Implementation of a geometry simplifier using the "MapToPixel" algorithm. More...

#include <qgsmaptopixelgeometrysimplifier.h>

Inheritance diagram for QgsMapToPixelSimplifier:

Public Types
enum	SimplifyFlag { NoFlags = 0 , SimplifyGeometry = 1 , SimplifyEnvelope = 2 }
	Applicable simplification flags. More...

Public Member Functions
	QgsMapToPixelSimplifier (int simplifyFlags, double tolerance, Qgis::VectorSimplificationAlgorithm simplifyAlgorithm=Qgis::VectorSimplificationAlgorithm::Distance)
	Constructor.
bool	isGeneralizableByMapBoundingBox (const QgsRectangle &envelope) const
	Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context.
void	setSimplifyAlgorithm (Qgis::VectorSimplificationAlgorithm simplifyAlgorithm)
	Sets the local simplification algorithm of the vector layer managed.
void	setSimplifyFlags (int simplifyFlags)
	Sets the simplification hints of the vector layer managed.
void	setTolerance (double value)
	Sets the tolerance of the vector layer managed.
QgsAbstractGeometry *	simplify (const QgsAbstractGeometry *geometry) const override
	Returns a simplified version the specified geometry.
QgsGeometry	simplify (const QgsGeometry &geometry) const override
	Returns a simplified version the specified geometry.
Qgis::VectorSimplificationAlgorithm	simplifyAlgorithm () const
	Gets the local simplification algorithm of the vector layer managed.
int	simplifyFlags () const
	Gets the simplification hints of the vector layer managed.
Public Member Functions inherited from QgsAbstractGeometrySimplifier
virtual	~QgsAbstractGeometrySimplifier ()=default

Static Public Member Functions
static bool	isGeneralizableByMapBoundingBox (const QgsRectangle &envelope, double map2pixelTol)
	Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context.
Static Public Member Functions inherited from QgsAbstractGeometrySimplifier
static bool	isGeneralizableByDeviceBoundingBox (const QgsRectangle &envelope, float mapToPixelTol=1.0f)
	Returns whether the device-envelope can be replaced by its BBOX when is applied the specified tolerance.
static bool	isGeneralizableByDeviceBoundingBox (const QVector< QPointF > &points, float mapToPixelTol=1.0f)
	Returns whether the device-geometry can be replaced by its BBOX when is applied the specified tolerance.

Static Protected Member Functions
static float	calculateLengthSquared2D (double x1, double y1, double x2, double y2)
	Returns the squared 2D-distance of the vector defined by the two points specified.
static bool	equalSnapToGrid (double x1, double y1, double x2, double y2, double gridOriginX, double gridOriginY, float gridInverseSizeXY)
	Returns whether the points belong to the same grid.

Protected Attributes
Qgis::VectorSimplificationAlgorithm	mSimplifyAlgorithm = Qgis::VectorSimplificationAlgorithm::Distance
	Current algorithm.
int	mSimplifyFlags
	Current simplification flags.
double	mTolerance
	Distance tolerance for the simplification.

Detailed Description

Implementation of a geometry simplifier using the "MapToPixel" algorithm.

Simplifies a geometry removing points within of the maximum distance difference that defines the MapToPixel info of a RenderContext request. This class enables simplify the geometries to be rendered in a MapCanvas target to speed up the vector drawing.

Definition at line 41 of file qgsmaptopixelgeometrysimplifier.h.

Member Enumeration Documentation

◆ SimplifyFlag

enum QgsMapToPixelSimplifier::SimplifyFlag

Applicable simplification flags.

Enumerator
NoFlags	No simplification can be applied.
SimplifyGeometry	The geometries can be simplified using the current map2pixel context state.
SimplifyEnvelope	The geometries can be fully simplified by its BoundingBox.

Definition at line 49 of file qgsmaptopixelgeometrysimplifier.h.

Constructor & Destructor Documentation

◆ QgsMapToPixelSimplifier()

QgsMapToPixelSimplifier::QgsMapToPixelSimplifier	(	int	simplifyFlags,
		double	tolerance,
		Qgis::VectorSimplificationAlgorithm	simplifyAlgorithm = Qgis::VectorSimplificationAlgorithm::Distance )

Constructor.

Definition at line 29 of file qgsmaptopixelgeometrysimplifier.cpp.

Member Function Documentation

◆ calculateLengthSquared2D()

float QgsMapToPixelSimplifier::calculateLengthSquared2D	(	double	x1,
		double	y1,
		double	x2,
		double	y2 )

staticprotected

Returns the squared 2D-distance of the vector defined by the two points specified.

Definition at line 39 of file qgsmaptopixelgeometrysimplifier.cpp.

◆ equalSnapToGrid()

bool QgsMapToPixelSimplifier::equalSnapToGrid	(	double	x1,
		double	y1,
		double	x2,
		double	y2,
		double	gridOriginX,
		double	gridOriginY,
		float	gridInverseSizeXY )

staticprotected

Returns whether the points belong to the same grid.

