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 , SnappedToGridGlobal = 3 }
	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 (SimplifyAlgorithm simplifyAlgorithm)
	Sets the local simplification algorithm of the vector layer managed. More...
void	setSimplifyHints (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. Represents the maximum distance in map units between two coordinates which can be considered equal. 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. Represents the maximum distance in map units between two coordinates which can be considered equal. More...

Detailed Description

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

Since

QGIS 2.2

Definition at line 29 of file qgsvectorsimplifymethod.h.

Member Enumeration Documentation

SimplifyAlgorithm

enum QgsVectorSimplifyMethod::SimplifyAlgorithm

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.
SnappedToGridGlobal	Snap to a global grid based on the tolerance. Good for consistent results for incoming vertices, regardless of their feature.

Definition at line 54 of file qgsvectorsimplifymethod.h.

SimplifyHint

enum QgsVectorSimplifyMethod::SimplifyHint

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 37 of file qgsvectorsimplifymethod.h.

Constructor & Destructor Documentation

QgsVectorSimplifyMethod()

QgsVectorSimplifyMethod::QgsVectorSimplifyMethod

(

)

construct a default object

Definition at line 19 of file qgsvectorsimplifymethod.cpp.

Member Function Documentation

forceLocalOptimization()

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 81 of file qgsvectorsimplifymethod.h.

maximumScale()

float QgsVectorSimplifyMethod::maximumScale ( ) const

inline

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

Definition at line 86 of file qgsvectorsimplifymethod.h.

setForceLocalOptimization()

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 79 of file qgsvectorsimplifymethod.h.

setMaximumScale()

void QgsVectorSimplifyMethod::setMaximumScale ( float  maximumScale )

inline

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

Definition at line 84 of file qgsvectorsimplifymethod.h.

setSimplifyAlgorithm()

void QgsVectorSimplifyMethod::setSimplifyAlgorithm ( SimplifyAlgorithm  simplifyAlgorithm )

inline

Sets the local simplification algorithm of the vector layer managed.

Definition at line 64 of file qgsvectorsimplifymethod.h.

setSimplifyHints()

void QgsVectorSimplifyMethod::setSimplifyHints ( SimplifyHints  simplifyHints )

inline

Sets the simplification hints of the vector layer managed.

Definition at line 49 of file qgsvectorsimplifymethod.h.

setThreshold()

void QgsVectorSimplifyMethod::setThreshold ( float  threshold )

inline

Sets the simplification threshold of the vector layer managed.

Definition at line 74 of file qgsvectorsimplifymethod.h.

setTolerance()

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 69 of file qgsvectorsimplifymethod.h.

simplifyAlgorithm()

SimplifyAlgorithm QgsVectorSimplifyMethod::simplifyAlgorithm ( ) const

inline

Gets the local simplification algorithm of the vector layer managed.

Definition at line 66 of file qgsvectorsimplifymethod.h.

simplifyHints()

SimplifyHints QgsVectorSimplifyMethod::simplifyHints ( ) const

inline

Gets the simplification hints of the vector layer managed.

Definition at line 51 of file qgsvectorsimplifymethod.h.

threshold()

float QgsVectorSimplifyMethod::threshold ( ) const

inline

Gets the simplification threshold of the vector layer managed.

Definition at line 76 of file qgsvectorsimplifymethod.h.

tolerance()

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 71 of file qgsvectorsimplifymethod.h.

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

• /build/qgis-3.18.1+99unstable/src/core/qgsvectorsimplifymethod.h
• /build/qgis-3.18.1+99unstable/src/core/qgsvectorsimplifymethod.cpp