A renderer that automatically clusters points with the same geographic position. More...

#include <qgspointclusterrenderer.h>

Inheritance diagram for QgsPointClusterRenderer:

Public Member Functions
	QgsPointClusterRenderer ()

QgsPointClusterRenderer *	clone () const override
	Create a deep copy of this renderer. More...

QgsMarkerSymbol *	clusterSymbol ()
	Returns the symbol used for rendering clustered groups (but not ownership of the symbol). More...

QDomElement	save (QDomDocument &doc, const QgsReadWriteContext &context) override
	store renderer info to XML element More...

void	setClusterSymbol (QgsMarkerSymbol *symbol)
	Sets the symbol for rendering clustered groups. More...

void	startRender (QgsRenderContext &context, const QgsFields &fields) override
	Must be called when a new render cycle is started. More...

void	stopRender (QgsRenderContext &context) override
	Must be called when a render cycle has finished, to allow the renderer to clean up. More...

QSet< QString >	usedAttributes (const QgsRenderContext &context) const override
	Return a list of attributes required by this renderer. More...

Public Member Functions inherited from QgsPointDistanceRenderer
	QgsPointDistanceRenderer (const QString &rendererName, const QString &labelAttributeName=QString())
	Constructor for QgsPointDistanceRenderer. More...

QgsFeatureRenderer::Capabilities	capabilities () override
	Returns details about internals of this renderer. More...

void	checkLegendSymbolItem (const QString &key, bool state) override
	item in symbology was checked More...

const QgsFeatureRenderer *	embeddedRenderer () const override
	Returns the current embedded renderer (subrenderer) for this feature renderer. More...

QString	filter (const QgsFields &fields=QgsFields()) override
	If a renderer does not require all the features this method may be overridden and return an expression used as where clause. More...

QString	labelAttributeName () const
	Returns the attribute name used for labeling points, or an empty string if no labeling will be done by the renderer. More...

QColor	labelColor () const
	Returns the color used for for labeling points. More...

QFont	labelFont () const
	Returns the font used for labeling points. More...

QSet< QString >	legendKeysForFeature (QgsFeature &feature, QgsRenderContext &context) override
	Return legend keys matching a specified feature. More...

bool	legendSymbolItemChecked (const QString &key) override
	items of symbology items in legend is checked More...

QgsLegendSymbolList	legendSymbolItems () const override
	Returns a list of symbology items for the legend. More...

bool	legendSymbolItemsCheckable () const override
	items of symbology items in legend should be checkable More...

double	minimumLabelScale () const
	Returns the minimum map scale (i.e. More...

QgsSymbol *	originalSymbolForFeature (QgsFeature &feat, QgsRenderContext &context) override
	Return symbol for feature. More...

QgsSymbolList	originalSymbolsForFeature (QgsFeature &feat, QgsRenderContext &context) override
	Equivalent of originalSymbolsForFeature() call extended to support renderers that may use more symbols per feature - similar to symbolsForFeature() More...

bool	renderFeature (QgsFeature &feature, QgsRenderContext &context, int layer=-1, bool selected=false, bool drawVertexMarker=false) override
	Render a feature using this renderer in the given context. More...

void	setEmbeddedRenderer (QgsFeatureRenderer *r) override
	Sets an embedded renderer (subrenderer) for this feature renderer. More...

void	setLabelAttributeName (const QString &name)
	Sets the attribute name for labeling points. More...

void	setLabelColor (const QColor &color)
	Sets the color to use for for labeling points. More...

void	setLabelFont (const QFont &font)
	Sets the font used for labeling points. More...

void	setLegendSymbolItem (const QString &key, QgsSymbol *symbol) override
	Sets the symbol to be used for a legend symbol item. More...

void	setMinimumLabelScale (double scale)
	Sets the minimum map scale (i.e. More...

void	setTolerance (double distance)
	Sets the tolerance distance for grouping points. More...

void	setToleranceMapUnitScale (const QgsMapUnitScale &scale)
	Sets the map unit scale object for the distance tolerance. More...

void	setToleranceUnit (QgsUnitTypes::RenderUnit unit)
	Sets the units for the tolerance distance. More...

void	startRender (QgsRenderContext &context, const QgsFields &fields) override
	Must be called when a new render cycle is started. More...

void	stopRender (QgsRenderContext &context) override
	Must be called when a render cycle has finished, to allow the renderer to clean up. More...

