A set of features which influence the labeling process. More...

#include <layer.h>

Public Member Functions
	Layer (QgsAbstractLabelProvider provider, const QString &name, Qgis::LabelPlacement arrangement, double defaultPriority, bool active, bool toLabel, Pal pal)
	Create a new layer.

virtual	~Layer ()

bool	active () const
	Returns whether the layer is currently active.

Qgis::LabelPlacement	arrangement () const
	Returns the layer's arrangement policy.

bool	centroidInside () const
	Returns whether labels placed at the centroid of features within the layer are forced to be placed inside the feature's geometry.

void	chopFeaturesAtRepeatDistance ()
	Chop layer features at the repeat distance.

int	connectedFeatureId (QgsFeatureId featureId) const
	Returns the connected feature ID for a label feature ID, which is unique for all features which have been joined as a result of joinConnectedFeatures()

int	featureCount () const
	Returns the number of features in layer.

bool	isCurved () const
	Returns `true` if the layer has curved labels.

void	joinConnectedFeatures ()
	Join connected features with the same label text.

bool	labelLayer () const
	Returns whether the layer will be labeled or not.

std::size_t	maximumLineLabelCandidates () const
	Returns the maximum number of line label candidates to generate for features in this layer.

std::size_t	maximumPointLabelCandidates () const
	Returns the maximum number of point label candidates to generate for features in this layer.

std::size_t	maximumPolygonLabelCandidates () const
	Returns the maximum number of polygon label candidates to generate for features in this layer.

bool	mergeConnectedLines () const
	Returns whether connected lines will be merged before labeling.

QString	name () const
	Returns the layer's name.

QgsLabelObstacleSettings::ObstacleType	obstacleType () const
	Returns the obstacle type, which controls how features within the layer act as obstacles for labels.

double	priority () const
	Returns the layer's priority, between 0 and 1.

QgsAbstractLabelProvider *	provider () const
	Returns pointer to the associated provider.

bool	registerFeature (QgsLabelFeature *label)
	Register a feature in the layer.

void	setActive (bool active)
	Sets whether the layer is currently active.

void	setArrangement (Qgis::LabelPlacement arrangement)
	Sets the layer's arrangement policy.

void	setCentroidInside (bool forceInside)
	Sets whether labels placed at the centroid of features within the layer are forced to be placed inside the feature's geometry.

void	setLabelLayer (bool toLabel)
	Sets whether the layer will be labeled.

void	setMergeConnectedLines (bool merge)
	Sets whether connected lines should be merged before labeling.

void	setObstacleType (QgsLabelObstacleSettings::ObstacleType obstacleType)
	Sets the obstacle type, which controls how features within the layer act as obstacles for labels.

void	setPriority (double priority)
	Sets the layer's priority.

void	setUpsidedownLabels (Qgis::UpsideDownLabelHandling ud)
	Sets how upside down labels will be handled within the layer.

Qgis::UpsideDownLabelHandling	upsidedownLabels () const
	Returns how upside down labels are handled within the layer.

Protected Member Functions
void	addFeaturePart (std::unique_ptr< FeaturePart > fpart, const QString &labelText=QString())
	Add newly created feature part into r tree and to the list.

void	addObstaclePart (FeaturePart *fpart)
	Add newly created obstacle part into r tree and to the list.

Protected Attributes
bool	mActive

Qgis::LabelPlacement	mArrangement
	Optional flags used for some placement methods.

bool	mCentroidInside = false

QHash< QgsFeatureId, int >	mConnectedFeaturesIds

QHash< QString, QVector< FeaturePart * > >	mConnectedHashtable

double	mDefaultPriority

std::deque< std::unique_ptr< FeaturePart > >	mFeatureParts
	List of feature parts.

std::vector< geos::unique_ptr >	mGeosObstacleGeometries

QHash< QgsFeatureId, QgsLabelFeature * >	mHashtable
	Lookup table of label features (owned by the label feature provider that created them)

bool	mLabelLayer

bool	mMergeLines = false

QMutex	mMutex

QString	mName

QList< FeaturePart * >	mObstacleParts
	List of obstacle parts.

