Draws curved lines as callouts. More...

#include <qgscallout.h>

Inheritance diagram for QgsCurvedLineCallout:

[legend]

Public Types
enum	Orientation { Automatic , Clockwise , CounterClockwise }
	Curve orientation. More...

Public Types inherited from QgsCallout
enum	AnchorPoint { PoleOfInaccessibility = 0 , PointOnExterior , PointOnSurface , Centroid }
	Feature's anchor point position. More...

enum	DrawOrder { OrderBelowAllLabels , OrderBelowIndividualLabels }
	Options for draw order (stacking) of callouts. More...

enum	LabelAnchorPoint { LabelPointOnExterior , LabelCentroid , LabelTopLeft , LabelTopMiddle , LabelTopRight , LabelMiddleLeft , LabelMiddleRight , LabelBottomLeft , LabelBottomMiddle , LabelBottomRight }
	Label's anchor point position. More...

enum class	Property : int { MinimumCalloutLength , OffsetFromAnchor , OffsetFromLabel , DrawCalloutToAllParts , AnchorPointPosition , LabelAnchorPointPosition , OriginX , OriginY , DestinationX , DestinationY , Curvature , Orientation , Margins , WedgeWidth , CornerRadius , BlendMode }
	Data definable properties. More...

Public Member Functions
	QgsCurvedLineCallout ()

	QgsCurvedLineCallout (const QgsCurvedLineCallout &other)

QgsCurvedLineCallout *	clone () const override
	Duplicates a callout by creating a deep copy of the callout.

double	curvature () const
	Returns the callout line's curvature.

QgsCurvedLineCallout &	operator= (const QgsCurvedLineCallout &)=delete

Orientation	orientation () const
	Returns the callout line's curve orientation.

QVariantMap	properties (const QgsReadWriteContext &context) const override
	Returns the properties describing the callout encoded in a string format.

void	setCurvature (double curvature)
	Sets the callout line's curvature.

void	setOrientation (Orientation orientation)
	Sets the callout line's curve orientation.

QString	type () const override
	Returns a unique string representing the callout type.

Public Member Functions inherited from QgsSimpleLineCallout
	QgsSimpleLineCallout ()

	QgsSimpleLineCallout (const QgsSimpleLineCallout &other)

	~QgsSimpleLineCallout () override

QgsSimpleLineCallout *	clone () const override
	Duplicates a callout by creating a deep copy of the callout.

bool	drawCalloutToAllParts () const
	Returns `true` if callout lines should be drawn to all feature parts.

QgsLineSymbol *	lineSymbol ()
	Returns the line symbol used to render the callout line.

double	minimumLength () const
	Returns the minimum length of callout lines.

const QgsMapUnitScale &	minimumLengthMapUnitScale () const
	Returns the map unit scale for the minimum callout length.

Qgis::RenderUnit	minimumLengthUnit () const
	Returns the units for the minimum length of callout lines.

double	offsetFromAnchor () const
	Returns the offset distance from the anchor point at which to start the line.

const QgsMapUnitScale &	offsetFromAnchorMapUnitScale () const
	Returns the map unit scale for the offset from anchor.

Qgis::RenderUnit	offsetFromAnchorUnit () const
	Returns the units for the offset from anchor point.

double	offsetFromLabel () const
	Returns the offset distance from label area at which to end the line.

const QgsMapUnitScale &	offsetFromLabelMapUnitScale () const
	Returns the map unit scale for the minimum callout length.

Qgis::RenderUnit	offsetFromLabelUnit () const
	Returns the units for the offset from label area.

QgsSimpleLineCallout &	operator= (const QgsSimpleLineCallout &)=delete

QVariantMap	properties (const QgsReadWriteContext &context) const override
	Returns the properties describing the callout encoded in a string format.

void	readProperties (const QVariantMap &props, const QgsReadWriteContext &context) override
	Reads a string map of an callout's properties and restores the callout to the state described by the properties map.

QSet< QString >	referencedFields (const QgsRenderContext &context) const override
	Returns the set of attributes referenced by the callout.

void	setDrawCalloutToAllParts (bool drawToAllParts)
	Sets whether callout lines should be drawn to all feature parts.

void	setLineSymbol (QgsLineSymbol *symbol)
	Sets the line symbol used to render the callout line.

void	setMinimumLength (double length)
	Sets the minimum length of callout lines.

void	setMinimumLengthMapUnitScale (const QgsMapUnitScale &scale)
	Sets the map unit scale for the minimum callout length.

void	setMinimumLengthUnit (Qgis::RenderUnit unit)
	Sets the unit for the minimum length of callout lines.

void	setOffsetFromAnchor (double distance)
	Sets the offset distance from the anchor point at which to start the line.

void	setOffsetFromAnchorMapUnitScale (const QgsMapUnitScale &scale)
	Sets the map unit scale for the offset from anchor.

void	setOffsetFromAnchorUnit (Qgis::RenderUnit unit)
	Sets the unit for the offset from anchor distance.

void	setOffsetFromLabel (double distance)
	Sets the offset distance from label area at which to end the line.

void	setOffsetFromLabelMapUnitScale (const QgsMapUnitScale &scale)
	Sets the map unit scale for the offset from label area.

void	setOffsetFromLabelUnit (Qgis::RenderUnit unit)
	Sets the unit for the offset from label area distance.

void	startRender (QgsRenderContext &context) override
	Prepares the callout for rendering on the specified render context.

void	stopRender (QgsRenderContext &context) override
	Finalises the callout after a set of rendering operations on the specified render context.

QString	type () const override
	Returns a unique string representing the callout type.

Public Member Functions inherited from QgsCallout
	QgsCallout ()
	Constructor for QgsCallout.

virtual	~QgsCallout ()=default

AnchorPoint	anchorPoint () const
	Returns the feature's anchor point position.

QPainter::CompositionMode	blendMode () const
	Returns the blending mode used for drawing callouts.

bool	containsAdvancedEffects () const
	Returns `true` if the callout requires advanced effects such as blend modes, which require output in raster formats to be fully respected.

QgsPropertyCollection &	dataDefinedProperties ()
	Returns a reference to the callout's property collection, used for data defined overrides.

const QgsPropertyCollection &	dataDefinedProperties () const
	Returns a reference to the callout's property collection, used for data defined overrides.

virtual DrawOrder	drawOrder () const
	Returns the desired drawing order (stacking) to use while rendering this callout.

bool	enabled () const
	Returns `true` if the the callout is enabled.

LabelAnchorPoint	labelAnchorPoint () const
	Returns the label's anchor point position.

void	render (QgsRenderContext &context, const QRectF &rect, const double angle, const QgsGeometry &anchor, QgsCalloutContext &calloutContext)
	Renders the callout onto the specified render context.

virtual void	restoreProperties (const QDomElement &element, const QgsReadWriteContext &context)
	Restores the callout's properties from a DOM element.

virtual bool	saveProperties (QDomDocument &doc, QDomElement &element, const QgsReadWriteContext &context) const
	Saves the current state of the callout to a DOM element.

void	setAnchorPoint (AnchorPoint anchor)
	Sets the feature's anchor point position.

void	setBlendMode (QPainter::CompositionMode mode)
	Sets the blending mode used for drawing callouts.

void	setDataDefinedProperties (const QgsPropertyCollection &collection)
	Sets the callout's property collection, used for data defined overrides.

void	setEnabled (bool enabled)
	Sets whether the callout is enabled.

void	setLabelAnchorPoint (LabelAnchorPoint anchor)
	Sets the label's anchor point position.

Static Public Member Functions
static QgsCallout *	create (const QVariantMap &properties=QVariantMap(), const QgsReadWriteContext &context=QgsReadWriteContext())
	Creates a new QgsCurvedLineCallout, using the settings serialized in the properties map (corresponding to the output from QgsCurvedLineCallout::properties() ).

Static Public Member Functions inherited from QgsSimpleLineCallout
static QgsCallout *	create (const QVariantMap &properties=QVariantMap(), const QgsReadWriteContext &context=QgsReadWriteContext())
	Creates a new QgsSimpleLineCallout, using the settings serialized in the properties map (corresponding to the output from QgsSimpleLineCallout::properties() ).

Static Public Member Functions inherited from QgsCallout
static QgsCallout::AnchorPoint	decodeAnchorPoint (const QString &name, bool *ok=nullptr)
	Attempts to decode a string representation of an anchor point name to the corresponding anchor point.

static QgsCallout::LabelAnchorPoint	decodeLabelAnchorPoint (const QString &name, bool *ok=nullptr)
	Attempts to decode a string representation of a label anchor point name to the corresponding anchor point.

static QString	encodeAnchorPoint (AnchorPoint anchor)
	Encodes an anchor point to its string representation.

static QString	encodeLabelAnchorPoint (LabelAnchorPoint anchor)
	Encodes a label anchor point to its string representation.

static QgsPropertiesDefinition	propertyDefinitions ()
	Returns the definitions for data defined properties available for use in callouts.

Protected Member Functions
QgsCurve *	createCalloutLine (const QgsPoint &start, const QgsPoint &end, QgsRenderContext &context, const QRectF &bodyBoundingBox, const double angle, const QgsGeometry &anchor, QgsCalloutContext &calloutContext) const override
	Creates a callout line between start and end in the desired style.

Protected Member Functions inherited from QgsSimpleLineCallout
void	draw (QgsRenderContext &context, const QRectF &bodyBoundingBox, const double angle, const QgsGeometry &anchor, QgsCallout::QgsCalloutContext &calloutContext) override
	Performs the actual rendering of the callout implementation onto the specified render context.

Protected Member Functions inherited from QgsCallout
QgsGeometry	calloutLabelPoint (const QRectF &bodyBoundingBox, double angle, LabelAnchorPoint anchor, QgsRenderContext &context, const QgsCalloutContext &calloutContext, bool &pinned) const
	Returns the anchor point geometry for a label with the given bounding box and anchor point mode.

QgsGeometry	calloutLineToPart (const QgsGeometry &labelGeometry, const QgsAbstractGeometry *partGeometry, QgsRenderContext &context, const QgsCalloutContext &calloutContext, bool &pinned) const
	Calculates the direct line from a label geometry to an anchor geometry part, respecting the various callout settings which influence how the callout end should be placed in the anchor geometry.

Q_DECL_DEPRECATED QgsGeometry	labelAnchorGeometry (const QRectF &bodyBoundingBox, const double angle, LabelAnchorPoint anchor) const
	Returns the anchor point geometry for a label with the given bounding box and anchor point mode.

Detailed Description

Draws curved lines as callouts.

Since: QGIS 3.20

Definition at line 784 of file qgscallout.h.

Member Enumeration Documentation

◆ Orientation

enum QgsCurvedLineCallout::Orientation

Curve orientation.

Enumerator
Automatic	Automatically choose most cartographically pleasing orientation based on label and callout arrangement.
Clockwise	Curve lines in a clockwise direction.
CounterClockwise	Curve lines in a counter-clockwise direction.

Definition at line 791 of file qgscallout.h.

Constructor & Destructor Documentation

◆ QgsCurvedLineCallout() [1/2]

QgsCurvedLineCallout::QgsCurvedLineCallout ( )

Definition at line 789 of file qgscallout.cpp.

◆ QgsCurvedLineCallout() [2/2]

QgsCurvedLineCallout::QgsCurvedLineCallout ( const QgsCurvedLineCallout & other )

Definition at line 793 of file qgscallout.cpp.

Member Function Documentation

◆ clone()

QgsCurvedLineCallout * QgsCurvedLineCallout::clone ( ) const

overridevirtual

Duplicates a callout by creating a deep copy of the callout.

Caller takes ownership of the returned object.

Implements QgsCallout.

Definition at line 817 of file qgscallout.cpp.

◆ create()

QgsCallout * QgsCurvedLineCallout::create	(	const QVariantMap &	properties = `QVariantMap()`,
		const QgsReadWriteContext &	context = `QgsReadWriteContext()`
	)

static

Creates a new QgsCurvedLineCallout, using the settings serialized in the properties map (corresponding to the output from QgsCurvedLineCallout::properties() ).

Definition at line 801 of file qgscallout.cpp.

◆ createCalloutLine()

QgsCurve * QgsCurvedLineCallout::createCalloutLine	(	const QgsPoint &	start,
		const QgsPoint &	end,
		QgsRenderContext &	context,
		const QRectF &	bodyBoundingBox,
		const double	angle,
		const QgsGeometry &	anchor,
		QgsCallout::QgsCalloutContext &	calloutContext
	)		const

overrideprotectedvirtual

Creates a callout line between start and end in the desired style.

The base class method returns a straight line.

Since: QGIS 3.20

Reimplemented from QgsSimpleLineCallout.

Definition at line 830 of file qgscallout.cpp.

◆ curvature()

double QgsCurvedLineCallout::curvature ( ) const

Returns the callout line's curvature.

The curvature is a percentage value (with typical ranges between 0.0 and 1.0), representing the overall curvature of the line.

See also: setCurvature()

Definition at line 1016 of file qgscallout.cpp.

◆ operator=()

QgsCurvedLineCallout & QgsCurvedLineCallout::operator= ( const QgsCurvedLineCallout & )

delete

◆ orientation()

QgsCurvedLineCallout::Orientation QgsCurvedLineCallout::orientation ( ) const

Returns the callout line's curve orientation.

See also: setOrientation()

Definition at line 1006 of file qgscallout.cpp.

◆ properties()

QVariantMap QgsCurvedLineCallout::properties ( const QgsReadWriteContext & context ) const

overridevirtual

Returns the properties describing the callout encoded in a string format.

Subclasses must ensure that they include the base class' properties() in their returned value.

See also: readProperties(); saveProperties()

Reimplemented from QgsCallout.

Definition at line 822 of file qgscallout.cpp.

◆ setCurvature()

void QgsCurvedLineCallout::setCurvature ( double curvature )

Sets the callout line's curvature.

The curvature is a percentage value (with typical ranges between 0.0 and 1.0), representing the overall curvature of the line.

See also: curvature()

Definition at line 1021 of file qgscallout.cpp.

◆ setOrientation()

void QgsCurvedLineCallout::setOrientation ( Orientation orientation )

Sets the callout line's curve orientation.

See also: orientation()

Definition at line 1011 of file qgscallout.cpp.

◆ type()

QString QgsCurvedLineCallout::type ( ) const

overridevirtual

Returns a unique string representing the callout type.

Implements QgsCallout.

Definition at line 812 of file qgscallout.cpp.

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

/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/callouts/qgscallout.h
/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/callouts/qgscallout.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

◆ Orientation

Constructor & Destructor Documentation

◆ QgsCurvedLineCallout() [1/2]

◆ QgsCurvedLineCallout() [2/2]

Member Function Documentation

◆ clone()

◆ create()

◆ createCalloutLine()

◆ curvature()

◆ operator=()

◆ orientation()

◆ properties()

◆ setCurvature()

◆ setOrientation()

◆ type()