LabelPosition is a candidate feature label position. More...

#include <labelposition.h>

Inheritance diagram for pal::LabelPosition:

Public Types
enum	Quadrant { QuadrantAboveLeft , QuadrantAbove , QuadrantAboveRight , QuadrantLeft , QuadrantOver , QuadrantRight , QuadrantBelowLeft , QuadrantBelow , QuadrantBelowRight }
	Position of label candidate relative to feature. More...

Public Member Functions
	LabelPosition (const LabelPosition &other)
	Copy constructor.

	LabelPosition (int id, double x1, double y1, double w, double h, double alpha, double cost, FeaturePart *feature, bool isReversed=false, Quadrant quadrant=QuadrantOver)
	create a new LabelPosition

	~LabelPosition () override

double	angleDifferential ()
	Returns the angle differential of all LabelPosition parts.

bool	conflictsWithObstacle () const
	Returns whether the position is marked as conflicting with an obstacle feature.

double	cost () const
	Returns the candidate label position's geographical cost.

bool	crossesBoundary (PointSet *polygon) const
	Returns `true` if this label crosses the boundary of the specified polygon.

bool	crossesLine (PointSet *line) const
	Returns `true` if this label crosses the specified line.

void	decrementNumOverlaps ()
	Decreases the number of overlaps recorded against this position by 1.

double	getAlpha () const
	Returns the angle to rotate text (in radians).

void	getBoundingBox (double amin[2], double amax[2]) const
	Returns bounding box - amin: xmin,ymin - amax: xmax,ymax.

double	getDistanceToPoint (double xp, double yp, bool useOuterBounds) const
	Gets distance from this label to a point.

FeaturePart *	getFeaturePart () const
	Returns the feature corresponding to this labelposition.

double	getHeight () const

int	getId () const
	Returns the id.

int	getNumOverlaps () const

int	getPartId () const

int	getProblemFeatureId () const

Quadrant	getQuadrant () const

bool	getReversed () const

bool	getUpsideDown () const

double	getWidth () const

double	getX (int i=0) const
	Returns the down-left x coordinate.

double	getY (int i=0) const
	Returns the down-left y coordinate.

unsigned int	globalId () const
	Returns the global ID for the candidate, which is unique for a single run of the pal labelling engine.

bool	hasHardObstacleConflict () const
	Returns whether the position is marked as having a hard conflict with an obstacle feature.

void	incrementNumOverlaps ()
	Increases the number of overlaps recorded against this position by 1.

void	insertIntoIndex (PalRtree< LabelPosition > &index)
	Inserts the label position into the specified index.

bool	intersects (const GEOSPreparedGeometry *geometry)
	Returns `true` if the label position intersects a geometry.

bool	intersectsWithPolygon (PointSet *polygon) const
	Returns `true` if any intersection between polygon and position exists.

bool	isInConflict (const LabelPosition *ls) const
	Check whether or not this overlap with another labelPosition.

LabelPosition *	nextPart () const
	Returns the next part of this label position (i.e.

bool	outerBoundingBoxIntersects (const LabelPosition *other) const
	Returns `true` if the outer bounding box of this pointset intersects the outer bounding box of another label position.

int	polygonIntersectionCost (PointSet *polygon) const
	Returns cost of position intersection with polygon (testing area of intersection and center).

const GEOSPreparedGeometry *	preparedMultiPartGeom () const
	Returns a prepared GEOS representation of all label parts as a multipolygon.

const GEOSPreparedGeometry *	preparedOuterBoundsGeom () const
	Returns the prepared outer boundary geometry.

void	removeFromIndex (PalRtree< LabelPosition > &index)
	Removes the label position from the specified index.

void	resetNumOverlaps ()

void	setConflictsWithObstacle (bool conflicts)
	Sets whether the position is marked as conflicting with an obstacle feature.

void	setCost (double newCost)
	Sets the candidate label position's geographical cost.

void	setGlobalId (unsigned int id)
	Sets the global id for the candidate, which is unique for a single run of the pal labelling engine.

void	setHasHardObstacleConflict (bool conflicts)
	Sets whether the position is marked as having a hard conflict with an obstacle feature.

void	setNextPart (std::unique_ptr< LabelPosition > next)
	Sets the next part of this label position (i.e.

void	setPartId (int id)

void	setProblemIds (int probFid, int lpId)
	Set problem feature ID and assigned label candidate ID.

void	setUpsideDownCharCount (int count)
	Sets the count of upside down characters for this label position.

int	upsideDownCharCount () const
	Returns the number of upside down characters for this label position.

void	validateCost ()
	Make sure the cost is less than 1.

bool	within (const GEOSPreparedGeometry *geometry)
	Returns `true` if the label position is within a geometry.

Public Member Functions inherited from pal::PointSet
	PointSet ()

	PointSet (int nbPoints, double x, double y)

virtual	~PointSet ()

double	area () const
	Returns area of polygon geometry.

QgsRectangle	boundingBox () const
	Returns the point set bounding box.

bool	boundingBoxIntersects (const PointSet *other) const
	Returns `true` if the bounding box of this pointset intersects the bounding box of another pointset.

std::unique_ptr< PointSet >	clone () const
	Returns a copy of the point set.

OrientedConvexHullBoundingBox	computeConvexHullOrientedBoundingBox (bool &ok)
	Computes an oriented bounding box for the shape's convex hull.

bool	containsLabelCandidate (double x, double y, double width, double height, double alpha=0) const
	Tests whether a possible label candidate will fit completely within the shape.

bool	containsPoint (double x, double y) const
	Tests whether point set contains a specified point.

std::tuple< std::vector< double >, double >	edgeDistances () const
	Returns a vector of edge distances as well as its total length.

void	extendLineByDistance (double startDistance, double endDistance, double smoothDistance)
	Extends linestrings by the specified amount at the start and end of the line, by extending the existing lines following the same direction as the original line start or end.

std::unique_ptr< PointSet >	extractShape (int nbPtSh, int imin, int imax, int fps, int fpe, double fptx, double fpty)
	Does... something completely inscrutable.

const GEOSGeometry *	geos () const
	Returns the point set's GEOS geometry.

void	getCentroid (double &px, double &py, bool forceInside=false) const

int	getGeosType () const

PointSet *	getHoleOf () const
	Returns `nullptr` if this isn't a hole. Otherwise returns pointer to parent pointset.

int	getNumPoints () const

void	getPointByDistance (double d, double ad, double dl, double px, double py) const
	Gets a point a set distance along a line geometry.

geos::unique_ptr	interpolatePoint (double distance) const
	Returns a GEOS geometry representing the point interpolated on the shape by distance.

bool	isClosed () const
	Returns `true` if pointset is closed.

double	length () const
	Returns length of line geometry.

double	lineLocatePoint (const GEOSGeometry *point) const
	Returns the distance along the geometry closest to the specified GEOS point.

double	minDistanceToPoint (double px, double py, double rx=nullptr, double ry=nullptr) const
	Returns the squared minimum distance between the point set geometry and the point (px,py) Optionally, the nearest point is stored in (rx,ry).

void	offsetCurveByDistance (double distance)
	Offsets linestrings by the specified distance.

QString	toWkt () const
	Returns a WKT representation of the point set.

Protected Attributes
double	alpha
	Rotation in radians.

FeaturePart *	feature = nullptr

double	h

int	id

int	nbOverlap

int	partId

int	probFeat

LabelPosition::Quadrant	quadrant

bool	reversed

bool	upsideDown

double	w

Protected Attributes inherited from pal::PointSet
std::vector< int >	convexHull

PointSet *	holeOf = nullptr

double	mArea = -1

GEOSGeometry *	mGeos = nullptr

double	mLength = -1

bool	mOwnsGeom = false

PointSet *	parent = nullptr

int	type

double	xmax = std::numeric_limits<double>::lowest()

double	xmin = std::numeric_limits<double>::max()

double	ymax = std::numeric_limits<double>::lowest()

double	ymin = std::numeric_limits<double>::max()

Friends
class	CostCalculator

class	PolygonCostCalculator

Additional Inherited Members
Static Public Member Functions inherited from pal::PointSet
static QLinkedList< PointSet * >	splitPolygons (PointSet *inputShape, double labelWidth, double labelHeight)
	Split a polygon using some random logic into some other polygons.

Public Attributes inherited from pal::PointSet
int	nbPoints

std::vector< double >	x

std::vector< double >	y

Protected Member Functions inherited from pal::PointSet
	PointSet (const PointSet &ps)

	PointSet (double x, double y)

void	createGeosGeom () const

void	deleteCoords ()

void	invalidateGeos () const

const GEOSPreparedGeometry *	preparedGeom () const

Detailed Description

LabelPosition is a candidate feature label position.

Note: not available in Python bindings

Definition at line 55 of file labelposition.h.

Member Enumeration Documentation

◆ Quadrant

enum pal::LabelPosition::Quadrant

Position of label candidate relative to feature.

Enumerator
QuadrantAboveLeft
QuadrantAbove
QuadrantAboveRight
QuadrantLeft
QuadrantOver
QuadrantRight
QuadrantBelowLeft
QuadrantBelow
QuadrantBelowRight

Definition at line 65 of file labelposition.h.

Constructor & Destructor Documentation

◆ LabelPosition() [1/2]

LabelPosition::LabelPosition	(	int	id,
		double	x1,
		double	y1,
		double	w,
		double	h,
		double	alpha,
		double	cost,
		FeaturePart *	feature,
		bool	isReversed = `false`,
		Quadrant	quadrant = `QuadrantOver`
	)

create a new LabelPosition

Parameters

id	id of this labelposition
x1	down-left x coordinate
y1	down-left y coordinate
w	label width
h	label height
alpha	rotation in radians
cost	geographic cost
feature	labelpos owners
isReversed	label is reversed
quadrant	relative position of label to feature

Definition at line 43 of file labelposition.cpp.

◆ LabelPosition() [2/2]

LabelPosition::LabelPosition ( const LabelPosition & other )

Copy constructor.

Definition at line 142 of file labelposition.cpp.

◆ ~LabelPosition()

LabelPosition::~LabelPosition ( )

override

Definition at line 168 of file labelposition.cpp.

Member Function Documentation

◆ angleDifferential()

double LabelPosition::angleDifferential ( )

Returns the angle differential of all LabelPosition parts.

Definition at line 813 of file labelposition.cpp.

◆ conflictsWithObstacle()

bool pal::LabelPosition::conflictsWithObstacle ( ) const

inline

Returns whether the position is marked as conflicting with an obstacle feature.

See also: setConflictsWithObstacle

Definition at line 236 of file labelposition.h.

◆ cost()

double pal::LabelPosition::cost ( ) const

inline

Returns the candidate label position's geographical cost.

See also: setCost

Definition at line 215 of file labelposition.h.

◆ crossesBoundary()

bool LabelPosition::crossesBoundary ( PointSet * polygon ) const

Returns true if this label crosses the boundary of the specified polygon.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 680 of file labelposition.cpp.

◆ crossesLine()

bool LabelPosition::crossesLine ( PointSet * line ) const

Returns true if this label crosses the specified line.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 649 of file labelposition.cpp.

◆ decrementNumOverlaps()

void pal::LabelPosition::decrementNumOverlaps ( )

inline

Decreases the number of overlaps recorded against this position by 1.

Definition at line 196 of file labelposition.h.

◆ getAlpha()

double LabelPosition::getAlpha ( ) const

Returns the angle to rotate text (in radians).

Definition at line 392 of file labelposition.cpp.

◆ getBoundingBox()

void LabelPosition::getBoundingBox	(	double	amin[2],
		double	amax[2]
	)		const

Returns bounding box - amin: xmin,ymin - amax: xmax,ymax.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 410 of file labelposition.cpp.

◆ getDistanceToPoint()

double LabelPosition::getDistanceToPoint	(	double	xp,
		double	yp,
		bool	useOuterBounds
	)		const

Gets distance from this label to a point.

If point lies inside, returns negative number.

If useOuterBounds is true then the distance will be calculated to the outer bounds of the label (see QgsLabelFeature::outerBounds()), otherwise it will be calculated to the label's actual rectangle.

Definition at line 548 of file labelposition.cpp.

◆ getFeaturePart()

FeaturePart * LabelPosition::getFeaturePart ( ) const

Returns the feature corresponding to this labelposition.

Definition at line 405 of file labelposition.cpp.

◆ getHeight()

double pal::LabelPosition::getHeight ( ) const

inline

Definition at line 270 of file labelposition.h.

◆ getId()

int LabelPosition::getId ( ) const

Returns the id.

Definition at line 377 of file labelposition.cpp.

◆ getNumOverlaps()

int pal::LabelPosition::getNumOverlaps ( ) const

inline

Definition at line 185 of file labelposition.h.

◆ getPartId()

int pal::LabelPosition::getPartId ( ) const

inline

Definition at line 297 of file labelposition.h.

◆ getProblemFeatureId()

int pal::LabelPosition::getProblemFeatureId ( ) const

inline

Definition at line 198 of file labelposition.h.

◆ getQuadrant()

Quadrant pal::LabelPosition::getQuadrant ( ) const

inline

Definition at line 280 of file labelposition.h.

◆ getReversed()

bool pal::LabelPosition::getReversed ( ) const

inline

Definition at line 277 of file labelposition.h.

◆ getUpsideDown()

bool pal::LabelPosition::getUpsideDown ( ) const

inline

Definition at line 278 of file labelposition.h.

◆ getWidth()

double pal::LabelPosition::getWidth ( ) const

inline

Definition at line 269 of file labelposition.h.

◆ getX()

double LabelPosition::getX ( int i = 0 ) const

Returns the down-left x coordinate.

See also: getY()

Definition at line 382 of file labelposition.cpp.

◆ getY()

double LabelPosition::getY ( int i = 0 ) const

Returns the down-left y coordinate.

See also: getX()

Definition at line 387 of file labelposition.cpp.

◆ globalId()

unsigned int pal::LabelPosition::globalId ( ) const

inline

Returns the global ID for the candidate, which is unique for a single run of the pal labelling engine.

A return value of 0 means that the ID has not been assigned.

See also: setGlobalId()

Definition at line 346 of file labelposition.h.

◆ hasHardObstacleConflict()

bool pal::LabelPosition::hasHardObstacleConflict ( ) const

inline

Returns whether the position is marked as having a hard conflict with an obstacle feature.

A hard conflict means that the placement should (usually) not be considered, because the candidate conflicts with a obstacle of sufficient weight.

See also: setHasHardObstacleConflict()

Definition at line 252 of file labelposition.h.

◆ incrementNumOverlaps()

void pal::LabelPosition::incrementNumOverlaps ( )

inline

Increases the number of overlaps recorded against this position by 1.

Definition at line 191 of file labelposition.h.

◆ insertIntoIndex()

void LabelPosition::insertIntoIndex ( PalRtree< LabelPosition > & index )

Inserts the label position into the specified index.

Definition at line 497 of file labelposition.cpp.

◆ intersects()

bool LabelPosition::intersects ( const GEOSPreparedGeometry * geometry )

Returns true if the label position intersects a geometry.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 177 of file labelposition.cpp.

◆ intersectsWithPolygon()

bool LabelPosition::intersectsWithPolygon ( PointSet * polygon ) const

Returns true if any intersection between polygon and position exists.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 720 of file labelposition.cpp.

◆ isInConflict()

bool LabelPosition::isInConflict ( const LabelPosition * ls ) const

Check whether or not this overlap with another labelPosition.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Parameters

ls	other labelposition

Returns: true or false

Definition at line 231 of file labelposition.cpp.

◆ nextPart()

LabelPosition * pal::LabelPosition::nextPart ( ) const

inline

Returns the next part of this label position (i.e.

the next character for a curved label).

See also: setNextPart()

Definition at line 287 of file labelposition.h.

◆ outerBoundingBoxIntersects()

bool LabelPosition::outerBoundingBoxIntersects ( const LabelPosition * other ) const

Returns true if the outer bounding box of this pointset intersects the outer bounding box of another label position.

Definition at line 451 of file labelposition.cpp.

◆ polygonIntersectionCost()

int LabelPosition::polygonIntersectionCost ( PointSet * polygon ) const

Returns cost of position intersection with polygon (testing area of intersection and center).

Cost ranges between 0 and 12, with extra cost if center of label position is covered.

Definition at line 712 of file labelposition.cpp.

◆ preparedMultiPartGeom()

const GEOSPreparedGeometry * LabelPosition::preparedMultiPartGeom ( ) const

Returns a prepared GEOS representation of all label parts as a multipolygon.

Since: QGIS 3.20

Definition at line 531 of file labelposition.cpp.

◆ preparedOuterBoundsGeom()

const GEOSPreparedGeometry * LabelPosition::preparedOuterBoundsGeom ( ) const

Returns the prepared outer boundary geometry.

Since: QGIS 3.30

Definition at line 543 of file labelposition.cpp.

◆ removeFromIndex()

void LabelPosition::removeFromIndex ( PalRtree< LabelPosition > & index )

Removes the label position from the specified index.

Definition at line 489 of file labelposition.cpp.

◆ resetNumOverlaps()

void pal::LabelPosition::resetNumOverlaps ( )

inline

Definition at line 186 of file labelposition.h.

◆ setConflictsWithObstacle()

void LabelPosition::setConflictsWithObstacle ( bool conflicts )

Sets whether the position is marked as conflicting with an obstacle feature.

Parameters

conflicts set to true to mark candidate as being in conflict

Note: This method applies to all label parts for the candidate position.

See also: conflictsWithObstacle

Definition at line 475 of file labelposition.cpp.

◆ setCost()

void pal::LabelPosition::setCost ( double newCost )

inline

Sets the candidate label position's geographical cost.

Parameters

newCost new cost for position

See also: cost

Definition at line 222 of file labelposition.h.

◆ setGlobalId()

void pal::LabelPosition::setGlobalId ( unsigned int id )

inline

Sets the global id for the candidate, which is unique for a single run of the pal labelling engine.

See also: globalId()

Definition at line 354 of file labelposition.h.

◆ setHasHardObstacleConflict()

void LabelPosition::setHasHardObstacleConflict ( bool conflicts )

Sets whether the position is marked as having a hard conflict with an obstacle feature.

A hard conflict means that the placement should (usually) not be considered, because the candidate conflicts with a obstacle of sufficient weight.

See also: hasHardObstacleConflict()

Definition at line 482 of file labelposition.cpp.

◆ setNextPart()

void pal::LabelPosition::setNextPart ( std::unique_ptr< LabelPosition > next )

inline

Sets the next part of this label position (i.e.

the next character for a curved label).

See also: nextPart()

Definition at line 294 of file labelposition.h.

◆ setPartId()

void pal::LabelPosition::setPartId ( int id )

inline

Definition at line 298 of file labelposition.h.

◆ setProblemIds()

void pal::LabelPosition::setProblemIds	(	int	probFid,
		int	lpId
	)

inline

Set problem feature ID and assigned label candidate ID.

called from pal.cpp during extraction.

Definition at line 204 of file labelposition.h.

◆ setUpsideDownCharCount()

void pal::LabelPosition::setUpsideDownCharCount ( int count )

inline

Sets the count of upside down characters for this label position.

See also: upsideDownCharCount()

Definition at line 305 of file labelposition.h.

◆ upsideDownCharCount()

int pal::LabelPosition::upsideDownCharCount ( ) const

inline

Returns the number of upside down characters for this label position.

See also: setUpsideDownCharCount()

Definition at line 312 of file labelposition.h.

