QGIS API Documentation  3.13.0-Master (13337b20cd)
Classes | Public Types | Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
QgsPointDistanceRenderer Class Referenceabstract

An abstract base class for distance based point renderers (e.g., clusterer and displacement renderers). More...

#include <qgspointdistancerenderer.h>

Inheritance diagram for QgsPointDistanceRenderer:
Inheritance graph
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Classes

struct  GroupedFeature
 Contains properties for a feature within a clustered group. More...
 

Public Types

typedef QList< QgsPointDistanceRenderer::GroupedFeatureClusteredGroup
 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...
 

Public Member Functions

 QgsPointDistanceRenderer (const QString &rendererName, const QString &labelAttributeName=QString())
 Constructor for QgsPointDistanceRenderer. 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) override
 item in symbology was checked More...
 
const QgsFeatureRendererembeddedRenderer () 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...
 
bool filterNeedsGeometry () const override
 Returns true if this renderer requires the geometry to apply the filter. 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 (const QgsFeature &feature, QgsRenderContext &context) const override
 Returns 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...
 
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 SIP_THROW(QgsCsException)
 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...
 
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...
 
double tolerance () const
 Returns the tolerance distance for grouping points. More...
 
const QgsMapUnitScaletoleranceMapUnitScale () 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
 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 QgsFeatureRendererclone () const =0
 Create a deep copy of this renderer. More...
 
virtual QString dump () const
 Returns debug information about this renderer. 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
 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...
 
virtual QDomElement save (QDomDocument &doc, const QgsReadWriteContext &context)
 store renderer info to XML element 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, double size)
 Sets 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...
 

Protected Member Functions

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 (const QgsFeature &feature, QgsSymbol *symbol, QgsRenderContext &context, int layer, bool selected, bool drawVertexMarker) SIP_THROW(QgsCsException)
 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...
 

Protected Attributes

QList< ClusteredGroupmClusteredGroups
 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, QgsPointXYmGroupLocations
 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< QgsFeatureRenderermRenderer
 Embedded base renderer. This can be used for rendering individual, isolated points. More...
 
QgsSpatialIndexmSpatialIndex = 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
double mCurrentVertexMarkerSize
 The current size of editing marker. More...
 
int mCurrentVertexMarkerType
 The current type of editing marker. More...
 
bool mForceRaster
 
QgsFeatureRequest::OrderBy mOrderBy
 
bool mOrderByEnabled
 
QgsPaintEffectmPaintEffect = nullptr
 
QString mType
 
bool mUsingSymbolLevels
 

Additional Inherited Members

- Static Public Member Functions inherited from QgsFeatureRenderer
static QgsFeatureRendererdefaultRenderer (QgsWkbTypes::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, QgsWkbTypes::GeometryType geomType, QString &errorMessage)
 Create a new renderer according to the information contained in the UserStyle element of a SLD style document. 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)
 

Detailed Description

An abstract base class for distance based point renderers (e.g., clusterer and displacement renderers).

QgsPointDistanceRenderer handles calculation of point clusters using a distance based threshold. Subclasses must implement drawGroup() to handle the rendering of individual point clusters in the desired style.

Since
QGIS 3.0

Definition at line 38 of file qgspointdistancerenderer.h.

Member Typedef Documentation

◆ ClusteredGroup

A group of clustered points (ie features within the distance tolerance).

Definition at line 77 of file qgspointdistancerenderer.h.

Constructor & Destructor Documentation

◆ QgsPointDistanceRenderer()

QgsPointDistanceRenderer::QgsPointDistanceRenderer ( const QString &  rendererName,
const QString &  labelAttributeName = QString() 
)

Constructor for QgsPointDistanceRenderer.

Parameters
rendererNamename of renderer for registry
labelAttributeNameoptional attribute for labeling points

Definition at line 32 of file qgspointdistancerenderer.cpp.

Member Function Documentation

◆ accept()

bool QgsPointDistanceRenderer::accept ( QgsStyleEntityVisitorInterface visitor) const
overridevirtual

Accepts the specified symbology visitor, causing it to visit all symbols associated with the renderer.

Returns true if the visitor should continue visiting other objects, or false if visiting should be canceled.

Since
QGIS 3.10

Reimplemented from QgsFeatureRenderer.

Definition at line 209 of file qgspointdistancerenderer.cpp.

