Abstract base class for all rendered symbols. More...

#include <qgssymbol.h>

Inheritance diagram for QgsSymbol:

[legend]

Public Types
enum	PreviewFlag { FlagIncludeCrosshairsForMarkerSymbols = 1 << 0 }
	Flags for controlling how symbol preview images are generated. More...

enum	Property { PropertyOpacity }
	Data definable properties. More...

enum	RenderHint { DynamicRotation = 2 }
	Flags controlling behavior of symbols during rendering. More...

enum	ScaleMethod { ScaleArea , ScaleDiameter }
	Scale method. More...

enum	SymbolType { Marker , Line , Fill , Hybrid }
	Type of the symbol. More...

Public Member Functions
virtual	~QgsSymbol ()

bool	appendSymbolLayer (QgsSymbolLayer *layer)
	Appends a symbol layer at the end of the current symbol layer list. More...

QImage	asImage (QSize size, QgsRenderContext *customContext=nullptr)
	Returns an image of the symbol at the specified size. More...

QImage	bigSymbolPreviewImage (QgsExpressionContext *expressionContext=nullptr, QgsSymbol::PreviewFlags flags=QgsSymbol::FlagIncludeCrosshairsForMarkerSymbols)
	Returns a large (roughly 100x100 pixel) preview image for the symbol. More...

bool	canCauseArtifactsBetweenAdjacentTiles () const
	Returns `true` if the symbol rendering can cause visible artifacts across a single feature when the feature is rendered as a series of adjacent map tiles each containing a portion of the feature's geometry. More...

bool	changeSymbolLayer (int index, QgsSymbolLayer *layer)
	Deletes the current layer at the specified index and replaces it with layer. More...

bool	clipFeaturesToExtent () const
	Returns whether features drawn by the symbol will be clipped to the render context's extent. More...

virtual QgsSymbol *	clone () const =0
	Returns a deep copy of this symbol. More...

QColor	color () const
	Returns the symbol's color. More...

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

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

bool	deleteSymbolLayer (int index)
	Removes and deletes the symbol layer at the specified index. More...

void	drawPreviewIcon (QPainter painter, QSize size, QgsRenderContext customContext=nullptr, bool selected=false, const QgsExpressionContext expressionContext=nullptr, const QgsLegendPatchShape patchShape=nullptr)
	Draws an icon of the symbol that occupies an area given by size using the specified painter. More...

QString	dump () const
	Returns a string dump of the symbol's properties. More...

void	exportImage (const QString &path, const QString &format, QSize size)
	Export the symbol as an image format, to the specified path and with the given size. More...

bool	forceRHR () const
	Returns `true` if polygon features drawn by the symbol will be reoriented to follow the standard right-hand-rule orientation, in which the area that is bounded by the polygon is to the right of the boundary. More...

bool	hasDataDefinedProperties () const
	Returns whether the symbol utilizes any data defined properties. More...

bool	insertSymbolLayer (int index, QgsSymbolLayer *layer)
	Inserts a symbol layer to specified index. More...

Q_DECL_DEPRECATED const QgsVectorLayer *	layer () const

QgsMapUnitScale	mapUnitScale () const
	Returns the map unit scale for the symbol. More...

qreal	opacity () const
	Returns the opacity for the symbol. More...

QgsUnitTypes::RenderUnit	outputUnit () const
	Returns the units to use for sizes and widths within the symbol. More...

void	renderFeature (const QgsFeature &feature, QgsRenderContext &context, int layer=-1, bool selected=false, bool drawVertexMarker=false, int currentVertexMarkerType=0, double currentVertexMarkerSize=0.0) SIP_THROW(QgsCsException)
	Render a feature. More...

RenderHints	renderHints () const
	Returns the rendering hint flags for the symbol. More...

void	setClipFeaturesToExtent (bool clipFeaturesToExtent)
	Sets whether features drawn by the symbol should be clipped to the render context's extent. More...

void	setColor (const QColor &color)
	Sets the color for the symbol. More...

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

void	setDataDefinedProperty (Property key, const QgsProperty &property)
	Sets a data defined property for the symbol. More...

void	setForceRHR (bool force)
	Sets whether polygon features drawn by the symbol should be reoriented to follow the standard right-hand-rule orientation, in which the area that is bounded by the polygon is to the right of the boundary. More...

