36static bool _palIsCanceled(
void *ctx )
38 return (
reinterpret_cast< QgsRenderContext *
>( ctx ) )->renderingStopped();
52 explicit QgsLabelSorter(
const QStringList &layerRenderingOrderIds )
53 : mLayerRenderingOrderIds( layerRenderingOrderIds )
65 int layer1Pos = mLayerRenderingOrderIds.indexOf( lf1->
provider()->
layerId() );
66 int layer2Pos = mLayerRenderingOrderIds.indexOf( lf2->
provider()->
layerId() );
67 if ( layer1Pos != layer2Pos && layer1Pos >= 0 && layer2Pos >= 0 )
68 return layer1Pos > layer2Pos;
71 return lf1->
size().width() * lf1->
size().height() > lf2->
size().width() * lf2->
size().height();
76 const QStringList mLayerRenderingOrderIds;
105 QList< QgsMapLayer * > layers;
108 QList< QgsAbstractLabelProvider * > providersByZ =
mProviders;
109 std::sort( providersByZ.begin(), providersByZ.end(),
112 const QgsVectorLayerLabelProvider *providerA = dynamic_cast<const QgsVectorLayerLabelProvider *>( a );
113 const QgsVectorLayerLabelProvider *providerB = dynamic_cast<const QgsVectorLayerLabelProvider *>( b );
115 if ( providerA && providerB )
117 return providerA->settings().zIndex < providerB->settings().zIndex ;
122 QList< QgsAbstractLabelProvider * > subProvidersByZ = mSubProviders;
123 std::sort( subProvidersByZ.begin(), subProvidersByZ.end(),
126 const QgsVectorLayerLabelProvider *providerA = dynamic_cast<const QgsVectorLayerLabelProvider *>( a );
127 const QgsVectorLayerLabelProvider *providerB = dynamic_cast<const QgsVectorLayerLabelProvider *>( b );
129 if ( providerA && providerB )
131 return providerA->settings().zIndex < providerB->settings().zIndex ;
138 if ( provider->layer() && !layers.contains( provider->layer() ) )
139 layers << provider->layer();
143 if ( provider->layer() && !layers.contains( provider->layer() ) )
144 layers << provider->layer();
154 QList< QgsAbstractLabelProvider * > providersByZ =
mProviders;
155 std::sort( providersByZ.begin(), providersByZ.end(),
158 const QgsVectorLayerLabelProvider *providerA = dynamic_cast<const QgsVectorLayerLabelProvider *>( a );
159 const QgsVectorLayerLabelProvider *providerB = dynamic_cast<const QgsVectorLayerLabelProvider *>( b );
161 if ( providerA && providerB )
163 return providerA->settings().zIndex < providerB->settings().zIndex ;
168 QList< QgsAbstractLabelProvider * > subProvidersByZ = mSubProviders;
169 std::sort( subProvidersByZ.begin(), subProvidersByZ.end(),
172 const QgsVectorLayerLabelProvider *providerA = dynamic_cast<const QgsVectorLayerLabelProvider *>( a );
173 const QgsVectorLayerLabelProvider *providerB = dynamic_cast<const QgsVectorLayerLabelProvider *>( b );
175 if ( providerA && providerB )
177 return providerA->settings().zIndex < providerB->settings().zIndex ;
184 if ( !layers.contains( provider->layerId() ) )
185 layers << provider->layerId();
189 if ( !layers.contains( provider->layerId() ) )
190 layers << provider->layerId();
212 QgsAbstractLabelProvider::Flags flags = provider->
flags();
234 const QList<QgsLabelFeature *> features = provider->
labelFeatures( context );
242 catch ( std::exception &e )
245 QgsDebugMsgLevel( QStringLiteral(
"Ignoring feature %1 due PAL exception:" ).arg( feature->id() ) + QString::fromLatin1( e.what() ), 4 );
261 std::unique_ptr< QgsScopedRuntimeProfile > registeringProfile;
264 registeringProfile = std::make_unique< QgsScopedRuntimeProfile >( QObject::tr(
"Registering labels" ), QStringLiteral(
"rendering" ) );
270 feedback->emit labelRegistrationAboutToBegin();
274 mPal = std::make_unique< pal::Pal >();
289 feedback->emit providerRegistrationAboutToBegin( provider );
293 std::unique_ptr< QgsExpressionContextScopePopper > layerScopePopper;
294 if ( provider->layerExpressionContextScope() )
300 feedback->emit providerRegistrationFinished( provider );
303 feedback->emit labelRegistrationFinished();
308 Q_ASSERT(
mPal.get() );
313 QPainter *painter = context.
painter();
320 visiblePoly.append( visiblePoly.at( 0 ) );
329 mapBoundaryGeom = mapBoundaryGeom.