QgsLabelObstacleSettings::ObstacleType	mObstacleType = QgsLabelObstacleSettings::ObstacleType::PolygonBoundary

Pal *	mPal = nullptr

QgsAbstractLabelProvider *	mProvider

Qgis::UpsideDownLabelHandling	mUpsidedownLabels = Qgis::UpsideDownLabelHandling::FlipUpsideDownLabels

Friends
class	FeaturePart

class	LabelPosition

class	Pal

class	Problem

Detailed Description

A set of features which influence the labeling process.

Note: not available in Python bindings

Definition at line 61 of file layer.h.

Constructor & Destructor Documentation

◆ Layer()

Layer::Layer	(	QgsAbstractLabelProvider *	provider,
		const QString &	name,
		Qgis::LabelPlacement	arrangement,
		double	defaultPriority,
		bool	active,
		bool	toLabel,
		Pal *	pal
	)

Create a new layer.

Parameters

provider	Associated provider
name	Name of the layer (for stats, debugging - does not need to be unique)
arrangement	Arrangement mode : how to place candidates
defaultPriority	layer's priority (0 is the best, 1 the worst)
active	is the layer is active (currently displayed)
toLabel	the layer will be labeled whether toLablel is `true`
pal	pointer to the pal object

Definition at line 44 of file layer.cpp.

◆ ~Layer()

Layer::~Layer ( )

virtual

Definition at line 60 of file layer.cpp.

Member Function Documentation

◆ active()

bool pal::Layer::active ( ) const

inline

Returns whether the layer is currently active.

See also: setActive

Definition at line 197 of file layer.h.

◆ addFeaturePart()

void Layer::addFeaturePart	(	std::unique_ptr< FeaturePart >	fpart,
		const QString &	labelText = `QString()`
	)

protected

Add newly created feature part into r tree and to the list.

Definition at line 262 of file layer.cpp.

◆ addObstaclePart()

void Layer::addObstaclePart ( FeaturePart * fpart )

protected

Add newly created obstacle part into r tree and to the list.

Definition at line 274 of file layer.cpp.

◆ arrangement()

Qgis::LabelPlacement pal::Layer::arrangement ( ) const

inline

Returns the layer's arrangement policy.

See also: setArrangement

Definition at line 167 of file layer.h.

◆ centroidInside()

bool pal::Layer::centroidInside ( ) const

inline

Returns whether labels placed at the centroid of features within the layer are forced to be placed inside the feature's geometry.

See also: setCentroidInside

Definition at line 284 of file layer.h.

◆ chopFeaturesAtRepeatDistance()

void Layer::chopFeaturesAtRepeatDistance ( )

Chop layer features at the repeat distance.

Definition at line 365 of file layer.cpp.

◆ connectedFeatureId()

int Layer::connectedFeatureId ( QgsFeatureId featureId ) const

Returns the connected feature ID for a label feature ID, which is unique for all features which have been joined as a result of joinConnectedFeatures()

Returns: connected feature ID, or -1 if feature was not joined

Definition at line 360 of file layer.cpp.

◆ featureCount()

int pal::Layer::featureCount ( ) const

inline

Returns the number of features in layer.

Definition at line 90 of file layer.h.

◆ isCurved()

bool pal::Layer::isCurved ( ) const

inline

Returns true if the layer has curved labels.

Definition at line 172 of file layer.h.

◆ joinConnectedFeatures()

void Layer::joinConnectedFeatures ( )

Join connected features with the same label text.

Definition at line 297 of file layer.cpp.

◆ labelLayer()

bool pal::Layer::labelLayer ( ) const

inline

Returns whether the layer will be labeled or not.

See also: setLabelLayer

Definition at line 212 of file layer.h.

◆ maximumLineLabelCandidates()

std::size_t pal::Layer::maximumLineLabelCandidates ( ) const

inline

Returns the maximum number of line label candidates to generate for features in this layer.

Definition at line 117 of file layer.h.

◆ maximumPointLabelCandidates()

std::size_t pal::Layer::maximumPointLabelCandidates ( ) const

inline

Returns the maximum number of point label candidates to generate for features in this layer.

Definition at line 96 of file layer.h.

◆ maximumPolygonLabelCandidates()

std::size_t pal::Layer::maximumPolygonLabelCandidates ( ) const

inline

Returns the maximum number of polygon label candidates to generate for features in this layer.

Definition at line 138 of file layer.h.

◆ mergeConnectedLines()

bool pal::Layer::mergeConnectedLines ( ) const

inline

Returns whether connected lines will be merged before labeling.

See also: setMergeConnectedLines

Definition at line 255 of file layer.h.

◆ name()

QString pal::Layer::name ( ) const

inline

Returns the layer's name.

Definition at line 161 of file layer.h.

◆ obstacleType()

QgsLabelObstacleSettings::ObstacleType pal::Layer::obstacleType ( ) const

inline

Returns the obstacle type, which controls how features within the layer act as obstacles for labels.

See also: setObstacleType

Definition at line 219 of file layer.h.

◆ priority()

double pal::Layer::priority ( ) const

inline

Returns the layer's priority, between 0 and 1.

0 corresponds to highest priority, 1 to lowest priority.

See also: setPriority

Definition at line 242 of file layer.h.

◆ provider()

QgsAbstractLabelProvider * pal::Layer::provider ( ) const

inline

Returns pointer to the associated provider.

Definition at line 156 of file layer.h.

◆ registerFeature()

bool Layer::registerFeature ( QgsLabelFeature * label )

Register a feature in the layer.

Does not take ownership of the label feature (it is owned by its provider).

Exceptions

PalException::FeatureExists

Returns: true on success (i.e. valid geometry)

Definition at line 79 of file layer.cpp.

◆ setActive()

void pal::Layer::setActive ( bool active )

inline

Sets whether the layer is currently active.

Active means "is currently displayed or used as obstacles". When a layer is deactivated then feature of this layer will not be used for either labeling or as obstacles.

Parameters

active set to true to make the layer active, or false to deactivate the layer

See also: active

Definition at line 191 of file layer.h.

◆ setArrangement()

void pal::Layer::setArrangement ( Qgis::LabelPlacement arrangement )

inline

Sets the layer's arrangement policy.

Parameters

arrangement arrangement policy

See also: arrangement

Definition at line 179 of file layer.h.

◆ setCentroidInside()

void pal::Layer::setCentroidInside ( bool forceInside )

inline

Sets whether labels placed at the centroid of features within the layer are forced to be placed inside the feature's geometry.

Parameters

forceInside set to true to force centroid labels to be within the feature. If set to false then the centroid may fall outside the feature.

See also: centroidInside

Definition at line 277 of file layer.h.

◆ setLabelLayer()

void pal::Layer::setLabelLayer ( bool toLabel )

inline

Sets whether the layer will be labeled.

Note: Layers are labelled if and only if labelLayer and active are true

Parameters

toLabel set to false disable labeling this layer

See also: labelLayer; setActive

Definition at line 206 of file layer.h.

◆ setMergeConnectedLines()

void pal::Layer::setMergeConnectedLines ( bool merge )

inline

Sets whether connected lines should be merged before labeling.

Parameters

merge set to true to merge connected lines

See also: mergeConnectedLines

Definition at line 249 of file layer.h.

◆ setObstacleType()

void pal::Layer::setObstacleType ( QgsLabelObstacleSettings::ObstacleType obstacleType )

inline

Sets the obstacle type, which controls how features within the layer act as obstacles for labels.

Parameters

obstacleType new obstacle type

See also: obstacleType

Definition at line 227 of file layer.h.

◆ setPriority()

void Layer::setPriority ( double priority )

Sets the layer's priority.

Parameters

priority layer priority, between 0 and 1. 0 corresponds to highest priority, 1 to lowest priority.

See also: priority

Definition at line 69 of file layer.cpp.

◆ setUpsidedownLabels()

void pal::Layer::setUpsidedownLabels ( Qgis::UpsideDownLabelHandling ud )

inline

Sets how upside down labels will be handled within the layer.

Parameters

ud	upside down label handling mode

See also: upsidedownLabels

Definition at line 262 of file layer.h.

◆ upsidedownLabels()

Qgis::UpsideDownLabelHandling pal::Layer::upsidedownLabels ( ) const

inline

Returns how upside down labels are handled within the layer.

See also: setUpsidedownLabels

Definition at line 268 of file layer.h.

Friends And Related Symbol Documentation

◆ FeaturePart

friend class FeaturePart

friend

Definition at line 64 of file layer.h.

◆ LabelPosition

friend class LabelPosition

friend

Definition at line 68 of file layer.h.

◆ Pal

friend class Pal

friend

Definition at line 63 of file layer.h.

◆ Problem

friend class Problem

friend

Definition at line 66 of file layer.h.

Member Data Documentation

◆ mActive

bool pal::Layer::mActive

protected

Definition at line 327 of file layer.h.

◆ mArrangement

Qgis::LabelPlacement pal::Layer::mArrangement

protected

Optional flags used for some placement methods.

Definition at line 332 of file layer.h.

◆ mCentroidInside

bool pal::Layer::mCentroidInside = false

protected

Definition at line 329 of file layer.h.

◆ mConnectedFeaturesIds

QHash< QgsFeatureId, int > pal::Layer::mConnectedFeaturesIds

protected

Definition at line 342 of file layer.h.

◆ mConnectedHashtable

QHash< QString, QVector<FeaturePart *> > pal::Layer::mConnectedHashtable

protected

Definition at line 341 of file layer.h.

◆ mDefaultPriority

double pal::Layer::mDefaultPriority

protected

Definition at line 324 of file layer.h.

◆ mFeatureParts

std::deque< std::unique_ptr< FeaturePart > > pal::Layer::mFeatureParts

protected

List of feature parts.

Definition at line 315 of file layer.h.

◆ mGeosObstacleGeometries

std::vector< geos::unique_ptr > pal::Layer::mGeosObstacleGeometries

protected

Definition at line 320 of file layer.h.

◆ mHashtable

QHash< QgsFeatureId, QgsLabelFeature *> pal::Layer::mHashtable

protected

Lookup table of label features (owned by the label feature provider that created them)

Definition at line 339 of file layer.h.

◆ mLabelLayer

bool pal::Layer::mLabelLayer

protected

Definition at line 328 of file layer.h.

◆ mMergeLines

bool pal::Layer::mMergeLines = false

protected

Definition at line 334 of file layer.h.

◆ mMutex

QMutex pal::Layer::mMutex

protected

Definition at line 344 of file layer.h.

◆ mName

QString pal::Layer::mName

protected

Definition at line 312 of file layer.h.

◆ mObstacleParts

QList<FeaturePart *> pal::Layer::mObstacleParts

protected

List of obstacle parts.

Definition at line 318 of file layer.h.

◆ mObstacleType

QgsLabelObstacleSettings::ObstacleType pal::Layer::mObstacleType = QgsLabelObstacleSettings::ObstacleType::PolygonBoundary

protected

Definition at line 326 of file layer.h.

◆ mPal

Pal* pal::Layer::mPal = nullptr

protected

Definition at line 322 of file layer.h.

◆ mProvider

QgsAbstractLabelProvider* pal::Layer::mProvider

protected

Definition at line 311 of file layer.h.

◆ mUpsidedownLabels

Qgis::UpsideDownLabelHandling pal::Layer::mUpsidedownLabels = Qgis::UpsideDownLabelHandling::FlipUpsideDownLabels

protected

Definition at line 336 of file layer.h.

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

/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/pal/layer.h
/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/pal/layer.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ Layer()

◆ ~Layer()

Member Function Documentation

◆ active()

◆ addFeaturePart()

◆ addObstaclePart()

◆ arrangement()

◆ centroidInside()

◆ chopFeaturesAtRepeatDistance()

◆ connectedFeatureId()

◆ featureCount()

◆ isCurved()

◆ joinConnectedFeatures()

◆ labelLayer()

◆ maximumLineLabelCandidates()

◆ maximumPointLabelCandidates()

◆ maximumPolygonLabelCandidates()

◆ mergeConnectedLines()

◆ name()

◆ obstacleType()

◆ priority()

◆ provider()

◆ registerFeature()

◆ setActive()

◆ setArrangement()

◆ setCentroidInside()

◆ setLabelLayer()

◆ setMergeConnectedLines()

◆ setObstacleType()

◆ setPriority()

◆ setUpsidedownLabels()

◆ upsidedownLabels()

Friends And Related Symbol Documentation

◆ FeaturePart

◆ LabelPosition

◆ Pal

◆ Problem

Member Data Documentation

◆ mActive

◆ mArrangement

◆ mCentroidInside

◆ mConnectedFeaturesIds

◆ mConnectedHashtable

◆ mDefaultPriority

◆ mFeatureParts

◆ mGeosObstacleGeometries

◆ mHashtable

◆ mLabelLayer

◆ mMergeLines

◆ mMutex

◆ mName

◆ mObstacleParts

◆ mObstacleType

◆ mPal

◆ mProvider

◆ mUpsidedownLabels