Q_DECL_DEPRECATED void	setLayer (const QgsVectorLayer *layer)

void	setMapUnitScale (const QgsMapUnitScale &scale)
	Sets the map unit scale for the symbol. More...

void	setOpacity (qreal opacity)
	Sets the opacity for the symbol. More...

void	setOutputUnit (QgsUnitTypes::RenderUnit unit)
	Sets the units to use for sizes and widths within the symbol. More...

void	setRenderHints (RenderHints hints)
	Sets rendering hint flags for the symbol. More...

void	startRender (QgsRenderContext &context, const QgsFields &fields=QgsFields())
	Begins the rendering process for the symbol. More...

void	stopRender (QgsRenderContext &context)
	Ends the rendering process. More...

QgsSymbolLayer *	symbolLayer (int layer)
	Returns the symbol layer at the specified index. More...

const QgsSymbolLayer *	symbolLayer (int layer) const
	Returns the symbol layer at the specified index, const variant. More...

int	symbolLayerCount () const
	Returns the total number of symbol layers contained in the symbol. More...

QgsSymbolLayerList	symbolLayers ()
	Returns the list of symbol layers contained in the symbol. More...

QgsSymbolRenderContext *	symbolRenderContext ()
	Returns the symbol render context. More...

QgsSymbolLayer *	takeSymbolLayer (int index)
	Removes a symbol layer from the list and returns a pointer to it. More...

void	toSld (QDomDocument &doc, QDomElement &element, QVariantMap props) const
	Converts the symbol to a SLD representation. More...

SymbolType	type () const
	Returns the symbol's type. More...

QSet< QString >	usedAttributes (const QgsRenderContext &context) const
	Returns a list of attributes required to render this feature. More...

bool	usesMapUnits () const
	Returns `true` if the symbol has any components which use map unit based sizes. More...

Static Public Member Functions
static QgsSymbol *	defaultSymbol (QgsWkbTypes::GeometryType geomType)
	Returns a new default symbol for the specified geometry type. More...

static const QgsPropertiesDefinition &	propertyDefinitions ()
	Returns the symbol property definitions. More...

Protected Member Functions
	QgsSymbol (SymbolType type, const QgsSymbolLayerList &layers)

QgsSymbolLayerList	cloneLayers () const
	Retrieve a cloned list of all layers that make up this symbol. More...

void	renderUsingLayer (QgsSymbolLayer *layer, QgsSymbolRenderContext &context)
	Renders a context using a particular symbol layer without passing in a geometry. More...

void	renderVertexMarker (QPointF pt, QgsRenderContext &context, int currentVertexMarkerType, double currentVertexMarkerSize)
	Render editing vertex marker at specified point. More...

Static Protected Member Functions
static QPolygonF	_getLineString (QgsRenderContext &context, const QgsCurve &curve, bool clipToExtent=true)
	Creates a line string in screen coordinates from a QgsCurve in map coordinates. More...

static QPointF	_getPoint (QgsRenderContext &context, const QgsPoint &point)
	Creates a point in screen coordinates from a QgsPoint in map coordinates. More...

static void	_getPolygon (QPolygonF &pts, QVector< QPolygonF > &holes, QgsRenderContext &context, const QgsPolygon &polygon, bool clipToExtent=true, bool correctRingOrientation=false)
	Creates a polygon in screen coordinates from a QgsPolygonXYin map coordinates. More...

static QPolygonF	_getPolygonRing (QgsRenderContext &context, const QgsCurve &curve, bool clipToExtent, bool isExteriorRing=false, bool correctRingOrientation=false)
	Creates a polygon ring in screen coordinates from a QgsCurve in map coordinates. More...

Protected Attributes
bool	mClipFeaturesToExtent = true

bool	mForceRHR = false

Q_DECL_DEPRECATED const QgsVectorLayer *	mLayer = nullptr

QgsSymbolLayerList	mLayers

qreal	mOpacity = 1.0
	Symbol opacity (in the range 0 - 1) More...

RenderHints	mRenderHints

SymbolType	mType

Friends
class	QgsFeatureRenderer

Detailed Description

Abstract base class for all rendered symbols.

