QGIS API Documentation  3.37.0-Master (a5b4d9743e8)
Public Member Functions | Static Public Member Functions | List of all members
QgsInvertedPolygonRenderer Class Reference

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:
Inheritance graph
[legend]

Public Member Functions

 QgsInvertedPolygonRenderer (const QgsInvertedPolygonRenderer &)=delete
 Direct copies are forbidden. Use clone() instead. More...
 
 QgsInvertedPolygonRenderer (QgsFeatureRenderer *embeddedRenderer=nullptr)
 Constructor. More...
 
QgsInvertedPolygonRendererclone () const override
 Create a deep copy of this renderer. More...
 
QString dump () const override
 Returns debug information about this renderer. More...
 
QgsInvertedPolygonRendereroperator= (const QgsInvertedPolygonRenderer &)=delete
 Direct copies are forbidden. Use clone() instead. More...
 
bool preprocessingEnabled () const
 
QDomElement save (QDomDocument &doc, const QgsReadWriteContext &context) override
 Stores renderer properties to an XML element. More...
 
void setPreprocessingEnabled (bool enabled)
 
- Public Member Functions inherited from QgsMergedFeatureRenderer
 QgsMergedFeatureRenderer (const QgsMergedFeatureRenderer &)=delete
 Direct copies are forbidden. Use clone() instead. More...
 
 QgsMergedFeatureRenderer (QgsFeatureRenderer *embeddedRenderer)
 Constructor for QgsMergedFeatureRenderer. More...
 
bool accept (QgsStyleEntityVisitorInterface *visitor) const override
 Accepts the specified symbology visitor, causing it to visit all symbols associated with the renderer. More...
 
QgsFeatureRenderer::Capabilities capabilities () override
 Returns details about internals of this renderer. More...
 
void checkLegendSymbolItem (const QString &key, bool state=true) override
 Sets whether the legend symbology item with the specified ley should be checked. More...
 
QgsMergedFeatureRendererclone () const override
 Create a deep copy of this renderer. More...
 
QString dump () const override
 Returns debug information about this renderer. More...
 
const QgsFeatureRendererembeddedRenderer () const override
 Returns the current embedded renderer (subrenderer) for this feature renderer. More...
 
bool filterNeedsGeometry () const override
 Returns true if this renderer requires the geometry to apply the filter. More...
 
QSet< QString > legendKeysForFeature (const QgsFeature &feature, QgsRenderContext &context) const override
 Returns legend keys matching a specified feature. More...
 
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. More...
 
bool legendSymbolItemChecked (const QString &key) override
 Returns true if the legend symbology item with the specified key is checked. More...
 
QgsLegendSymbolList legendSymbolItems () const override
 Returns a list of symbology items for the legend. More...
 
bool legendSymbolItemsCheckable () const override
 Returns true if symbology items in legend are checkable. More...
 
QgsMergedFeatureRendereroperator= (const QgsMergedFeatureRenderer &)=delete
 Direct copies are forbidden. Use clone() instead. More...
 
QgsSymboloriginalSymbolForFeature (const QgsFeature &feature, QgsRenderContext &context) const override
 Returns symbol for feature. More...
 
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() More...
 
bool renderFeature (const QgsFeature &feature, QgsRenderContext &context, int layer=-1, bool selected=false, bool drawVertexMarker=false) override
 Renders a given feature. More...
 
QDomElement save (QDomDocument &doc, const QgsReadWriteContext &context) override
 Stores renderer properties to an XML element. More...
 
void setEmbeddedRenderer (QgsFeatureRenderer *subRenderer) override
 Sets an embedded renderer (subrenderer) for this feature renderer. More...
 
void setLegendSymbolItem (const QString &key, QgsSymbol *symbol) override
 Sets the symbol to be used for a legend symbol item. 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
 The actual rendering will take place here. More...
 
QgsSymbolsymbolForFeature (const QgsFeature &feature, QgsRenderContext &context) const override
 To be overridden. More...
 
QgsSymbolList symbols (QgsRenderContext &context) const override
 Returns list of symbols used by the renderer. More...
 