difference( region.geometry );
337 QVariantMap properties;
338 properties.insert( QStringLiteral(
"style" ), QStringLiteral(
"no" ) );
339 properties.insert( QStringLiteral(
"style_border" ), QStringLiteral(
"solid" ) );
340 properties.insert( QStringLiteral(
"color_border" ), QStringLiteral(
"#0000ff" ) );
341 properties.insert( QStringLiteral(
"width_border" ), QStringLiteral(
"0.3" ) );
342 properties.insert( QStringLiteral(
"joinstyle" ), QStringLiteral(
"miter" ) );
344 boundarySymbol->startRender( context );
345 boundarySymbol->renderFeature( f, context );
346 boundarySymbol->stopRender( context );
359 mPal->registerCancellationCallback( &_palIsCanceled,
reinterpret_cast< void *
>( &context ) );
367 mProblem =
mPal->extractProblem( extent, mapBoundaryGeom, context );
369 catch ( std::exception &e )
372 QgsDebugMsgLevel(
"PAL EXCEPTION :-( " + QString::fromLatin1( e.what() ), 4 );
398 painter->setBrush( Qt::NoBrush );
399 for (
int i = 0; i < static_cast< int >(
mProblem->featureCount() ); i++ )
401 for (
int j = 0; j <
mProblem->featureCandidateCount( i ); j++ )
417 std::sort(
mLabels.begin(),
mLabels.end(), QgsLabelSorter( mLayerRenderingOrderIds ) );
419 QgsDebugMsgLevel( QStringLiteral(
"LABELING work: %1 ms ... labels# %2" ).arg( t.elapsed() ).arg(
mLabels.size() ), 4 );
427 std::unique_ptr< QgsScopedRuntimeProfile > drawingProfile;
430 drawingProfile = std::make_unique< QgsScopedRuntimeProfile >( QObject::tr(
"Rendering labels" ), QStringLiteral(
"rendering" ) );
436 QPainter *painter = context.
painter();
441 if ( !layerId.isEmpty() && provider->layerId() != layerId )
449 provider->startRender( context );
453 std::unique_ptr< QgsExpressionContextScopePopper > symbolScopePopper = std::make_unique< QgsExpressionContextScopePopper >( context.
expressionContext(), symbolScope );
540 symbolScopePopper.reset();
545 if ( !layerId.isEmpty() && provider->layerId() != layerId )
548 provider->stopRender( context );
552 painter->setCompositionMode( QPainter::CompositionMode_SourceOver );
554 QgsDebugMsgLevel( QStringLiteral(
"LABELING draw: %1 ms" ).arg( t.elapsed() ), 4 );
650 : mLayerId( layer ? layer->id() : QString() )
652 , mProviderId( providerId )
656 mLayerExpressionContextScope.reset( vl->createExpressionContextScope() );
658 mLayerReferenceScale = renderer->referenceScale();
677 subProvider->startRender( context );
686 subProvider->stopRender( context );
692 return mLayerExpressionContextScope.get();
701 QStringList predefinedOrderString;
702 const auto constPositions = positions;
708 predefinedOrderString << QStringLiteral(
"TL" );
711 predefinedOrderString << QStringLiteral(
"TSL" );
714 predefinedOrderString << QStringLiteral(
"T" );
717 predefinedOrderString << QStringLiteral(
"TSR" );
720 predefinedOrderString << QStringLiteral(
"TR" );
723 predefinedOrderString << QStringLiteral(
"L" );
726 predefinedOrderString << QStringLiteral(
"R" );
729 predefinedOrderString << QStringLiteral(
"BL" );
732 predefinedOrderString << QStringLiteral(
"BSL" );
735 predefinedOrderString << QStringLiteral(
"B" );
738 predefinedOrderString << QStringLiteral(
"BSR" );
741 predefinedOrderString << QStringLiteral(
"BR" );
745 return predefinedOrderString.join(
',' );
750 QVector<Qgis::LabelPredefinedPointPosition> result;
751 const QStringList predefinedOrderList = positionString.split(
',' );
752 result.reserve( predefinedOrderList.size() );
753 for (
const QString &position : predefinedOrderList )
755 QString cleaned = position.trimmed().toUpper();
756 if ( cleaned == QLatin1String(
"TL" ) )
758 else if ( cleaned == QLatin1String(
"TSL" ) )
760 else if ( cleaned == QLatin1String(
"T" ) )