Definition at line 64 of file qgssymbol.h.

Member Enumeration Documentation

◆ PreviewFlag

enum QgsSymbol::PreviewFlag

Flags for controlling how symbol preview images are generated.

Since: QGIS 3.16

Enumerator
FlagIncludeCrosshairsForMarkerSymbols	Include a crosshairs reference image in the background of marker symbol previews.

Definition at line 393 of file qgssymbol.h.

◆ Property

enum QgsSymbol::Property

Data definable properties.

Since: QGIS 3.18

Enumerator
PropertyOpacity	Opacity.

Definition at line 115 of file qgssymbol.h.

◆ RenderHint

enum QgsSymbol::RenderHint

Flags controlling behavior of symbols during rendering.

Enumerator
DynamicRotation	Rotation of symbol may be changed during rendering and symbol should not be cached.

Definition at line 105 of file qgssymbol.h.

◆ ScaleMethod

enum QgsSymbol::ScaleMethod

Scale method.

Enumerator
ScaleArea	Calculate scale by the area.
ScaleDiameter	Calculate scale by the diameter.

Definition at line 97 of file qgssymbol.h.

◆ SymbolType

enum QgsSymbol::SymbolType

Type of the symbol.

Enumerator
Marker	Marker symbol.
Line	Line symbol.
Fill	Fill symbol.
Hybrid	Hybrid symbol.

Definition at line 86 of file qgssymbol.h.

Constructor & Destructor Documentation

◆ ~QgsSymbol()

QgsSymbol::~QgsSymbol ( )

virtual

Definition at line 260 of file qgssymbol.cpp.

◆ QgsSymbol()

Q_NOWARN_DEPRECATED_PUSH QgsSymbol::QgsSymbol	(	SymbolType	type,
		const QgsSymbolLayerList &	layers
	)

protected

Definition at line 86 of file qgssymbol.cpp.

Member Function Documentation

◆ _getLineString()

Q_NOWARN_DEPRECATED_POP QPolygonF QgsSymbol::_getLineString	(	QgsRenderContext &	context,
		const QgsCurve &	curve,
		bool	clipToExtent = `true`
	)

staticprotected

Creates a line string in screen coordinates from a QgsCurve in map coordinates.

Definition at line 107 of file qgssymbol.cpp.

◆ _getPoint()

static QPointF QgsSymbol::_getPoint	(	QgsRenderContext &	context,
		const QgsPoint &	point
	)

inlinestaticprotected

Creates a point in screen coordinates from a QgsPoint in map coordinates.

Definition at line 632 of file qgssymbol.h.

◆ _getPolygon()

void QgsSymbol::_getPolygon	(	QPolygonF &	pts,
		QVector< QPolygonF > &	holes,
		QgsRenderContext &	context,
		const QgsPolygon &	polygon,
		bool	clipToExtent = `true`,
		bool	correctRingOrientation = `false`
	)

staticprotected

Creates a polygon in screen coordinates from a QgsPolygonXYin map coordinates.

If correctRingOrientation is true then the ring will be oriented to match standard ring orientation, e.g. clockwise for exterior rings and counter-clockwise for interior rings.

Definition at line 239 of file qgssymbol.cpp.

◆ _getPolygonRing()

QPolygonF QgsSymbol::_getPolygonRing	(	QgsRenderContext &	context,
		const QgsCurve &	curve,
		bool	clipToExtent,
		bool	isExteriorRing = `false`,
		bool	correctRingOrientation = `false`
	)

staticprotected

Creates a polygon ring in screen coordinates from a QgsCurve in map coordinates.

If correctRingOrientation is true then the ring will be oriented to match standard ring orientation, e.g. clockwise for exterior rings and counter-clockwise for interior rings.

Definition at line 168 of file qgssymbol.cpp.

◆ appendSymbolLayer()

bool QgsSymbol::appendSymbolLayer ( QgsSymbolLayer * layer )

Appends a symbol layer at the end of the current symbol layer list.

Ownership of layer is transferred to the symbol.

Returns: true if the layer was successfully added, false if the layer is not compatible with the symbol's type().

Definition at line 434 of file qgssymbol.cpp.

◆ asImage()

QImage QgsSymbol::asImage	(	QSize	size,
		QgsRenderContext *	customContext = `nullptr`
	)

Returns an image of the symbol at the specified size.

Optionally a custom render context may be given in order to ensure that the preview icon exactly matches the settings from that context.

See also: exportImage(); drawPreviewIcon()

Definition at line 655 of file qgssymbol.cpp.

◆ bigSymbolPreviewImage()

QImage QgsSymbol::bigSymbolPreviewImage	(	QgsExpressionContext *	expressionContext = `nullptr`,
		QgsSymbol::PreviewFlags	flags = `QgsSymbol::FlagIncludeCrosshairsForMarkerSymbols`
	)

Returns a large (roughly 100x100 pixel) preview image for the symbol.

Parameters

expressionContext	optional expression context, for evaluation of data defined symbol properties
flags	optional flags to control how preview image is generated

See also: asImage(); drawPreviewIcon()

Definition at line 669 of file qgssymbol.cpp.

◆ canCauseArtifactsBetweenAdjacentTiles()

bool QgsSymbol::canCauseArtifactsBetweenAdjacentTiles ( ) const

Returns true if the symbol rendering can cause visible artifacts across a single feature when the feature is rendered as a series of adjacent map tiles each containing a portion of the feature's geometry.

Internally this calls QgsSymbolLayer::canCauseArtifactsBetweenAdjacentTiles() for all symbol layers in the symbol and returns true if any of the layers returned TRUE.

Since: QGIS 3.18

Definition at line 824 of file qgssymbol.cpp.

◆ changeSymbolLayer()

bool QgsSymbol::changeSymbolLayer	(	int	index,
		QgsSymbolLayer *	layer
	)

Deletes the current layer at the specified index and replaces it with layer.

Ownership of layer is transferred to the symbol.

Returns false if layer is not compatible with the symbol's type(), or true if the layer was successfully replaced.

Definition at line 464 of file qgssymbol.cpp.

◆ clipFeaturesToExtent()

bool QgsSymbol::clipFeaturesToExtent ( ) const

inline

Returns whether features drawn by the symbol will be clipped to the render context's extent.

If this option is enabled then features which are partially outside the extent will be clipped. This speeds up rendering of the feature, but may have undesirable side effects for certain symbol types.

Returns: true if features will be clipped

See also: setClipFeaturesToExtent

Since: QGIS 2.9

Definition at line 522 of file qgssymbol.h.

◆ clone()

virtual QgsSymbol* QgsSymbol::clone ( ) const

pure virtual

Returns a deep copy of this symbol.

Ownership is transferred to the caller.

Implemented in QgsFillSymbol, QgsLineSymbol, and QgsMarkerSymbol.

◆ cloneLayers()

QgsSymbolLayerList QgsSymbol::cloneLayers ( ) const

protected

Retrieve a cloned list of all layers that make up this symbol.

Ownership is transferred to the caller.

Definition at line 754 of file qgssymbol.cpp.

◆ color()

QColor QgsSymbol::color ( ) const

Returns the symbol's color.

For multi-layer symbols, this method returns the color of the first unlocked symbol layer.

See also: setColor()

Definition at line 542 of file qgssymbol.cpp.

◆ dataDefinedProperties() [1/2]

QgsPropertyCollection& QgsSymbol::dataDefinedProperties ( )

inline

Returns a reference to the symbol's property collection, used for data defined overrides.

See also: setDataDefinedProperties(); Property

Since: QGIS 3.18

Definition at line 568 of file qgssymbol.h.

◆ dataDefinedProperties() [2/2]

const QgsPropertyCollection& QgsSymbol::dataDefinedProperties ( ) const

inline

Returns a reference to the symbol's property collection, used for data defined overrides.

See also: setDataDefinedProperties()

Since: QGIS 3.18

Definition at line 575 of file qgssymbol.h.

◆ defaultSymbol()

QgsSymbol * QgsSymbol::defaultSymbol ( QgsWkbTypes::GeometryType geomType )

static

Returns a new default symbol for the specified geometry type.

The caller takes ownership of the returned object.

Definition at line 346 of file qgssymbol.cpp.