QgsSymbol *	symbolForFeature (QgsFeature &feature, QgsRenderContext &context) override
	To be overridden. More...

QgsSymbolList	symbols (QgsRenderContext &context) override
	Returns list of symbols used by the renderer. More...

QgsSymbolList	symbolsForFeature (QgsFeature &feat, QgsRenderContext &context) override
	Returns list of symbols used for rendering the feature. More...

double	tolerance () const
	Returns the tolerance distance for grouping points. More...

const QgsMapUnitScale &	toleranceMapUnitScale () const
	Returns the map unit scale object for the distance tolerance. More...

QgsUnitTypes::RenderUnit	toleranceUnit () const
	Returns the units for the tolerance distance. More...

void	toSld (QDomDocument &doc, QDomElement &element, const QgsStringMap &props=QgsStringMap()) const override
	used from subclasses to create SLD Rule elements following SLD v1.1 specs More...

QSet< QString >	usedAttributes (const QgsRenderContext &context) const override
	Return a list of attributes required by this renderer. More...

bool	willRenderFeature (QgsFeature &feat, QgsRenderContext &context) override
	Returns whether the renderer will render a feature or not. More...

Public Member Functions inherited from QgsFeatureRenderer
virtual	~QgsFeatureRenderer ()

virtual QString	dump () const
	Returns debug information about this renderer. More...

virtual bool	filterNeedsGeometry () const
	Returns true if this renderer requires the geometry to apply the filter. More...

bool	forceRasterRender () const
	Returns whether the renderer must render as a raster. More...

virtual QString	legendClassificationAttribute () const
	If supported by the renderer, return classification attribute for the use in legend. More...

virtual void	modifyRequestExtent (QgsRectangle &extent, QgsRenderContext &context)
	Allows for a renderer to modify the extent of a feature request prior to rendering. More...

QgsFeatureRequest::OrderBy	orderBy () const
	Get the order in which features shall be processed by this renderer. More...

bool	orderByEnabled () const
	Returns whether custom ordering will be applied before features are processed by this renderer. More...

QgsPaintEffect *	paintEffect () const
	Returns the current paint effect for the renderer. More...

void	setForceRasterRender (bool forceRaster)
	Sets whether the renderer should be rendered to a raster destination. More...

void	setOrderBy (const QgsFeatureRequest::OrderBy &orderBy)
	Define the order in which features shall be processed by this renderer. More...

void	setOrderByEnabled (bool enabled)
	Sets whether custom ordering should be applied before features are processed by this renderer. More...

void	setPaintEffect (QgsPaintEffect *effect)
	Sets the current paint effect for the renderer. More...

void	setUsingSymbolLevels (bool usingSymbolLevels)

void	setVertexMarkerAppearance (int type, int size)
	set type and size of editing vertex markers for subsequent rendering More...

QString	type () const

bool	usingSymbolLevels () const

virtual QDomElement	writeSld (QDomDocument &doc, const QString &styleName, const QgsStringMap &props=QgsStringMap()) const
	create the SLD UserStyle element following the SLD v1.1 specs with the given name More...

Static Public Member Functions
static QgsPointClusterRenderer *	convertFromRenderer (const QgsFeatureRenderer *renderer)
	Creates a QgsPointClusterRenderer from an existing renderer. More...

static QgsFeatureRenderer *	create (QDomElement &symbologyElem, const QgsReadWriteContext &context)
	Creates a renderer from XML element. More...

