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

#include <qgsmaptopixelgeometrysimplifier.h>

Inheritance diagram for QgsMapToPixelSimplifier:

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

Static Public Member Functions
static bool	canbeGeneralizedByMapBoundingBox (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	canbeGeneralizedByDeviceBoundingBox (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	canbeGeneralizedByDeviceBoundingBox (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.

Static Private Member Functions
static bool	simplifyWkbGeometry (int simplifyFlags, QGis::WkbType wkbType, unsigned char sourceWkb, size_t sourceWkbSize, unsigned char targetWkb, size_t &targetWkbSize, const QgsRectangle &envelope, double map2pixelTol, bool writeHeader=true, bool isaLinearRing=false)
	Simplify the WKB-geometry using the specified tolerance.

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

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 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 26 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 34 of file qgsmaptopixelgeometrysimplifier.cpp.

Referenced by simplifyWkbGeometry().

bool QgsMapToPixelSimplifier::canbeGeneralizedByMapBoundingBox	(	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 314 of file qgsmaptopixelgeometrysimplifier.cpp.

References QgsRectangle::xMaximum(), QgsRectangle::xMinimum(), QgsRectangle::yMaximum(), and QgsRectangle::yMinimum().

bool QgsMapToPixelSimplifier::canbeGeneralizedByMapBoundingBox ( 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.

References canbeGeneralizedByMapBoundingBox().

Referenced by canbeGeneralizedByMapBoundingBox().

void QgsMapToPixelSimplifier::setSimplifyFlags ( int simplifyFlags )

inline

Definition at line 62 of file qgsmaptopixelgeometrysimplifier.h.

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

virtual

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 325 of file qgsmaptopixelgeometrysimplifier.cpp.

References QgsGeometry::asWkb(), QgsGeometry::fromWkb(), mSimplifyFlags, mTolerance, simplifyGeometry(), and QgsGeometry::wkbSize().

int QgsMapToPixelSimplifier::simplifyFlags ( ) const

inline

Definition at line 61 of file qgsmaptopixelgeometrysimplifier.h.

bool QgsMapToPixelSimplifier::simplifyGeometry ( QgsGeometry * geometry ) const

virtual

Simplifies the specified geometry.

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

Implements QgsAbstractGeometrySimplifier.

Definition at line 365 of file qgsmaptopixelgeometrysimplifier.cpp.

References mSimplifyFlags, and mTolerance.

Referenced by simplify().

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 339 of file qgsmaptopixelgeometrysimplifier.cpp.

References QgsGeometry::asWkb(), QgsGeometry::boundingBox(), QgsGeometry::fromWkb(), QGis::Line, QGis::Polygon, simplifyWkbGeometry(), QgsGeometry::type(), QgsGeometry::wkbSize(), and QgsGeometry::wkbType().

bool QgsMapToPixelSimplifier::simplifyWkbGeometry	(	int	simplifyFlags,
		QGis::WkbType	wkbType,
		unsigned char *	sourceWkb,
		size_t	sourceWkbSize,
		unsigned char *	targetWkb,
		size_t &	targetWkbSize,
		const QgsRectangle &	envelope,
		double	map2pixelTol,
		bool	writeHeader = `true`,
		bool	isaLinearRing = `false`
	)