◆ deleteSymbolLayer()

bool QgsSymbol::deleteSymbolLayer ( int index )

Removes and deletes the symbol layer at the specified index.

Definition at line 444 of file qgssymbol.cpp.

◆ drawPreviewIcon()

void QgsSymbol::drawPreviewIcon	(	QPainter *	painter,
		QSize	size,
		QgsRenderContext *	customContext = `nullptr`,
		bool	selected = `false`,
		const QgsExpressionContext *	expressionContext = `nullptr`,
		const QgsLegendPatchShape *	patchShape = `nullptr`
	)

Draws an icon of the symbol that occupies an area given by size using the specified painter.

Optionally a custom render context may be given in order to ensure that the preview icon exactly matches the settings from that context.

Parameters

painter	destination painter
size	size of the icon
customContext	the context in which the rendering happens
selected	set to `true` to render the symbol in a selected state
expressionContext	optional custom expression context
patchShape	optional patch shape to use for symbol preview. If not specified a default shape will be used instead.

See also: exportImage(); asImage()

Note: Parameter selected added in QGIS 3.10

Since: QGIS 2.6

Definition at line 553 of file qgssymbol.cpp.

◆ dump()

QString QgsSymbol::dump ( ) const

Returns a string dump of the symbol's properties.

Definition at line 715 of file qgssymbol.cpp.

◆ exportImage()

void QgsSymbol::exportImage	(	const QString &	path,
		const QString &	format,
		QSize	size
	)

Export the symbol as an image format, to the specified path and with the given size.

If format is "SVG" then an SVG file will be created, otherwise a raster image of the specified format will be created.

See also: asImage(); drawPreviewIcon()

Definition at line 635 of file qgssymbol.cpp.

◆ forceRHR()

bool QgsSymbol::forceRHR ( ) const

inline

Returns true if polygon features drawn by the symbol will be reoriented to follow the standard right-hand-rule orientation, in which the area that is bounded by the polygon is to the right of the boundary.

In particular, the exterior ring is oriented in a clockwise direction and the interior rings in a counter-clockwise direction.

See also: setForceRHR()

Since: QGIS 3.6

Definition at line 544 of file qgssymbol.h.

◆ hasDataDefinedProperties()

bool QgsSymbol::hasDataDefinedProperties ( ) const

Returns whether the symbol utilizes any data defined properties.

Since: QGIS 2.12

Definition at line 811 of file qgssymbol.cpp.

◆ insertSymbolLayer()

bool QgsSymbol::insertSymbolLayer	(	int	index,
		QgsSymbolLayer *	layer
	)

Inserts a symbol layer to specified index.

Ownership of layer is transferred to the symbol.

Parameters

index	The index at which the layer should be added
layer	The symbol layer to add

Returns: true if the layer is added, false if the index or the layer is bad

Definition at line 421 of file qgssymbol.cpp.

◆ layer()

const QgsVectorLayer * QgsSymbol::layer ( ) const

Deprecated:: Will be removed in QGIS 4.0

Definition at line 841 of file qgssymbol.cpp.

◆ mapUnitScale()

QgsMapUnitScale QgsSymbol::mapUnitScale ( ) const

Returns the map unit scale for the symbol.

If the symbol consists of multiple layers, the map unit scale is only returned if all layers have the same scale settings. If the settings differ, a default constructed map unit scale is returned.

See also: setMapUnitScale()

Definition at line 304 of file qgssymbol.cpp.

◆ opacity()

qreal QgsSymbol::opacity ( ) const

inline

Returns the opacity for the symbol.

Returns: opacity value between 0 (fully transparent) and 1 (fully opaque)

See also: setOpacity()

Definition at line 481 of file qgssymbol.h.

◆ outputUnit()

QgsUnitTypes::RenderUnit QgsSymbol::outputUnit ( ) const

Returns the units to use for sizes and widths within the symbol.

Individual symbol layer definitions will interpret this in different ways, e.g., a marker symbol may use it to specify the units for the marker size, while a line symbol may use it to specify the units for the line width.

Returns: output unit, or QgsUnitTypes::RenderUnknownUnit if the symbol contains mixed units

See also: setOutputUnit()

Definition at line 266 of file qgssymbol.cpp.