Static Public Member Functions inherited from QgsFeatureRenderer
static QgsFeatureRenderer *	defaultRenderer (QgsWkbTypes::GeometryType geomType)
	return a new renderer - used by default in vector layers More...

static QgsFeatureRenderer *	load (QDomElement &symbologyElem, const QgsReadWriteContext &context)
	create a renderer from XML element More...

static QgsFeatureRenderer *	loadSld (const QDomNode &node, QgsWkbTypes::GeometryType geomType, QString &errorMessage)
	Create a new renderer according to the information contained in the UserStyle element of a SLD style document. More...

Additional Inherited Members
Public Types inherited from QgsPointDistanceRenderer
typedef QList< QgsPointDistanceRenderer::GroupedFeature >	ClusteredGroup
	A group of clustered points (ie features within the distance tolerance). More...

Public Types inherited from QgsFeatureRenderer
enum	Capability { SymbolLevels = 1, MoreSymbolsPerFeature = 1 << 2, Filter = 1 << 3, ScaleDependent = 1 << 4 }
	Used to specify details about a renderer. More...

Protected Member Functions inherited from QgsPointDistanceRenderer
void	drawLabels (QPointF centerPoint, QgsSymbolRenderContext &context, const QList< QPointF > &labelShifts, const ClusteredGroup &group)
	Renders the labels for a group. More...

Protected Member Functions inherited from QgsFeatureRenderer
	QgsFeatureRenderer (const QString &type)

void	copyRendererData (QgsFeatureRenderer *destRenderer) const
	Clones generic renderer data to another renderer. More...

void	renderFeatureWithSymbol (QgsFeature &feature, QgsSymbol *symbol, QgsRenderContext &context, int layer, bool selected, bool drawVertexMarker)

void	renderVertexMarker (QPointF pt, QgsRenderContext &context)
	render editing vertex marker at specified point More...

void	renderVertexMarkerPolygon (QPolygonF &pts, QList< QPolygonF > *rings, QgsRenderContext &context)
	render editing vertex marker for a polygon More...

void	renderVertexMarkerPolyline (QPolygonF &pts, QgsRenderContext &context)
	render editing vertex marker for a polyline More...

Static Protected Member Functions inherited from QgsFeatureRenderer
static QPointF	_getPoint (QgsRenderContext &context, const QgsPoint &point)
	Creates a point in screen coordinates from a wkb string in map coordinates. More...

static void	convertSymbolRotation (QgsSymbol *symbol, const QString &field)

static void	convertSymbolSizeScale (QgsSymbol *symbol, QgsSymbol::ScaleMethod method, const QString &field)

Protected Attributes inherited from QgsPointDistanceRenderer
QList< ClusteredGroup >	mClusteredGroups
	Groups of features that are considered clustered together. More...

bool	mDrawLabels
	Whether labels should be drawn for points. This is set internally from startRender() depending on scale denominator. More...

QMap< QgsFeatureId, int >	mGroupIndex
	Mapping of feature ID to the feature's group index. More...

QMap< QgsFeatureId, QgsPointXY >	mGroupLocations
	Mapping of feature ID to approximate group location. More...

QString	mLabelAttributeName
	Attribute name for labeling. An empty string indicates that no labels should be rendered. More...

QColor	mLabelColor
	Label text color. More...

QFont	mLabelFont
	Label font. More...

int	mLabelIndex
	Label attribute index (or -1 if none). This index is not stored, it is requested in the startRender() method. More...

double	mMinLabelScale = 0
	Maximum scale denominator for label display. A zero value indicates no scale limitation. More...

std::unique_ptr< QgsFeatureRenderer >	mRenderer
	Embedded base renderer. This can be used for rendering individual, isolated points. More...

QgsSpatialIndex *	mSpatialIndex = nullptr
	Spatial index for fast lookup of nearby points. More...

double	mTolerance
	Distance tolerance. Points that are closer together than this distance are considered clustered. More...

QgsMapUnitScale	mToleranceMapUnitScale
	Map unit scale for distance tolerance. More...

QgsUnitTypes::RenderUnit	mToleranceUnit
	Unit for distance tolerance. More...

Protected Attributes inherited from QgsFeatureRenderer
int	mCurrentVertexMarkerSize
	The current size of editing marker. More...

int	mCurrentVertexMarkerType
	The current type of editing marker. More...

bool	mForceRaster

QgsFeatureRequest::OrderBy	mOrderBy

bool	mOrderByEnabled

QgsPaintEffect *	mPaintEffect = nullptr

QString	mType

bool	mUsingSymbolLevels

Detailed Description

A renderer that automatically clusters points with the same geographic position.

Since: QGIS 3.0

Definition at line 31 of file qgspointclusterrenderer.h.

Constructor & Destructor Documentation

◆ QgsPointClusterRenderer()

QgsPointClusterRenderer::QgsPointClusterRenderer ( )

Definition at line 27 of file qgspointclusterrenderer.cpp.

Member Function Documentation

◆ clone()

QgsPointClusterRenderer * QgsPointClusterRenderer::clone ( ) const

overridevirtual

Create a deep copy of this renderer.

Should be implemented by all subclasses and generate a proper subclass.

Returns: A copy of this renderer

Implements QgsFeatureRenderer.

Definition at line 43 of file qgspointclusterrenderer.cpp.

◆ clusterSymbol()

QgsMarkerSymbol * QgsPointClusterRenderer::clusterSymbol ( )

Returns the symbol used for rendering clustered groups (but not ownership of the symbol).

See also: setClusterSymbol()

Definition at line 119 of file qgspointclusterrenderer.cpp.

◆ convertFromRenderer()

QgsPointClusterRenderer * QgsPointClusterRenderer::convertFromRenderer ( const QgsFeatureRenderer * renderer )

static

Creates a QgsPointClusterRenderer from an existing renderer.

Returns: a new renderer if the conversion was possible, otherwise nullptr.

Definition at line 171 of file qgspointclusterrenderer.cpp.

◆ create()

QgsFeatureRenderer * QgsPointClusterRenderer::create	(	QDomElement &	symbologyElem,
		const QgsReadWriteContext &	context
	)

static

Creates a renderer from XML element.

Definition at line 96 of file qgspointclusterrenderer.cpp.

◆ save()

QDomElement QgsPointClusterRenderer::save	(	QDomDocument &	doc,
		const QgsReadWriteContext &	context
	)

overridevirtual

store renderer info to XML element

Reimplemented from QgsFeatureRenderer.

Definition at line 124 of file qgspointclusterrenderer.cpp.

◆ setClusterSymbol()

void QgsPointClusterRenderer::setClusterSymbol ( QgsMarkerSymbol * symbol )

Sets the symbol for rendering clustered groups.

Parameters

symbol new cluster symbol. Ownership is transferred to the renderer.

See also: clusterSymbol()

Definition at line 166 of file qgspointclusterrenderer.cpp.

◆ startRender()

void QgsPointClusterRenderer::startRender	(	QgsRenderContext &	context,
		const QgsFields &	fields
	)

overridevirtual

Must be called when a new render cycle is started.

A call to startRender() must always be followed by a corresponding call to stopRender() after all features have been rendered.

Parameters

context	Additional information passed to the renderer about the job which will be rendered
fields	The fields available for rendering

See also: stopRender()

Warning: This method is not thread safe. Before calling startRender() in a non-main thread, the renderer should instead be cloned and startRender()/stopRender() called on the clone.

Reimplemented from QgsFeatureRenderer.

Definition at line 78 of file qgspointclusterrenderer.cpp.

◆ stopRender()

void QgsPointClusterRenderer::stopRender ( QgsRenderContext & context )

overridevirtual

Must be called when a render cycle has finished, to allow the renderer to clean up.

Calls to stopRender() must always be preceded by a call to startRender().

Warning: This method is not thread safe. Before calling startRender() in a non-main thread, the renderer should instead be cloned and startRender()/stopRender() called on the clone.