QgsSymbolList symbolsForFeature (const QgsFeature &feature, QgsRenderContext &context) const override
 Returns list of symbols used for rendering the feature. More...
 
QSet< QString > usedAttributes (const QgsRenderContext &context) const override
 Returns a list of attributes required by this renderer. More...
 
bool willRenderFeature (const QgsFeature &feature, QgsRenderContext &context) const override
 Returns whether the renderer will render a feature or not. More...
 
- Public Member Functions inherited from QgsFeatureRenderer
virtual ~QgsFeatureRenderer ()
 
virtual bool canSkipRender ()
 Returns true if the renderer can be entirely skipped, i.e. More...
 
void copyRendererData (QgsFeatureRenderer *destRenderer) const
 Clones generic renderer data to another renderer. More...
 
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. 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...
 
QSet< QString > legendKeys () const
 Returns the set of all legend keys used by the renderer. 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
 Gets 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...
 
QgsPaintEffectpaintEffect () const
 Returns the current paint effect for the renderer. More...
 
double referenceScale () const
 Returns the symbology reference scale. 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 setReferenceScale (double scale)
 Sets the symbology reference scale. More...
 
void setUsingSymbolLevels (bool usingSymbolLevels)
 
void setVertexMarkerAppearance (Qgis::VertexMarkerType type, double size)
 Sets type and size of editing vertex markers for subsequent rendering. More...
 
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 More...
 
QString type () const
 
virtual bool usesEmbeddedSymbols () const
 Returns true if the renderer uses embedded symbols for features. More...
 
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 More...
 

Static Public Member Functions

static QgsInvertedPolygonRendererconvertFromRenderer (const QgsFeatureRenderer *renderer)
 Creates a QgsInvertedPolygonRenderer by a conversion from an existing renderer. More...
 
static QgsFeatureRenderercreate (QDomElement &element, const QgsReadWriteContext &context)
 Creates a renderer out of an XML, for loading. More...
 
- Static Public Member Functions inherited from QgsMergedFeatureRenderer
static QgsMergedFeatureRendererconvertFromRenderer (const QgsFeatureRenderer *renderer)
 Creates a QgsMergedFeatureRenderer by a conversion from an existing renderer. More...
 
static QgsFeatureRenderercreate (QDomElement &element, const QgsReadWriteContext &context)
 Creates a renderer out of an XML, for loading. More...
 
- Static Public Member Functions inherited from QgsFeatureRenderer
static QgsFeatureRendererdefaultRenderer (Qgis::GeometryType geomType)
 Returns a new renderer - used by default in vector layers. More...
 
static QgsFeatureRendererload (QDomElement &symbologyElem, const QgsReadWriteContext &context)
 create a renderer from XML element More...
 
static QgsFeatureRendererloadSld (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. More...
 

Additional Inherited Members

- Public Types inherited from QgsFeatureRenderer
typedef QFlags< CapabilityCapabilities
 
enum  Capability { SymbolLevels = 1 , MoreSymbolsPerFeature = 1 << 2 , Filter = 1 << 3 , ScaleDependent = 1 << 4 }
 Used to specify details about a renderer. 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. More...
 
- 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. More...
 
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...
 
void saveRendererData (QDomDocument &doc, QDomElement &element, const QgsReadWriteContext &context)
 Saves generic renderer data into the specified element. 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, Qgis::ScaleMethod method, const QString &field)
 
- Protected Attributes inherited from QgsMergedFeatureRenderer
GeometryOperation mOperation = Merge
 Operation to apply to collected geometries. More...
 
std::unique_ptr< QgsFeatureRenderermSubRenderer
 Embedded renderer. More...
 
- Protected Attributes inherited from QgsFeatureRenderer
double mCurrentVertexMarkerSize = 2
 The current size of editing marker. More...
 
Qgis::VertexMarkerType mCurrentVertexMarkerType = Qgis::VertexMarkerType::Cross
 The current type of editing marker. More...
 
bool mForceRaster = false
 
QgsFeatureRequest::OrderBy mOrderBy
 
bool mOrderByEnabled = false
 
QgsPaintEffectmPaintEffect = 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
embeddedRendereroptional 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
enabledenables 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: