QgsInvertedPolygonRenderer is a polygon-only feature renderer used to display features inverted, where the exterior is turned to an interior and where the exterior theoretically spans the entire plane, allowing to mask the surroundings of some features. More...

#include <qgsinvertedpolygonrenderer.h>

Inheritance diagram for QgsInvertedPolygonRenderer:

[legend]

Public Member Functions
	QgsInvertedPolygonRenderer (const QgsInvertedPolygonRenderer &)=delete
	Direct copies are forbidden. Use clone() instead.

	QgsInvertedPolygonRenderer (QgsFeatureRenderer *embeddedRenderer=nullptr)
	Constructor.

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

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

QgsInvertedPolygonRenderer &	operator= (const QgsInvertedPolygonRenderer &)=delete
	Direct copies are forbidden. Use clone() instead.

bool	preprocessingEnabled () const

QDomElement	save (QDomDocument &doc, const QgsReadWriteContext &context) override
	Stores renderer properties to an XML element.

void	setPreprocessingEnabled (bool enabled)

Public Member Functions inherited from QgsMergedFeatureRenderer
	QgsMergedFeatureRenderer (const QgsMergedFeatureRenderer &)=delete
	Direct copies are forbidden. Use clone() instead.

	QgsMergedFeatureRenderer (QgsFeatureRenderer *embeddedRenderer)
	Constructor for QgsMergedFeatureRenderer.

bool	accept (QgsStyleEntityVisitorInterface *visitor) const override
	Accepts the specified symbology visitor, causing it to visit all symbols associated with the renderer.

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

void	checkLegendSymbolItem (const QString &key, bool state=true) override
	Sets whether the legend symbology item with the specified ley should be checked.

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

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

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

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

Qgis::FeatureRendererFlags	flags () const override
	Returns flags associated with the renderer.

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

QString	legendKeyToExpression (const QString &key, QgsVectorLayer *layer, bool &ok) const override
	Attempts to convert the specified legend rule key to a QGIS expression matching the features displayed using that key.

bool	legendSymbolItemChecked (const QString &key) override
	Returns `true` if the legend symbology item with the specified key is checked.

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

bool	legendSymbolItemsCheckable () const override
	Returns `true` if symbology items in legend are checkable.

QgsMergedFeatureRenderer &	operator= (const QgsMergedFeatureRenderer &)=delete
	Direct copies are forbidden. Use clone() instead.

QgsSymbol *	originalSymbolForFeature (const QgsFeature &feature, QgsRenderContext &context) const override
	Returns symbol for feature.

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

bool	renderFeature (const QgsFeature &feature, QgsRenderContext &context, int layer=-1, bool selected=false, bool drawVertexMarker=false) override
	Renders a given feature.

QDomElement	save (QDomDocument &doc, const QgsReadWriteContext &context) override
	Stores renderer properties to an XML element.

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

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

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

void	stopRender (QgsRenderContext &context) override
	The actual rendering will take place here.

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

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

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

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

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

Public Member Functions inherited from QgsFeatureRenderer
virtual	~QgsFeatureRenderer ()

virtual bool	canSkipRender ()
	Returns `true` if the renderer can be entirely skipped, i.e.

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

virtual QList< QgsLayerTreeModelLegendNode * >	createLegendNodes (QgsLayerTreeLayer *nodeLayer) const
	Returns a list of legend nodes to be used for the legend for the renderer.

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

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

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

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

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

QSet< QString >	legendKeys () const
	Returns the set of all legend keys used by the renderer.

double	maximumExtentBuffer (QgsRenderContext &context) const
	Returns the maximum extent buffer found in this renderer's symbols.

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

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

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

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

double	referenceScale () const
	Returns the symbology reference scale.

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

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

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

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

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

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

void	setReferenceScale (double scale)
	Sets the symbology reference scale.

void	setUsingSymbolLevels (bool usingSymbolLevels)

void	setVertexMarkerAppearance (Qgis::VertexMarkerType type, double size)
	Sets type and size of editing vertex markers for subsequent rendering.

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

QString	type () const

virtual bool	usesEmbeddedSymbols () const
	Returns `true` if the renderer uses embedded symbols for features.

bool	usingSymbolLevels () const

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

Static Public Member Functions
static QgsInvertedPolygonRenderer *	convertFromRenderer (const QgsFeatureRenderer *renderer)
	Creates a QgsInvertedPolygonRenderer by a conversion from an existing renderer.

static QgsFeatureRenderer *	create (QDomElement &element, const QgsReadWriteContext &context)
	Creates a renderer out of an XML, for loading.

Static Public Member Functions inherited from QgsMergedFeatureRenderer
static QgsMergedFeatureRenderer *	convertFromRenderer (const QgsFeatureRenderer *renderer)
	Creates a QgsMergedFeatureRenderer by a conversion from an existing renderer.

static QgsFeatureRenderer *	create (QDomElement &element, const QgsReadWriteContext &context)
	Creates a renderer out of an XML, for loading.

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

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

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

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

Additional Inherited Members
Public Types inherited from QgsFeatureRenderer
typedef QFlags< Capability >	Capabilities

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

enum class	Property : int { HeatmapRadius , HeatmapMaximum }
	Data definable properties for renderers. More...

Protected Types inherited from QgsMergedFeatureRenderer
enum	GeometryOperation { Merge , InvertOnly , MergeAndInvert }
	Operations to apply to collected geometries prior to rendering. More...

Protected Member Functions inherited from QgsMergedFeatureRenderer
	QgsMergedFeatureRenderer (const QString &type, QgsFeatureRenderer *embeddedRenderer)
	Constructor for QgsMergedFeatureRenderer.

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

void	renderFeatureWithSymbol (const QgsFeature &feature, QgsSymbol *symbol, QgsRenderContext &context, int layer, bool selected, bool drawVertexMarker)
	Render the feature with the symbol using context.

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

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

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

void	saveRendererData (QDomDocument &doc, QDomElement &element, const QgsReadWriteContext &context)
	Saves generic renderer data into the specified element.

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.

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

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

Protected Attributes inherited from QgsMergedFeatureRenderer
GeometryOperation	mOperation = Merge
	Operation to apply to collected geometries.

std::unique_ptr< QgsFeatureRenderer >	mSubRenderer
	Embedded renderer.

Protected Attributes inherited from QgsFeatureRenderer
double	mCurrentVertexMarkerSize = 2
	The current size of editing marker.

Qgis::VertexMarkerType	mCurrentVertexMarkerType = Qgis::VertexMarkerType::Cross
	The current type of editing marker.

bool	mForceRaster = false

QgsFeatureRequest::OrderBy	mOrderBy

bool	mOrderByEnabled = false

QgsPaintEffect *	mPaintEffect = nullptr

double	mReferenceScale = -1.0

QString	mType

bool	mUsingSymbolLevels = false

Detailed Description

QgsInvertedPolygonRenderer is a polygon-only feature renderer used to display features inverted, where the exterior is turned to an interior and where the exterior theoretically spans the entire plane, allowing to mask the surroundings of some features.

It is designed on top of another feature renderer, which is called "embedded" Most of the methods are then only proxies to the embedded renderer.

Features are collected to form one "inverted" polygon during renderFeature() and rendered on stopRender().

Definition at line 41 of file qgsinvertedpolygonrenderer.h.

Constructor & Destructor Documentation

◆ QgsInvertedPolygonRenderer() [1/2]

QgsInvertedPolygonRenderer::QgsInvertedPolygonRenderer ( QgsFeatureRenderer * embeddedRenderer = nullptr )

Constructor.

Parameters

embeddedRenderer optional embeddedRenderer. If nullptr, a default one will be assigned. Ownership will be transferred.

Definition at line 33 of file qgsinvertedpolygonrenderer.cpp.

◆ QgsInvertedPolygonRenderer() [2/2]

QgsInvertedPolygonRenderer::QgsInvertedPolygonRenderer ( const QgsInvertedPolygonRenderer & )

delete

Direct copies are forbidden. Use clone() instead.

Member Function Documentation

◆ clone()

QgsInvertedPolygonRenderer * QgsInvertedPolygonRenderer::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 52 of file qgsinvertedpolygonrenderer.cpp.

◆ convertFromRenderer()

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

static

Creates a QgsInvertedPolygonRenderer by a conversion from an existing renderer.

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

Definition at line 101 of file qgsinvertedpolygonrenderer.cpp.

◆ create()

QgsFeatureRenderer * QgsInvertedPolygonRenderer::create	(	QDomElement &	element,
		const QgsReadWriteContext &	context
	)

static

Creates a renderer out of an XML, for loading.

Definition at line 68 of file qgsinvertedpolygonrenderer.cpp.

◆ dump()

QString QgsInvertedPolygonRenderer::dump ( ) const

overridevirtual

Returns debug information about this renderer.

Reimplemented from QgsFeatureRenderer.

Definition at line 43 of file qgsinvertedpolygonrenderer.cpp.

◆ operator=()

QgsInvertedPolygonRenderer & QgsInvertedPolygonRenderer::operator= ( const QgsInvertedPolygonRenderer & )

delete

Direct copies are forbidden. Use clone() instead.

◆ preprocessingEnabled()

bool QgsInvertedPolygonRenderer::preprocessingEnabled ( ) const

inline

Returns: true if the geometries are to be preprocessed (merged with an union) before rendering.

Definition at line 67 of file qgsinvertedpolygonrenderer.h.

◆ save()

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

overridevirtual

Stores renderer properties to an XML element.

Subclasses which override this method should call saveRendererData() as part of their implementation in order to store all common base class properties in the returned DOM element.

Reimplemented from QgsFeatureRenderer.

Definition at line 82 of file qgsinvertedpolygonrenderer.cpp.

◆ setPreprocessingEnabled()

void QgsInvertedPolygonRenderer::setPreprocessingEnabled ( bool enabled )

inline

Parameters

enabled enables or disables the preprocessing. When enabled, geometries will be merged with an union before being rendered. It allows fixing some rendering artifacts (when rendering overlapping polygons for instance). This will involve some CPU-demanding computations and is thus disabled by default.

Definition at line 75 of file qgsinvertedpolygonrenderer.h.

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

/build/qgis-3.41.0+git20241214+cea29feecf2+99sid/src/core/symbology/qgsinvertedpolygonrenderer.h
/build/qgis-3.41.0+git20241214+cea29feecf2+99sid/src/core/symbology/qgsinvertedpolygonrenderer.cpp

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsInvertedPolygonRenderer() [1/2]

◆ QgsInvertedPolygonRenderer() [2/2]

Member Function Documentation

◆ clone()

◆ convertFromRenderer()

◆ create()

◆ dump()

◆ operator=()

◆ preprocessingEnabled()

◆ save()

◆ setPreprocessingEnabled()