762 else if ( cleaned == QLatin1String(
"TSR" ) )
764 else if ( cleaned == QLatin1String(
"TR" ) )
766 else if ( cleaned == QLatin1String(
"L" ) )
768 else if ( cleaned == QLatin1String(
"R" ) )
770 else if ( cleaned == QLatin1String(
"BL" ) )
772 else if ( cleaned == QLatin1String(
"BSL" ) )
774 else if ( cleaned == QLatin1String(
"B" ) )
776 else if ( cleaned == QLatin1String(
"BSR" ) )
778 else if ( cleaned == QLatin1String(
"BR" ) )
788 parts << QStringLiteral(
"OL" );
790 parts << QStringLiteral(
"AL" );
792 parts << QStringLiteral(
"BL" );
794 parts << QStringLiteral(
"LO" );
795 return parts.join(
',' );
800 Qgis::LabelLinePlacementFlags flags = Qgis::LabelLinePlacementFlags();
801 const QStringList flagList =
string.split(
',' );
802 bool foundLineOrientationFlag =
false;
803 for (
const QString &flag : flagList )
805 QString cleaned = flag.trimmed().toUpper();
806 if ( cleaned == QLatin1String(
"OL" ) )
808 else if ( cleaned == QLatin1String(
"AL" ) )
810 else if ( cleaned == QLatin1String(
"BL" ) )
812 else if ( cleaned == QLatin1String(
"LO" ) )
813 foundLineOrientationFlag =
true;
815 if ( !foundLineOrientationFlag )
@ BelowLine
Labels can be placed below a line feature. Unless MapOrientation is also specified this mode respects...
@ MapOrientation
Signifies that the AboveLine and BelowLine flags should respect the map's orientation rather than the...
@ OnLine
Labels can be placed directly over a line feature.
@ AboveLine
Labels can be placed above a line feature. Unless MapOrientation is also specified this mode respects...
@ DrawCandidates
Whether to draw rectangles of generated candidates (good for debugging)
@ CollectUnplacedLabels
Whether unplaced labels should be collected in the labeling results (regardless of whether they are b...
@ DrawUnplacedLabels
Whether to render unplaced labels as an indicator/warning for users.
@ UseAllLabels
Whether to draw all labels even if there would be collisions.
@ UsePartialCandidates
Whether to use also label candidates that are partially outside of the map view.
@ Millimeters
Millimeters.
@ RecordProfile
Enable run-time profiling while rendering (since QGIS 3.34)
LabelPredefinedPointPosition
Positions for labels when using the Qgis::LabelPlacement::OrderedPositionsAroundPoint placement mode.
@ MiddleLeft
Label on left of point.
@ TopRight
Label on top-right of point.
@ MiddleRight
Label on right of point.
@ TopSlightlyRight
Label on top of point, slightly right of center.
@ TopMiddle
Label directly above point.
@ BottomSlightlyLeft
Label below point, slightly left of center.
@ BottomRight
Label on bottom right of point.
@ BottomLeft
Label on bottom-left of point.
@ BottomSlightlyRight
Label below point, slightly right of center.
@ TopLeft
Label on top-left of point.
@ BottomMiddle
Label directly below point.
@ TopSlightlyLeft
Label on top of point, slightly left of center.
The QgsAbstractLabelProvider class is an interface class.
QgsExpressionContextScope * layerExpressionContextScope() const
Returns the expression context scope created from the layer associated with this provider.
virtual QList< QgsLabelFeature * > labelFeatures(QgsRenderContext &context)=0
Returns list of label features (they are owned by the provider and thus deleted on its destruction)
virtual void drawUnplacedLabel(QgsRenderContext &context, pal::LabelPosition *label) const
Draw an unplaced label.
virtual void stopRender(QgsRenderContext &context)
To be called after rendering is complete.
virtual QList< QgsAbstractLabelProvider * > subProviders()
Returns list of child providers - useful if the provider needs to put labels into more layers with di...