◆ propertyDefinitions()

const QgsPropertiesDefinition & QgsSymbol::propertyDefinitions ( )

static

Returns the symbol property definitions.

Since: QGIS 3.18

Definition at line 254 of file qgssymbol.cpp.

◆ renderFeature()

PRIVATE void QgsSymbol::renderFeature	(	const QgsFeature &	feature,
		QgsRenderContext &	context,
		int	layer = `-1`,
		bool	selected = `false`,
		bool	drawVertexMarker = `false`,
		int	currentVertexMarkerType = `0`,
		double	currentVertexMarkerSize = `0.0`
	)

Render a feature.

Before calling this the startRender() method should be called to initialize the rendering process. After rendering all features stopRender() must be called.

Definition at line 890 of file qgssymbol.cpp.

◆ renderHints()

RenderHints QgsSymbol::renderHints ( ) const

inline

Returns the rendering hint flags for the symbol.

See also: setRenderHints()

Definition at line 500 of file qgssymbol.h.

◆ renderUsingLayer()

void QgsSymbol::renderUsingLayer	(	QgsSymbolLayer *	layer,
		QgsSymbolRenderContext &	context
	)

protected

Renders a context using a particular symbol layer without passing in a geometry.

This is used as fallback, if the symbol being rendered is not compatible with the specified layer. In such a case, this method can be called and will call the layer's rendering method anyway but the geometry passed to the layer will be empty. This is required for layers that generate their own geometry from other information in the rendering context.

Definition at line 768 of file qgssymbol.cpp.

◆ renderVertexMarker()

void QgsSymbol::renderVertexMarker	(	QPointF	pt,
		QgsRenderContext &	context,
		int	currentVertexMarkerType,
		double	currentVertexMarkerSize
	)

protected

Render editing vertex marker at specified point.

Since: QGIS 2.16

Definition at line 1422 of file qgssymbol.cpp.

◆ setClipFeaturesToExtent()

void QgsSymbol::setClipFeaturesToExtent ( bool clipFeaturesToExtent )

inline

Sets whether features drawn by the symbol should be clipped to the render context's extent.

If this option is enabled then features which are partially outside the extent will be clipped. This speeds up rendering of the feature, but may have undesirable side effects for certain symbol types.

Parameters

clipFeaturesToExtent set to true to enable clipping (defaults to TRUE)

See also: clipFeaturesToExtent

Since: QGIS 2.9

Definition at line 511 of file qgssymbol.h.

◆ setColor()

void QgsSymbol::setColor ( const QColor & color )

Sets the color for the symbol.

Calling this method sets the color for each individual symbol layer contained within the symbol to color.

Locked symbol layers are skipped and are left unchanged.

See also: color()

Definition at line 532 of file qgssymbol.cpp.

◆ setDataDefinedProperties()

void QgsSymbol::setDataDefinedProperties ( const QgsPropertyCollection & collection )

inline

Sets the symbol's property collection, used for data defined overrides.

Parameters

collection property collection. Existing properties will be replaced.

See also: dataDefinedProperties()

Since: QGIS 3.18

Definition at line 583 of file qgssymbol.h.

◆ setDataDefinedProperty()

void QgsSymbol::setDataDefinedProperty	(	QgsSymbol::Property	key,
		const QgsProperty &	property
	)

Sets a data defined property for the symbol.

Any existing property with the same key will be overwritten.

See also: dataDefinedProperties(); Property

Since: QGIS 3.18

Definition at line 806 of file qgssymbol.cpp.

◆ setForceRHR()

void QgsSymbol::setForceRHR ( bool force )

inline

Sets whether polygon features drawn by the symbol should be reoriented to follow the standard right-hand-rule orientation, in which the area that is bounded by the polygon is to the right of the boundary.

In particular, the exterior ring is oriented in a clockwise direction and the interior rings in a counter-clockwise direction.

See also: forceRHR()

Since: QGIS 3.6

Definition at line 533 of file qgssymbol.h.

◆ setLayer()

void QgsSymbol::setLayer ( const QgsVectorLayer * layer )

Note: the layer will be nullptr after stopRender

Deprecated:: Will be removed in QGIS 4.0

Definition at line 834 of file qgssymbol.cpp.