◆ validateCost()

void LabelPosition::validateCost ( )

Make sure the cost is less than 1.

Definition at line 397 of file labelposition.cpp.

◆ within()

bool LabelPosition::within ( const GEOSPreparedGeometry * geometry )

Returns true if the label position is within a geometry.

Note: This method considers the label's outer bounds (see QgsLabelFeature::outerBounds())

Definition at line 204 of file labelposition.cpp.

Friends And Related Symbol Documentation

◆ CostCalculator

friend class CostCalculator

friend

Definition at line 57 of file labelposition.h.

◆ PolygonCostCalculator

friend class PolygonCostCalculator

friend

Definition at line 58 of file labelposition.h.

Member Data Documentation

◆ alpha

double pal::LabelPosition::alpha

protected

Rotation in radians.

Definition at line 373 of file labelposition.h.

◆ feature

FeaturePart* pal::LabelPosition::feature = nullptr

protected

Definition at line 365 of file labelposition.h.

◆ h

double pal::LabelPosition::h

protected

Definition at line 376 of file labelposition.h.

◆ id

int pal::LabelPosition::id

protected

Definition at line 363 of file labelposition.h.

◆ nbOverlap

int pal::LabelPosition::nbOverlap

protected

Definition at line 370 of file labelposition.h.

◆ partId

int pal::LabelPosition::partId

protected

Definition at line 378 of file labelposition.h.

◆ probFeat

int pal::LabelPosition::probFeat

protected

Definition at line 368 of file labelposition.h.

◆ quadrant

LabelPosition::Quadrant pal::LabelPosition::quadrant

protected

Definition at line 387 of file labelposition.h.

◆ reversed

bool pal::LabelPosition::reversed

protected

Definition at line 383 of file labelposition.h.

◆ upsideDown

bool pal::LabelPosition::upsideDown

protected

Definition at line 385 of file labelposition.h.

◆ w

double pal::LabelPosition::w

protected

Definition at line 375 of file labelposition.h.

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

/build/qgis-3.36.0+99sid/src/core/pal/labelposition.h
/build/qgis-3.36.0+99sid/src/core/pal/labelposition.cpp

Public Types

Public Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ Quadrant

Constructor & Destructor Documentation

◆ LabelPosition() [1/2]

◆ LabelPosition() [2/2]

◆ ~LabelPosition()

Member Function Documentation

◆ angleDifferential()

◆ conflictsWithObstacle()

◆ cost()

◆ crossesBoundary()

◆ crossesLine()

◆ decrementNumOverlaps()

◆ getAlpha()

◆ getBoundingBox()

◆ getDistanceToPoint()

◆ getFeaturePart()

◆ getHeight()

◆ getId()

◆ getNumOverlaps()

◆ getPartId()

◆ getProblemFeatureId()

◆ getQuadrant()

◆ getReversed()

◆ getUpsideDown()

◆ getWidth()

◆ getX()

◆ getY()

◆ globalId()

◆ hasHardObstacleConflict()

◆ incrementNumOverlaps()

◆ insertIntoIndex()

◆ intersects()

◆ intersectsWithPolygon()

◆ isInConflict()

◆ nextPart()

◆ outerBoundingBoxIntersects()

◆ polygonIntersectionCost()

◆ preparedMultiPartGeom()

◆ preparedOuterBoundsGeom()

◆ removeFromIndex()

◆ resetNumOverlaps()

◆ setConflictsWithObstacle()

◆ setCost()

◆ setGlobalId()

◆ setHasHardObstacleConflict()

◆ setNextPart()

◆ setPartId()

◆ setProblemIds()

◆ setUpsideDownCharCount()

◆ upsideDownCharCount()

◆ validateCost()

◆ within()

Friends And Related Symbol Documentation

◆ CostCalculator

◆ PolygonCostCalculator

Member Data Documentation

◆ alpha

◆ feature

◆ h

◆ id

◆ nbOverlap

◆ partId

◆ probFeat

◆ quadrant

◆ reversed

◆ upsideDown

◆ w