Definition at line 47 of file qgsmaptopixelgeometrysimplifier.cpp.

◆ isGeneralizableByMapBoundingBox() [1/2]

bool QgsMapToPixelSimplifier::isGeneralizableByMapBoundingBox ( const QgsRectangle & envelope ) const

inline

Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context.

Definition at line 100 of file qgsmaptopixelgeometrysimplifier.h.

◆ isGeneralizableByMapBoundingBox() [2/2]

bool QgsMapToPixelSimplifier::isGeneralizableByMapBoundingBox	(	const QgsRectangle &	envelope,
		double	map2pixelTol )

static

Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context.

Definition at line 410 of file qgsmaptopixelgeometrysimplifier.cpp.

◆ setSimplifyAlgorithm()

void QgsMapToPixelSimplifier::setSimplifyAlgorithm ( Qgis::VectorSimplificationAlgorithm simplifyAlgorithm )

inline

Sets the local simplification algorithm of the vector layer managed.

Definition at line 85 of file qgsmaptopixelgeometrysimplifier.h.

◆ setSimplifyFlags()

void QgsMapToPixelSimplifier::setSimplifyFlags ( int simplifyFlags )

inline

Sets the simplification hints of the vector layer managed.

Definition at line 80 of file qgsmaptopixelgeometrysimplifier.h.

◆ setTolerance()

void QgsMapToPixelSimplifier::setTolerance ( double value )

inline

Sets the tolerance of the vector layer managed.

Definition at line 91 of file qgsmaptopixelgeometrysimplifier.h.

◆ simplify() [1/2]

QgsAbstractGeometry * QgsMapToPixelSimplifier::simplify ( const QgsAbstractGeometry * geometry ) const

overridevirtual

Returns a simplified version the specified geometry.

Will return nullptr if no simplification is to be performed to the geometry.

Caller takes ownership of the returned geometry.

Since: QGIS 3.18

Implements QgsAbstractGeometrySimplifier.

Definition at line 454 of file qgsmaptopixelgeometrysimplifier.cpp.

◆ simplify() [2/2]

QgsGeometry QgsMapToPixelSimplifier::simplify ( const QgsGeometry & geometry ) const

overridevirtual

Returns a simplified version the specified geometry.

Implements QgsAbstractGeometrySimplifier.

Definition at line 416 of file qgsmaptopixelgeometrysimplifier.cpp.

◆ simplifyAlgorithm()

Qgis::VectorSimplificationAlgorithm QgsMapToPixelSimplifier::simplifyAlgorithm ( ) const

inline

Gets the local simplification algorithm of the vector layer managed.

Definition at line 83 of file qgsmaptopixelgeometrysimplifier.h.

◆ simplifyFlags()

int QgsMapToPixelSimplifier::simplifyFlags ( ) const

inline

Gets the simplification hints of the vector layer managed.

Definition at line 78 of file qgsmaptopixelgeometrysimplifier.h.

Member Data Documentation

◆ mSimplifyAlgorithm

Qgis::VectorSimplificationAlgorithm QgsMapToPixelSimplifier::mSimplifyAlgorithm = Qgis::VectorSimplificationAlgorithm::Distance

protected

Current algorithm.

Definition at line 65 of file qgsmaptopixelgeometrysimplifier.h.

◆ mSimplifyFlags

int QgsMapToPixelSimplifier::mSimplifyFlags

protected

Current simplification flags.

Definition at line 62 of file qgsmaptopixelgeometrysimplifier.h.

◆ mTolerance

double QgsMapToPixelSimplifier::mTolerance

protected

Distance tolerance for the simplification.

Definition at line 68 of file qgsmaptopixelgeometrysimplifier.h.

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

/build/qgis-3.99.0+git20251210+2fe06baccd8+99sid/src/core/qgsmaptopixelgeometrysimplifier.h
/build/qgis-3.99.0+git20251210+2fe06baccd8+99sid/src/core/qgsmaptopixelgeometrysimplifier.cpp

Public Types

Public Member Functions

Static Public Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ SimplifyFlag

Constructor & Destructor Documentation

◆ QgsMapToPixelSimplifier()

Member Function Documentation

◆ calculateLengthSquared2D()

◆ equalSnapToGrid()

◆ isGeneralizableByMapBoundingBox() [1/2]

◆ isGeneralizableByMapBoundingBox() [2/2]

◆ setSimplifyAlgorithm()

◆ setSimplifyFlags()

◆ setTolerance()

◆ simplify() [1/2]

◆ simplify() [2/2]

◆ simplifyAlgorithm()

◆ simplifyFlags()

Member Data Documentation

◆ mSimplifyAlgorithm

◆ mSimplifyFlags

◆ mTolerance