshold (float threshold)
 Sets the simplification threshold of the vector layer managed. More...
 
void setTolerance (double tolerance)
 Sets the tolerance of simplification in map units. More...
 
SimplifyAlgorithm simplifyAlgorithm () const
 Gets the local simplification algorithm of the vector layer managed. More...
 
SimplifyHints simplifyHints () const
 Gets the simplification hints of the vector layer managed. More...
 
float threshold () const
 Gets the simplification threshold of the vector layer managed. More...
 
double tolerance () const
 Gets the tolerance of simplification in map units. More...
 

Detailed Description

This class contains information how to simplify geometries fetched from a vector layer.

Note
added in 2.2

Definition at line 25 of file qgsvectorsimplifymethod.h.

Member Enumeration Documentation

Types of local simplification algorithms that can be used.

Enumerator
Distance 

The simplification uses the distance between points to remove duplicate points.

SnapToGrid 

The simplification uses a grid (similar to ST_SnapToGrid) to remove duplicate points.

Visvalingam 

The simplification gives each point in a line an importance weighting, so that least important points are removed first.

Definition at line 47 of file qgsvectorsimplifymethod.h.

Simplification flags for fast rendering of features.

Enumerator
NoSimplification 

No simplification can be applied.

GeometrySimplification 

The geometries can be simplified using the current map2pixel context state.

AntialiasingSimplification 

The geometries can be rendered with 'AntiAliasing' disabled because of it is '1-pixel size'.

FullSimplification 

All simplification hints can be applied ( Geometry + AA-disabling )

Definition at line 32 of file qgsvectorsimplifymethod.h.

Constructor & Destructor Documentation

QgsVectorSimplifyMethod::QgsVectorSimplifyMethod ( )

construct a default object

Definition at line 20 of file qgsvectorsimplifymethod.cpp.

Member Function Documentation

bool QgsVectorSimplifyMethod::forceLocalOptimization ( ) const
inline

Gets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries.

Definition at line 72 of file qgsvectorsimplifymethod.h.

float QgsVectorSimplifyMethod::maximumScale ( ) const
inline

Gets the maximum scale at which the layer should be simplified.

Definition at line 77 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setForceLocalOptimization ( bool  localOptimization)
inline

Sets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries.

Definition at line 70 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setMaximumScale ( float  maximumScale)
inline

Sets the maximum scale at which the layer should be simplified.

Definition at line 75 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setSimplifyAlgorithm ( const SimplifyAlgorithm simplifyAlgorithm)
inline

Sets the local simplification algorithm of the vector layer managed.

Definition at line 55 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setSimplifyHints ( const SimplifyHints &  simplifyHints)
inline

Sets the simplification hints of the vector layer managed.

Definition at line 42 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setThreshold ( float  threshold)
inline

Sets the simplification threshold of the vector layer managed.

Definition at line 65 of file qgsvectorsimplifymethod.h.

void QgsVectorSimplifyMethod::setTolerance ( double  tolerance)
inline

Sets the tolerance of simplification in map units.

Represents the maximum distance in map units between two coordinates which can be considered equal

Definition at line 60 of file qgsvectorsimplifymethod.h.

SimplifyAlgorithm QgsVectorSimplifyMethod::simplifyAlgorithm ( ) const
inline

Gets the local simplification algorithm of the vector layer managed.

Definition at line 57 of file qgsvectorsimplifymethod.h.

SimplifyHints QgsVectorSimplifyMethod::simplifyHints ( ) const
inline

Gets the simplification hints of the vector layer managed.

Definition at line 44 of file qgsvectorsimplifymethod.h.

float QgsVectorSimplifyMethod::threshold ( ) const
inline

Gets the simplification threshold of the vector layer managed.

Definition at line 67 of file qgsvectorsimplifymethod.h.

double QgsVectorSimplifyMethod::tolerance ( ) const
inline

Gets the tolerance of simplification in map units.

Represents the maximum distance in map units between two coordinates which can be considered equal

Definition at line 62 of file qgsvectorsimplifymethod.h.


The documentation for this class was generated from the following files: