Base class for all diagram types. More...

#include <qgsdiagram.h>

Inheritance diagram for QgsDiagram:

[legend]

Public Member Functions
virtual	~QgsDiagram ()

void	clearCache ()

virtual QgsDiagram *	clone () const =0
	Returns an instance that is equivalent to this one.

virtual QString	diagramName () const =0
	Gets a descriptive name for this diagram type.

virtual QSizeF	diagramSize (const QgsAttributes &attributes, const QgsRenderContext &c, const QgsDiagramSettings &s)=0
	Returns the size in map units the diagram will use to render.

virtual QSizeF	diagramSize (const QgsFeature &feature, const QgsRenderContext &c, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &interpolationSettings)=0
	Returns the size in map units the diagram will use to render. Interpolate size.

QgsExpression *	getExpression (const QString &expression, const QgsExpressionContext &context)
	Returns a prepared expression for the specified context.

virtual double	legendSize (double value, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &interpolationSettings) const =0
	Returns the size of the legend item for the diagram corresponding to a specified value.

virtual void	renderDiagram (const QgsFeature &feature, QgsRenderContext &c, const QgsDiagramSettings &s, QPointF position)=0
	Draws the diagram at the given position (in pixel coordinates)

Protected Member Functions
	QgsDiagram ()=default

	QgsDiagram (const QgsDiagram &other)

QFont	scaledFont (const QgsDiagramSettings &s, const QgsRenderContext &c)
	Calculates a size to match the current settings and rendering context.

void	setPenWidth (QPen &pen, const QgsDiagramSettings &s, const QgsRenderContext &c)
	Changes the pen width to match the current settings and rendering context.

QSizeF	sizeForValue (double value, const QgsDiagramSettings &s, const QgsDiagramInterpolationSettings &interpolationSettings) const
	Returns the scaled size of a diagram for a value, respecting the specified diagram interpolation settings.

double	sizePainterUnits (double l, const QgsDiagramSettings &s, const QgsRenderContext &c)
	Calculates a length to match the current settings and rendering context.

QSizeF	sizePainterUnits (QSizeF size, const QgsDiagramSettings &s, const QgsRenderContext &c)
	Calculates a size to match the current settings and rendering context.

Detailed Description

Base class for all diagram types.

Definition at line 39 of file qgsdiagram.h.

Constructor & Destructor Documentation

◆ ~QgsDiagram()

virtual QgsDiagram::~QgsDiagram ( )

inlinevirtual

Definition at line 60 of file qgsdiagram.h.

◆ QgsDiagram() [1/2]

QgsDiagram::QgsDiagram ( )

protecteddefault

◆ QgsDiagram() [2/2]

QgsDiagram::QgsDiagram ( const QgsDiagram & other )

protected

Definition at line 21 of file qgsdiagram.cpp.

Member Function Documentation

◆ clearCache()

void QgsDiagram::clearCache ( )

Definition at line 27 of file qgsdiagram.cpp.

◆ clone()

virtual QgsDiagram * QgsDiagram::clone ( ) const

pure virtual

Returns an instance that is equivalent to this one.

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsStackedDiagram, and QgsTextDiagram.

◆ diagramName()

virtual QString QgsDiagram::diagramName ( ) const

pure virtual

Gets a descriptive name for this diagram type.

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsStackedDiagram, and QgsTextDiagram.

◆ diagramSize() [1/2]

virtual QSizeF QgsDiagram::diagramSize	(	const QgsAttributes &	attributes,
		const QgsRenderContext &	c,
		const QgsDiagramSettings &	s
	)

pure virtual

Returns the size in map units the diagram will use to render.

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsStackedDiagram, and QgsTextDiagram.

◆ diagramSize() [2/2]

virtual QSizeF QgsDiagram::diagramSize	(	const QgsFeature &	feature,
		const QgsRenderContext &	c,
		const QgsDiagramSettings &	s,
		const QgsDiagramInterpolationSettings &	interpolationSettings
	)

pure virtual

Returns the size in map units the diagram will use to render. Interpolate size.

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsTextDiagram, and QgsStackedDiagram.

◆ getExpression()

QgsExpression * QgsDiagram::getExpression	(	const QString &	expression,
		const QgsExpressionContext &	context
	)

Returns a prepared expression for the specified context.

Parameters

expression	expression string
context	expression context

Definition at line 38 of file qgsdiagram.cpp.

◆ legendSize()

virtual double QgsDiagram::legendSize	(	double	value,
		const QgsDiagramSettings &	s,
		const QgsDiagramInterpolationSettings &	interpolationSettings
	)		const

pure virtual

Returns the size of the legend item for the diagram corresponding to a specified value.

Parameters

value	value to return legend item size for
s	diagram settings
interpolationSettings	interpolation settings

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsTextDiagram, and QgsStackedDiagram.

◆ renderDiagram()

virtual void QgsDiagram::renderDiagram	(	const QgsFeature &	feature,
		QgsRenderContext &	c,
		const QgsDiagramSettings &	s,
		QPointF	position
	)

pure virtual

Draws the diagram at the given position (in pixel coordinates)

Implemented in QgsHistogramDiagram, QgsPieDiagram, QgsStackedBarDiagram, QgsStackedDiagram, and QgsTextDiagram.

◆ scaledFont()

QFont QgsDiagram::scaledFont	(	const QgsDiagramSettings &	s,
		const QgsRenderContext &	c
	)

protected

Calculates a size to match the current settings and rendering context.

Parameters

s	The settings that contain the font size and size type
c	The rendering specifying the proper scale units for pixel conversion

Returns: The properly scaled font for rendering

Definition at line 65 of file qgsdiagram.cpp.

◆ setPenWidth()

void QgsDiagram::setPenWidth	(	QPen &	pen,
		const QgsDiagramSettings &	s,
		const QgsRenderContext &	c
	)

protected

Changes the pen width to match the current settings and rendering context.

Parameters

pen	The pen to modify
s	The settings that specify the pen width
c	The rendering specifying the proper scale units for pixel conversion

Definition at line 49 of file qgsdiagram.cpp.

◆ sizeForValue()

QSizeF QgsDiagram::sizeForValue	(	double	value,
		const QgsDiagramSettings &	s,
		const QgsDiagramInterpolationSettings &	interpolationSettings
	)		const

protected

Returns the scaled size of a diagram for a value, respecting the specified diagram interpolation settings.

Parameters

value	value to calculate corresponding circular size for
s	diagram settings
interpolationSettings	interpolation settings

Definition at line 81 of file qgsdiagram.cpp.

◆ sizePainterUnits() [1/2]

double QgsDiagram::sizePainterUnits	(	double	l,
		const QgsDiagramSettings &	s,
		const QgsRenderContext &	c
	)

protected

Calculates a length to match the current settings and rendering context.

Parameters

l	The length to convert
s	The settings that specify the size type
c	The rendering specifying the proper scale units for pixel conversion

Returns: The converted length for rendering

Definition at line 60 of file qgsdiagram.cpp.

◆ sizePainterUnits() [2/2]

QSizeF QgsDiagram::sizePainterUnits	(	QSizeF	size,
		const QgsDiagramSettings &	s,
		const QgsRenderContext &	c
	)

protected

Calculates a size to match the current settings and rendering context.

Parameters

size	The size to convert
s	The settings that specify the size type
c	The rendering specifying the proper scale units for pixel conversion

Returns: The converted size for rendering

Definition at line 55 of file qgsdiagram.cpp.

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

/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/diagram/qgsdiagram.h
/build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/diagram/qgsdiagram.cpp

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ~QgsDiagram()

◆ QgsDiagram() [1/2]

◆ QgsDiagram() [2/2]

Member Function Documentation

◆ clearCache()

◆ clone()

◆ diagramName()

◆ diagramSize() [1/2]

◆ diagramSize() [2/2]

◆ getExpression()

◆ legendSize()

◆ renderDiagram()

◆ scaledFont()

◆ setPenWidth()

◆ sizeForValue()

◆ sizePainterUnits() [1/2]

◆ sizePainterUnits() [2/2]