◆ setMapUnitScale()

void QgsSymbol::setMapUnitScale ( const QgsMapUnitScale & scale )

Sets the map unit scale for the symbol.

Calling this method sets the scale for all symbol layers contained within the symbol.

See also: mapUnitScale()

Definition at line 337 of file qgssymbol.cpp.

◆ setOpacity()

void QgsSymbol::setOpacity ( qreal opacity )

inline

Sets the opacity for the symbol.

Parameters

opacity opacity value between 0 (fully transparent) and 1 (fully opaque)

See also: opacity()

Definition at line 488 of file qgssymbol.h.

◆ setOutputUnit()

void QgsSymbol::setOutputUnit ( QgsUnitTypes::RenderUnit unit )

Sets the units to use for sizes and widths within the symbol.

Individual symbol definitions will interpret this in different ways, e.g., a marker symbol may use it to specify the units for the marker size, while a line symbol may use it to specify the units for the line width.

Parameters

unit	output units

See also: outputUnit()

Definition at line 328 of file qgssymbol.cpp.

◆ setRenderHints()

void QgsSymbol::setRenderHints ( RenderHints hints )

inline

Sets rendering hint flags for the symbol.

See also: renderHints()

Definition at line 494 of file qgssymbol.h.

◆ startRender()

void QgsSymbol::startRender	(	QgsRenderContext &	context,
		const QgsFields &	fields = `QgsFields()`
	)

Begins the rendering process for the symbol.

This must be called before renderFeature(), and should be followed by a call to stopRender().

Parameters

context	render context which symbol will be drawn using
fields	fields for features to be rendered (usually the associated vector layer's fields). Required for correct calculation of data defined overrides.

See also: stopRender()

Definition at line 480 of file qgssymbol.cpp.

◆ stopRender()

void QgsSymbol::stopRender ( QgsRenderContext & context )

Ends the rendering process.

This should be called after rendering all desired features.

Parameters

context render context, must match the context specified when startRender() was called.

See also: startRender()

Definition at line 507 of file qgssymbol.cpp.

◆ symbolLayer() [1/2]

QgsSymbolLayer * QgsSymbol::symbolLayer ( int layer )

Returns the symbol layer at the specified index.

See also: symbolLayers; symbolLayerCount

Since: QGIS 2.7

Definition at line 411 of file qgssymbol.cpp.

◆ symbolLayer() [2/2]

const QgsSymbolLayer * QgsSymbol::symbolLayer ( int layer ) const

Returns the symbol layer at the specified index, const variant.

See also: symbolLayers; symbolLayerCount

Since: QGIS 3.12

Definition at line 416 of file qgssymbol.cpp.

◆ symbolLayerCount()

int QgsSymbol::symbolLayerCount ( ) const

inline

Returns the total number of symbol layers contained in the symbol.

Returns: count of symbol layers

See also: symbolLayers; symbolLayer

Since: QGIS 2.7

Definition at line 199 of file qgssymbol.h.

◆ symbolLayers()

QgsSymbolLayerList QgsSymbol::symbolLayers ( )

inline

Returns the list of symbol layers contained in the symbol.

Returns: symbol layers list

See also: symbolLayer; symbolLayerCount

Since: QGIS 2.7

Definition at line 149 of file qgssymbol.h.

◆ symbolRenderContext()

QgsSymbolRenderContext * QgsSymbol::symbolRenderContext ( )

Returns the symbol render context.

Only valid between startRender and stopRender calls.

Returns: The symbol render context

Definition at line 1417 of file qgssymbol.cpp.

◆ takeSymbolLayer()

QgsSymbolLayer * QgsSymbol::takeSymbolLayer ( int index )

Removes a symbol layer from the list and returns a pointer to it.

Ownership of the layer is handed to the caller.

Parameters

index The index of the layer to remove

Returns: A pointer to the removed layer

Definition at line 455 of file qgssymbol.cpp.

◆ toSld()

void QgsSymbol::toSld	(	QDomDocument &	doc,
		QDomElement &	element,
		QVariantMap	props
	)		const

Converts the symbol to a SLD representation.

Definition at line 741 of file qgssymbol.cpp.

