PAL labeling utilities. More...

#include <qgspallabeling.h>

Static Public Member Functions
static void	drawLabelCandidateRect (pal::LabelPosition lp, QPainter painter, const QgsMapToPixel xform, QList< QgsLabelCandidate > candidates=nullptr)

static bool	geometryRequiresPreparation (const QgsGeometry &geometry, QgsRenderContext &context, const QgsCoordinateTransform &ct, const QgsGeometry &clipGeometry=QgsGeometry(), bool mergeLines=false)
	Checks whether a geometry requires preparation before registration with PAL.

static QgsGeometry	prepareGeometry (const QgsGeometry &geometry, QgsRenderContext &context, const QgsCoordinateTransform &ct, const QgsGeometry &clipGeometry=QgsGeometry(), bool mergeLines=false)
	Prepares a geometry for registration with PAL.

static QStringList	splitToGraphemes (const QString &text)
	Splits a text string to a list of graphemes, which are the smallest allowable character divisions in the string.

static QStringList	splitToLines (const QString &text, const QString &wrapCharacter, int autoWrapLength=0, bool useMaxLineLengthWhenAutoWrapping=true)
	Splits a text string to a list of separate lines, using a specified wrap character (wrapCharacter).

static bool	staticWillUseLayer (const QgsMapLayer *layer)
	Called to find out whether a specified layer is used for labeling.

Friends
class	QgsDxfExport

class	QgsPalLayerSettings

class	QgsVectorLayerLabelProvider

Detailed Description

PAL labeling utilities.

Definition at line 1047 of file qgspallabeling.h.

Member Function Documentation

◆ drawLabelCandidateRect()

void QgsPalLabeling::drawLabelCandidateRect	(	pal::LabelPosition *	lp,
		QPainter *	painter,
		const QgsMapToPixel *	xform,
		QList< QgsLabelCandidate > *	candidates = `nullptr`
	)

static

Note: not available in Python bindings

Definition at line 4835 of file qgspallabeling.cpp.

◆ geometryRequiresPreparation()

bool QgsPalLabeling::geometryRequiresPreparation	(	const QgsGeometry &	geometry,
		QgsRenderContext &	context,
		const QgsCoordinateTransform &	ct,
		const QgsGeometry &	clipGeometry = `QgsGeometry()`,
		bool	mergeLines = `false`
	)

static

Checks whether a geometry requires preparation before registration with PAL.

Parameters

geometry	geometry to prepare
context	render context
ct	coordinate transform, or invalid transform if no transformation required
clipGeometry	geometry to clip features to, if applicable
mergeLines	`true` if touching lines from this layer will be merged and treated as single features during labeling

Returns: true if geometry requires preparation

Definition at line 4106 of file qgspallabeling.cpp.

◆ prepareGeometry()

QgsGeometry QgsPalLabeling::prepareGeometry	(	const QgsGeometry &	geometry,
		QgsRenderContext &	context,
		const QgsCoordinateTransform &	ct,
		const QgsGeometry &	clipGeometry = `QgsGeometry()`,
		bool	mergeLines = `false`
	)

static

Prepares a geometry for registration with PAL.

Handles reprojection, rotation, clipping, etc.

Parameters

geometry	geometry to prepare
context	render context
ct	coordinate transform, or invalid transform if no transformation required
clipGeometry	geometry to clip features to, if applicable
mergeLines	`true` if touching lines from this layer will be merged and treated as single features during labeling

Returns: prepared geometry

Definition at line 4183 of file qgspallabeling.cpp.

◆ splitToGraphemes()

QStringList QgsPalLabeling::splitToGraphemes ( const QString & text )

static

Splits a text string to a list of graphemes, which are the smallest allowable character divisions in the string.

This accounts for scripts were individual characters are not allowed to be split apart (e.g., Arabic and Indic based scripts)

Parameters

text	string to split

Returns: list of graphemes

Definition at line 4169 of file qgspallabeling.cpp.

◆ splitToLines()

QStringList QgsPalLabeling::splitToLines	(	const QString &	text,
		const QString &	wrapCharacter,
		int	autoWrapLength = `0`,
		bool	useMaxLineLengthWhenAutoWrapping = `true`
	)

static

Splits a text string to a list of separate lines, using a specified wrap character (wrapCharacter).

The text string will be split on either newline characters or the wrap character.

Since QGIS 3.4 the autoWrapLength argument can be used to specify an ideal length of line to automatically wrap text to (automatic wrapping is disabled if autoWrapLength is 0). This automatic wrapping is performed after processing wrapping using wrapCharacter. When auto wrapping is enabled, the useMaxLineLengthWhenAutoWrapping argument controls whether the lines should be wrapped to an ideal maximum of autoWrapLength characters, or if false then the lines are wrapped to an ideal minimum length of autoWrapLength characters.

Definition at line 4138 of file qgspallabeling.cpp.

◆ staticWillUseLayer()

bool QgsPalLabeling::staticWillUseLayer ( const QgsMapLayer * layer )

static

Called to find out whether a specified layer is used for labeling.

Definition at line 4071 of file qgspallabeling.cpp.

Friends And Related Symbol Documentation

◆ QgsDxfExport

friend class QgsDxfExport

friend

Definition at line 1129 of file qgspallabeling.h.

◆ QgsPalLayerSettings

friend class QgsPalLayerSettings

friend

Definition at line 1140 of file qgspallabeling.h.

◆ QgsVectorLayerLabelProvider

friend class QgsVectorLayerLabelProvider

friend

Definition at line 1128 of file qgspallabeling.h.

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

/build/qgis-3.41.0+git20241201+3c143d501a8+99sid/src/core/labeling/qgspallabeling.h
/build/qgis-3.41.0+git20241201+3c143d501a8+99sid/src/core/labeling/qgspallabeling.cpp

Static Public Member Functions

Friends

Detailed Description

Member Function Documentation

◆ drawLabelCandidateRect()

◆ geometryRequiresPreparation()

◆ prepareGeometry()

◆ splitToGraphemes()

◆ splitToLines()

◆ staticWillUseLayer()

Friends And Related Symbol Documentation

◆ QgsDxfExport

◆ QgsPalLayerSettings

◆ QgsVectorLayerLabelProvider