◆ capabilities()

QgsFeatureRenderer::Capabilities QgsPointDistanceRenderer::capabilities ( )
overridevirtual

Returns details about internals of this renderer.

E.g. if you only want to deal with visible features:

if not renderer.capabilities().testFlag(QgsFeatureRenderer.Filter) or renderer.willRenderFeature(feature, context):
deal_with_my_feature()
else:
skip_the_curren_feature()

Reimplemented from QgsFeatureRenderer.

Definition at line 237 of file qgspointdistancerenderer.cpp.

◆ checkLegendSymbolItem()

void QgsPointDistanceRenderer::checkLegendSymbolItem ( const QString &  key,
bool  state 
)
overridevirtual

item in symbology was checked

Since
QGIS 2.5

Reimplemented from QgsFeatureRenderer.

Definition at line 193 of file qgspointdistancerenderer.cpp.

◆ drawLabels()

void QgsPointDistanceRenderer::drawLabels ( QPointF  centerPoint,
QgsSymbolRenderContext context,
const QList< QPointF > &  labelShifts,
const ClusteredGroup group 
)
protected

Renders the labels for a group.

Parameters
centerPointcenter point of group
contextdestination render context
labelShiftsdisplacement for individual label positions
groupgroup of clustered features to label
Note
may not be available in Python bindings on some platforms

Definition at line 400 of file qgspointdistancerenderer.cpp.

◆ embeddedRenderer()

const QgsFeatureRenderer * QgsPointDistanceRenderer::embeddedRenderer ( ) const
overridevirtual

Returns the current embedded renderer (subrenderer) for this feature renderer.

The base class implementation does not use subrenderers and will always return nullptr.

See also
setEmbeddedRenderer()
Since
QGIS 2.16

Reimplemented from QgsFeatureRenderer.

Definition at line 164 of file qgspointdistancerenderer.cpp.

◆ filter()

QString QgsPointDistanceRenderer::filter ( const QgsFields fields = QgsFields())
overridevirtual

If a renderer does not require all the features this method may be overridden and return an expression used as where clause.

This will be called once after startRender() and before the first call to renderFeature(). By default this returns a null string and all features will be requested. You do not need to specify the extent in here, this is taken care of separately and will be combined with a filter returned from this method.

Returns
An expression used as where clause

Reimplemented from QgsFeatureRenderer.

Definition at line 201 of file qgspointdistancerenderer.cpp.

◆ filterNeedsGeometry()

bool QgsPointDistanceRenderer::filterNeedsGeometry ( ) const
overridevirtual

Returns true if this renderer requires the geometry to apply the filter.

Reimplemented from QgsFeatureRenderer.

Definition at line 232 of file qgspointdistancerenderer.cpp.

◆ labelAttributeName()

QString QgsPointDistanceRenderer::labelAttributeName ( ) const
inline

Returns the attribute name used for labeling points, or an empty string if no labeling will be done by the renderer.

See also
setLabelAttributeName()
labelFont()
minimumLabelScale()
labelColor()

Definition at line 128 of file qgspointdistancerenderer.h.

◆ labelColor()

QColor QgsPointDistanceRenderer::labelColor ( ) const
inline

Returns the color used for for labeling points.

See also
setLabelColor()
labelAttributeName()
labelFont()

Definition at line 178 of file qgspointdistancerenderer.h.

◆ labelFont()

QFont QgsPointDistanceRenderer::labelFont ( ) const
inline

Returns the font used for labeling points.

See also
setLabelFont()
labelAttributeName()
labelColor()

Definition at line 145 of file qgspointdistancerenderer.h.

◆ legendKeysForFeature()

QSet< QString > QgsPointDistanceRenderer::legendKeysForFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

Returns legend keys matching a specified feature.

Since
QGIS 2.14

Reimplemented from QgsFeatureRenderer.

Definition at line 287 of file qgspointdistancerenderer.cpp.

◆ legendSymbolItemChecked()

bool QgsPointDistanceRenderer::legendSymbolItemChecked ( const QString &  key)
overridevirtual

items of symbology items in legend is checked

Since
QGIS 2.5

Reimplemented from QgsFeatureRenderer.

Definition at line 185 of file qgspointdistancerenderer.cpp.