◆ type()

SymbolType QgsSymbol::type ( ) const

inline

Returns the symbol's type.

Definition at line 138 of file qgssymbol.h.

◆ usedAttributes()

QSet< QString > QgsSymbol::usedAttributes ( const QgsRenderContext & context ) const

Returns a list of attributes required to render this feature.

This should include any attributes required by the symbology including the ones required by expressions.

Definition at line 789 of file qgssymbol.cpp.

◆ usesMapUnits()

bool QgsSymbol::usesMapUnits ( ) const

Returns true if the symbol has any components which use map unit based sizes.

Since: QGIS 3.18

Definition at line 287 of file qgssymbol.cpp.

Friends And Related Function Documentation

◆ QgsFeatureRenderer

friend class QgsFeatureRenderer

friend

Definition at line 79 of file qgssymbol.h.

Member Data Documentation

◆ mClipFeaturesToExtent

bool QgsSymbol::mClipFeaturesToExtent = true

protected

Definition at line 703 of file qgssymbol.h.

◆ mForceRHR

bool QgsSymbol::mForceRHR = false

protected

Definition at line 704 of file qgssymbol.h.

◆ mLayer

Q_DECL_DEPRECATED const QgsVectorLayer* QgsSymbol::mLayer = nullptr

protected

Definition at line 706 of file qgssymbol.h.

◆ mLayers

QgsSymbolLayerList QgsSymbol::mLayers

protected

Definition at line 697 of file qgssymbol.h.

◆ mOpacity

qreal QgsSymbol::mOpacity = 1.0

protected

Symbol opacity (in the range 0 - 1)

Definition at line 700 of file qgssymbol.h.

◆ mRenderHints

RenderHints QgsSymbol::mRenderHints

protected

Definition at line 702 of file qgssymbol.h.

◆ mType

SymbolType QgsSymbol::mType

protected

Definition at line 696 of file qgssymbol.h.

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

/build/qgis-3.18.1+99unstable/src/core/symbology/qgssymbol.h
/build/qgis-3.18.1+99unstable/src/core/symbology/qgssymbol.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ PreviewFlag

◆ Property

◆ RenderHint

◆ ScaleMethod

◆ SymbolType

Constructor & Destructor Documentation

◆ ~QgsSymbol()

◆ QgsSymbol()

Member Function Documentation

◆ _getLineString()

◆ _getPoint()

◆ _getPolygon()

◆ _getPolygonRing()

◆ appendSymbolLayer()

◆ asImage()

◆ bigSymbolPreviewImage()

◆ canCauseArtifactsBetweenAdjacentTiles()

◆ changeSymbolLayer()

◆ clipFeaturesToExtent()

◆ clone()

◆ cloneLayers()

◆ color()

◆ dataDefinedProperties() [1/2]

◆ dataDefinedProperties() [2/2]

◆ defaultSymbol()

◆ deleteSymbolLayer()

◆ drawPreviewIcon()

◆ dump()

◆ exportImage()

◆ forceRHR()

◆ hasDataDefinedProperties()

◆ insertSymbolLayer()

◆ layer()

◆ mapUnitScale()

◆ opacity()

◆ outputUnit()

◆ propertyDefinitions()

◆ renderFeature()

◆ renderHints()

◆ renderUsingLayer()

◆ renderVertexMarker()

◆ setClipFeaturesToExtent()

◆ setColor()

◆ setDataDefinedProperties()

◆ setDataDefinedProperty()

◆ setForceRHR()

◆ setLayer()

◆ setMapUnitScale()

◆ setOpacity()

◆ setOutputUnit()

◆ setRenderHints()

◆ startRender()

◆ stopRender()

◆ symbolLayer() [1/2]

◆ symbolLayer() [2/2]

◆ symbolLayerCount()

◆ symbolLayers()

◆ symbolRenderContext()

◆ takeSymbolLayer()

◆ toSld()

◆ type()

◆ usedAttributes()

◆ usesMapUnits()

Friends And Related Function Documentation

◆ QgsFeatureRenderer

Member Data Documentation

◆ mClipFeaturesToExtent

◆ mForceRHR

◆ mLayer

◆ mLayers

◆ mOpacity