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QgsMapToPixelSimplifier Class Reference

Implementation of GeometrySimplifier using the "MapToPixel" algorithm. More...

#include <qgsmaptopixelgeometrysimplifier.h>

Inheritance diagram for QgsMapToPixelSimplifier:
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Public Types

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

Public Member Functions

 QgsMapToPixelSimplifier (int simplifyFlags, double tolerance)
virtual ~QgsMapToPixelSimplifier ()
bool isGeneralizableByMapBoundingBox (const QgsRectangle &envelope) const
 Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context.
void setSimplifyFlags (int simplifyFlags)
virtual QgsGeometrysimplify (QgsGeometry *geometry) const override
 Returns a simplified version the specified geometry.
int simplifyFlags () const
virtual bool simplifyGeometry (QgsGeometry *geometry) const override
 Simplifies the specified geometry.
- Public Member Functions inherited from QgsAbstractGeometrySimplifier
virtual ~QgsAbstractGeometrySimplifier ()

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 bool simplifyGeometry (QgsGeometry *geometry, int simplifyFlags, double tolerance)
 Simplifies the geometry 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.

Protected Attributes

int mSimplifyFlags
 Current simplification flags.
double mTolerance
 Distance tolerance for the simplification.

Detailed Description

Implementation of GeometrySimplifier 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 32 of file qgsmaptopixelgeometrysimplifier.h.

Member Enumeration Documentation

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 39 of file qgsmaptopixelgeometrysimplifier.h.

Constructor & Destructor Documentation

QgsMapToPixelSimplifier::QgsMapToPixelSimplifier ( int  simplifyFlags,
double  tolerance 
)

Definition at line 21 of file qgsmaptopixelgeometrysimplifier.cpp.

QgsMapToPixelSimplifier::~QgsMapToPixelSimplifier ( )
virtual

Definition at line 27 of file qgsmaptopixelgeometrysimplifier.cpp.

Member Function Documentation

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 35 of file qgsmaptopixelgeometrysimplifier.cpp.

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 398 of file qgsmaptopixelgeometrysimplifier.cpp.

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 76 of file qgsmaptopixelgeometrysimplifier.h.

void QgsMapToPixelSimplifier::setSimplifyFlags ( int  simplifyFlags)
inline

Definition at line 62 of file qgsmaptopixelgeometrysimplifier.h.

QgsGeometry * QgsMapToPixelSimplifier::simplify ( QgsGeometry geometry) const
overridevirtual

Returns a simplified version the specified geometry.

Returns a simplified version the specified geometry (Removing duplicated points) when is applied the specified map2pixel context.

Implements QgsAbstractGeometrySimplifier.

Definition at line 405 of file qgsmaptopixelgeometrysimplifier.cpp.

int QgsMapToPixelSimplifier::simplifyFlags ( ) const
inline

Definition at line 61 of file qgsmaptopixelgeometrysimplifier.h.

bool QgsMapToPixelSimplifier::simplifyGeometry ( QgsGeometry geometry) const
overridevirtual

Simplifies the specified geometry.

Simplifies the geometry (Removing duplicated points) when is applied the specified map2pixel context.

Implements QgsAbstractGeometrySimplifier.

Definition at line 446 of file qgsmaptopixelgeometrysimplifier.cpp.

bool QgsMapToPixelSimplifier::simplifyGeometry ( QgsGeometry geometry,
int  simplifyFlags,
double  tolerance 
)
static

Simplifies the geometry when is applied the specified map2pixel context.

Simplifies the geometry (Removing duplicated points) when is applied the specified map2pixel context.

Definition at line 419 of file qgsmaptopixelgeometrysimplifier.cpp.

Member Data Documentation

int QgsMapToPixelSimplifier::mSimplifyFlags
protected

Current simplification flags.

Definition at line 52 of file qgsmaptopixelgeometrysimplifier.h.

double QgsMapToPixelSimplifier::mTolerance
protected

Distance tolerance for the simplification.

Definition at line 55 of file qgsmaptopixelgeometrysimplifier.h.


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