◆ legendSymbolItems()

QgsLegendSymbolList QgsPointDistanceRenderer::legendSymbolItems ( ) const
overridevirtual

Returns a list of symbology items for the legend.

Since
QGIS 2.6

Reimplemented from QgsFeatureRenderer.

Definition at line 358 of file qgspointdistancerenderer.cpp.

◆ legendSymbolItemsCheckable()

bool QgsPointDistanceRenderer::legendSymbolItemsCheckable ( ) const
overridevirtual

items of symbology items in legend should be checkable

Since
QGIS 2.5

Reimplemented from QgsFeatureRenderer.

Definition at line 177 of file qgspointdistancerenderer.cpp.

◆ minimumLabelScale()

double QgsPointDistanceRenderer::minimumLabelScale ( ) const
inline

Returns the minimum map scale (i.e.

most "zoomed out") at which points should be labeled by the renderer. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map.

See also
setMinimumLabelScale()
labelAttributeName()

Definition at line 161 of file qgspointdistancerenderer.h.

◆ originalSymbolForFeature()

QgsSymbol * QgsPointDistanceRenderer::originalSymbolForFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

Returns symbol for feature.

The difference compared to symbolForFeature() is that it returns original symbol which can be used as an identifier for renderer's rule - the former may return a temporary replacement of a symbol for use in rendering.

Since
QGIS 2.12

Reimplemented from QgsFeatureRenderer.

Definition at line 264 of file qgspointdistancerenderer.cpp.

◆ originalSymbolsForFeature()

QgsSymbolList QgsPointDistanceRenderer::originalSymbolsForFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

Equivalent of originalSymbolsForFeature() call extended to support renderers that may use more symbols per feature - similar to symbolsForFeature()

Since
QGIS 2.12

Reimplemented from QgsFeatureRenderer.

Definition at line 280 of file qgspointdistancerenderer.cpp.

◆ renderFeature()

bool QgsPointDistanceRenderer::renderFeature ( const QgsFeature feature,
QgsRenderContext context,
int  layer = -1,
bool  selected = false,
bool  drawVertexMarker = false 
)
overridevirtual

Render a feature using this renderer in the given context.

Must be called between startRender() and stopRender() calls. Default implementation renders a symbol as determined by symbolForFeature() call. Returns true if the feature has been returned (this is used for example to determine whether the feature may be labelled).

If layer is not -1, the renderer should draw only a particula layer from symbols (in order to support symbol level rendering).

See also
startRender()
stopRender()

Reimplemented from QgsFeatureRenderer.

Definition at line 50 of file qgspointdistancerenderer.cpp.

◆ setEmbeddedRenderer()

void QgsPointDistanceRenderer::setEmbeddedRenderer ( QgsFeatureRenderer subRenderer)
overridevirtual

Sets an embedded renderer (subrenderer) for this feature renderer.

The base class implementation does nothing with subrenderers, but individual derived classes can use these to modify their behavior.

Parameters
subRendererthe embedded renderer. Ownership will be transferred.
See also
embeddedRenderer()
Since
QGIS 2.16

Reimplemented from QgsFeatureRenderer.

Definition at line 159 of file qgspointdistancerenderer.cpp.

◆ setLabelAttributeName()

void QgsPointDistanceRenderer::setLabelAttributeName ( const QString &  name)
inline

Sets the attribute name for labeling points.

Parameters
nameattribute name, or empty string to avoid labeling features by the renderer
See also
labelAttributeName()
setLabelFont()
setLabelColor()
setMinimumLabelScale()

Definition at line 118 of file qgspointdistancerenderer.h.

◆ setLabelColor()

void QgsPointDistanceRenderer::setLabelColor ( const QColor &  color)
inline

Sets the color to use for for labeling points.

Parameters
colorlabel color
See also
labelColor()
setLabelAttributeName()
setLabelFont()

Definition at line 170 of file qgspointdistancerenderer.h.

◆ setLabelFont()

void QgsPointDistanceRenderer::setLabelFont ( const QFont &  font)
inline

Sets the font used for labeling points.

Parameters
fontlabel font
See also
labelFont()
setLabelAttributeName()
setLabelColor()

Definition at line 137 of file qgspointdistancerenderer.h.

◆ setLegendSymbolItem()

void QgsPointDistanceRenderer::setLegendSymbolItem ( const QString &  key,
QgsSymbol symbol 
)
overridevirtual

Sets the symbol to be used for a legend symbol item.

Parameters
keyrule key for legend symbol
symbolnew symbol for legend item. Ownership is transferred to renderer.
Since
QGIS 2.14

Reimplemented from QgsFeatureRenderer.

Definition at line 169 of file qgspointdistancerenderer.cpp.

◆ setMinimumLabelScale()

void QgsPointDistanceRenderer::setMinimumLabelScale ( double  scale)
inline

Sets the minimum map scale (i.e.

most "zoomed out") at which points should be labeled by the renderer. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map.

See also
minimumLabelScale()
setLabelAttributeName()

Definition at line 153 of file qgspointdistancerenderer.h.

◆ setTolerance()

void QgsPointDistanceRenderer::setTolerance ( double  distance)
inline

Sets the tolerance distance for grouping points.

Units are specified using setToleranceUnit().

Parameters
distancetolerance distance
See also
tolerance()
setToleranceUnit()

Definition at line 187 of file qgspointdistancerenderer.h.

◆ setToleranceMapUnitScale()

void QgsPointDistanceRenderer::setToleranceMapUnitScale ( const QgsMapUnitScale scale)
inline

Sets the map unit scale object for the distance tolerance.

This is only used if the toleranceUnit() is set to QgsUnitTypes::RenderMapUnits.

Parameters
scalescale for distance tolerance
See also
toleranceMapUnitScale()
setToleranceUnit()

Definition at line 221 of file qgspointdistancerenderer.h.

◆ setToleranceUnit()

void QgsPointDistanceRenderer::setToleranceUnit ( QgsUnitTypes::RenderUnit  unit)
inline

Sets the units for the tolerance distance.

Parameters
unittolerance distance units
See also
setTolerance()
toleranceUnit()
Since
QGIS 2.12

Definition at line 204 of file qgspointdistancerenderer.h.

◆ startRender()

void QgsPointDistanceRenderer::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
contextAdditional information passed to the renderer about the job which will be rendered
fieldsThe 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 304 of file qgspointdistancerenderer.cpp.

◆ stopRender()

void QgsPointDistanceRenderer::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.
See also
startRender()

Reimplemented from QgsFeatureRenderer.

Definition at line 334 of file qgspointdistancerenderer.cpp.

◆ symbolForFeature()

QgsSymbol * QgsPointDistanceRenderer::symbolForFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

To be overridden.

Must be called between startRender() and stopRender() calls.

Parameters
featurefeature
contextrender context
Returns
returns pointer to symbol or 0 if symbol was not found
Since
QGIS 2.12

Implements QgsFeatureRenderer.

Definition at line 255 of file qgspointdistancerenderer.cpp.

◆ symbols()

QgsSymbolList QgsPointDistanceRenderer::symbols ( QgsRenderContext context) const
overridevirtual

Returns list of symbols used by the renderer.

Parameters
contextrender context
Since
QGIS 2.12

Reimplemented from QgsFeatureRenderer.

Definition at line 246 of file qgspointdistancerenderer.cpp.

◆ symbolsForFeature()

QgsSymbolList QgsPointDistanceRenderer::symbolsForFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

Returns list of symbols used for rendering the feature.

For renderers that do not support MoreSymbolsPerFeature it is more efficient to use symbolForFeature()

Since
QGIS 2.12

Reimplemented from QgsFeatureRenderer.

Definition at line 271 of file qgspointdistancerenderer.cpp.

◆ tolerance()

double QgsPointDistanceRenderer::tolerance ( ) const
inline

Returns the tolerance distance for grouping points.

Units are retrieved using toleranceUnit().

See also
setTolerance()
toleranceUnit()

Definition at line 195 of file qgspointdistancerenderer.h.

◆ toleranceMapUnitScale()

const QgsMapUnitScale& QgsPointDistanceRenderer::toleranceMapUnitScale ( ) const
inline

Returns the map unit scale object for the distance tolerance.

This is only used if the toleranceUnit() is set to QgsUnitTypes::RenderMapUnits.

See also
setToleranceMapUnitScale()
toleranceUnit()

Definition at line 229 of file qgspointdistancerenderer.h.

◆ toleranceUnit()

QgsUnitTypes::RenderUnit QgsPointDistanceRenderer::toleranceUnit ( ) const
inline

Returns the units for the tolerance distance.

See also
tolerance()
setToleranceUnit()
Since
QGIS 2.12

Definition at line 212 of file qgspointdistancerenderer.h.

◆ toSld()

void QgsPointDistanceRenderer::toSld ( QDomDocument &  doc,
QDomElement &  element,
const QgsStringMap props = QgsStringMap() 
) const
overridevirtual

used from subclasses to create SLD Rule elements following SLD v1.1 specs

Reimplemented from QgsFeatureRenderer.

Definition at line 44 of file qgspointdistancerenderer.cpp.

◆ usedAttributes()

QSet< QString > QgsPointDistanceRenderer::usedAttributes ( const QgsRenderContext context) const
overridevirtual

Returns a list of attributes required by this renderer.

Attributes not listed in here may not have been requested from the provider at rendering time.

Returns
A set of attributes

Implements QgsFeatureRenderer.

Definition at line 218 of file qgspointdistancerenderer.cpp.

◆ willRenderFeature()

bool QgsPointDistanceRenderer::willRenderFeature ( const QgsFeature feature,
QgsRenderContext context 
) const
overridevirtual

Returns whether the renderer will render a feature or not.

Must be called between startRender() and stopRender() calls. Default implementation uses symbolForFeature().

Since
QGIS 2.12

Reimplemented from QgsFeatureRenderer.

Definition at line 294 of file qgspointdistancerenderer.cpp.

Member Data Documentation

◆ mClusteredGroups

QList<ClusteredGroup> QgsPointDistanceRenderer::mClusteredGroups
protected

Groups of features that are considered clustered together.

Definition at line 259 of file qgspointdistancerenderer.h.

◆ mDrawLabels

bool QgsPointDistanceRenderer::mDrawLabels
protected

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

Definition at line 254 of file qgspointdistancerenderer.h.

◆ mGroupIndex

QMap<QgsFeatureId, int> QgsPointDistanceRenderer::mGroupIndex
protected

Mapping of feature ID to the feature's group index.

Definition at line 262 of file qgspointdistancerenderer.h.

◆ mGroupLocations

QMap<QgsFeatureId, QgsPointXY > QgsPointDistanceRenderer::mGroupLocations
protected

Mapping of feature ID to approximate group location.

Definition at line 265 of file qgspointdistancerenderer.h.

◆ mLabelAttributeName

QString QgsPointDistanceRenderer::mLabelAttributeName
protected

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

Definition at line 237 of file qgspointdistancerenderer.h.

◆ mLabelColor

QColor QgsPointDistanceRenderer::mLabelColor
protected

Label text color.

Definition at line 252 of file qgspointdistancerenderer.h.

◆ mLabelFont

QFont QgsPointDistanceRenderer::mLabelFont
protected

Label font.

Definition at line 250 of file qgspointdistancerenderer.h.

◆ mLabelIndex

int QgsPointDistanceRenderer::mLabelIndex
protected

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

Definition at line 240 of file qgspointdistancerenderer.h.

◆ mMinLabelScale

double QgsPointDistanceRenderer::mMinLabelScale = 0
protected

Maximum scale denominator for label display. A zero value indicates no scale limitation.

Definition at line 256 of file qgspointdistancerenderer.h.

◆ mRenderer

std::unique_ptr< QgsFeatureRenderer > QgsPointDistanceRenderer::mRenderer
protected

Embedded base renderer. This can be used for rendering individual, isolated points.

Definition at line 234 of file qgspointdistancerenderer.h.

◆ mSpatialIndex

QgsSpatialIndex* QgsPointDistanceRenderer::mSpatialIndex = nullptr
protected

Spatial index for fast lookup of nearby points.

Definition at line 268 of file qgspointdistancerenderer.h.

◆ mTolerance

double QgsPointDistanceRenderer::mTolerance
protected

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

Definition at line 243 of file qgspointdistancerenderer.h.

◆ mToleranceMapUnitScale

QgsMapUnitScale QgsPointDistanceRenderer::mToleranceMapUnitScale
protected

Map unit scale for distance tolerance.

Definition at line 247 of file qgspointdistancerenderer.h.

◆ mToleranceUnit

QgsUnitTypes::RenderUnit QgsPointDistanceRenderer::mToleranceUnit
protected

Unit for distance tolerance.

Definition at line 245 of file qgspointdistancerenderer.h.


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