Qgis::LabelPlacement placement() const
What placement strategy to use for the labels.
void setEngine(const QgsLabelingEngine *engine)
Associate provider with a labeling engine (should be only called internally from QgsLabelingEngine)
virtual void drawLabel(QgsRenderContext &context, pal::LabelPosition *label) const =0
Draw this label at the position determined by the labeling engine.
double priority() const
Default priority of labels (may be overridden by individual labels)
virtual void drawLabelBackground(QgsRenderContext &context, pal::LabelPosition *label) const
Draw the background for the specified label.
QString name() const
Name of the layer (for statistics, debugging etc.) - does not need to be unique.
double layerReferenceScale() const
Returns the symbology reference scale of the layer associated with this provider.
QgsMapLayer * layer() const
Returns the associated layer, or nullptr if no layer is associated with the provider.
virtual void startRender(QgsRenderContext &context)
To be called before rendering of labels begins.
Flags flags() const
Flags associated with the provider.
QgsLabelObstacleSettings::ObstacleType obstacleType() const
How the feature geometries will work as obstacles.
@ MergeConnectedLines
Whether adjacent lines (with the same label text) should be merged.
@ DrawLabels
Whether the labels should be rendered.
@ CentroidMustBeInside
Whether location of centroid must be inside of polygons.
QString layerId() const
Returns ID of associated layer, or empty string if no layer is associated with the provider.
Qgis::UpsideDownLabelHandling upsidedownLabels() const
How to handle labels that would be upside down.
QgsAbstractLabelProvider(QgsMapLayer *layer, const QString &providerId=QString())
Construct the provider with default values.
QgsDefaultLabelingEngine()
Construct the labeling engine with default settings.
void run(QgsRenderContext &context) override
Runs the labeling job.
RAII class to pop scope from an expression context on destruction.
Single scope for storing variables and functions for use within a QgsExpressionContext.
static QgsExpressionContextScope * updateSymbolScope(const QgsSymbol *symbol, QgsExpressionContextScope *symbolScope=nullptr)
Updates a symbol scope related to a QgsSymbol to an expression context.
void setFeature(const QgsFeature &feature)
Convenience function for setting a feature for the context.
void setFields(const QgsFields &fields)
Convenience function for setting a fields for the context.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
void setProgress(double progress)
Sets the current progress for the feedback object.
static QgsFillSymbol * createSimple(const QVariantMap &properties)
Create a fill symbol with one symbol layer: SimpleFill with specified properties.
A geometry is the spatial representation of a feature.
static QgsGeometry fromRect(const QgsRectangle &rect)
Creates a new geometry from a QgsRectangle.
QgsGeometry difference(const QgsGeometry &geometry, const QgsGeometryParameters ¶meters=QgsGeometryParameters()) const
Returns a geometry representing the points making up this geometry that do not make up other.
static QgsGeometry fromQPolygonF(const QPolygonF &polygon)
Construct geometry from a QPolygonF.
QgsRectangle boundingBox() const
Returns the bounding box of the geometry.
Qgis::GeometryOperationResult rotate(double rotation, const QgsPointXY ¢er)
Rotate this geometry around the Z axis.
Label blocking region (in map coordinates and CRS).
The QgsLabelFeature class describes a feature that should be used within the labeling engine.
QSizeF size(double angle=0.0) const
Size of the label (in map units).
QgsAbstractLabelProvider * provider() const
Returns provider of this instance.
void setSymbol(const QgsSymbol *symbol)
Sets the feature symbol associated with this label.
pal::Layer * mLayer
Pointer to PAL layer (assigned when registered to PAL)
QgsFeature feature() const
Returns the original feature associated with this label.
double zIndex() const
Returns the label's z-index.
const QgsSymbol * symbol() const
Returns the feature symbol associated with this label.
QgsFeedback subclass for granular reporting of labeling engine progress.
Stores global configuration for labeling engine.
Qgis::LabelPlacementEngineVersion placementVersion() const
Returns the placement engine version, which dictates how the label placement problem is solved.
bool testFlag(Qgis::LabelingFlag f) const
Test whether a particular flag is enabled.
Qgis::LabelingFlags flags() const
Gets flags of the labeling engine.
double maximumPolygonCandidatesPerCmSquared() const
Returns the maximum number of polygon label candidate positions per centimeter squared.
double maximumLineCandidatesPerCm() const
Returns the maximum number of line label candidate positions per centimeter.
The QgsLabelingEngine class provides map labeling functionality.
std::unique_ptr< pal::Pal > mPal
std::unique_ptr< QgsLabelingResults > mResults
Resulting labeling layout.
QgsMapSettings mMapSettings
Associated map settings instance.
void solve(QgsRenderContext &context)
Solves the label problem.
QList< pal::LabelPosition * > mUnlabeled
std::unique_ptr< pal::Problem > mProblem
const QgsMapSettings & mapSettings() const
Gets associated map settings.
QList< pal::LabelPosition * > mLabels
QgsLabelingResults * takeResults()
Returns pointer to recently computed results and pass the ownership of results to the caller.
void cleanup()
Cleans up the engine following a call to registerLabels() or solve().
void setMapSettings(const QgsMapSettings &mapSettings)
Associate map settings instance.
void registerLabels(QgsRenderContext &context)
Runs the label registration step.
QList< QgsAbstractLabelProvider * > mSubProviders
void addProvider(QgsAbstractLabelProvider *provider)
Add provider of label features. Takes ownership of the provider.
void drawLabels(QgsRenderContext &context, const QString &layerId=QString())
Draws labels to the specified render context.
QStringList participatingLayerIds() const
Returns a list of layer IDs for layers with providers in the engine.
QList< QgsMapLayer * > participatingLayers() const
Returns a list of layers with providers in the engine.
void processProvider(QgsAbstractLabelProvider *provider, QgsRenderContext &context, pal::Pal &p)
QgsLabelingEngine()
Construct the labeling engine with default settings.
void removeProvider(QgsAbstractLabelProvider *provider)
Remove provider if the provider's initialization failed. Provider instance is deleted.
QList< QgsAbstractLabelProvider * > mProviders
List of providers (the are owned by the labeling engine)
virtual ~QgsLabelingEngine()
Clean up everything (especially the registered providers)
Class that stores computed placement from labeling engine.
static QString encodePredefinedPositionOrder(const QVector< Qgis::LabelPredefinedPointPosition > &positions)
Encodes an ordered list of predefined point label positions to a string.
static QVector< Qgis::LabelPredefinedPointPosition > decodePredefinedPositionOrder(const QString &positionString)
Decodes a string to an ordered list of predefined point label positions.
static Qgis::LabelLinePlacementFlags decodeLinePlacementFlags(const QString &string)
Decodes a string to set of line placement flags.
static QString encodeLinePlacementFlags(Qgis::LabelLinePlacementFlags flags)
Encodes line placement flags to a string.
Base class for all map layer types.
The QgsMapSettings class contains configuration for rendering of the map.
const QgsLabelingEngineSettings & labelingEngineSettings() const
Returns the global configuration of the labeling engine.
QgsGeometry labelBoundaryGeometry() const
Returns the label boundary geometry, which restricts where in the rendered map labels are permitted t...
QStringList layerIds(bool expandGroupLayers=false) const
Returns the list of layer IDs which will be rendered in the map.
const QgsMapToPixel & mapToPixel() const
QList< QgsLabelBlockingRegion > labelBlockingRegions() const
Returns the list of regions to avoid placing labels within.
double extentBuffer() const
Returns the buffer in map units to use around the visible extent for rendering symbols whose correspo...
QgsRectangle visibleExtent() const
Returns the actual extent derived from requested extent that takes output image size into account.
double rotation() const
Returns the rotation of the resulting map image, in degrees clockwise.
QPolygonF visiblePolygonWithBuffer() const
Returns the visible area as a polygon (may be rotated) with extent buffer included.
Perform transforms between map coordinates and device coordinates.
void setMapRotation(double degrees, double cx, double cy)
Sets map rotation in degrees (clockwise).
static void drawLabelCandidateRect(pal::LabelPosition *lp, QPainter *painter, const QgsMapToPixel *xform, QList< QgsLabelCandidate > *candidates=nullptr)
A rectangle specified with double values.
QgsPointXY center() const
Returns the center point of the rectangle.
void grow(double delta)
Grows the rectangle in place by the specified amount.
Contains information about the context of a rendering operation.
double convertToMapUnits(double size, Qgis::RenderUnit unit, const QgsMapUnitScale &scale=QgsMapUnitScale()) const
Converts a size from the specified units to map units.
QPainter * painter()
Returns the destination QPainter for the render operation.
void setPainterFlagsUsingContext(QPainter *painter=nullptr) const
Sets relevant flags on a destination painter, using the flags and settings currently defined for the ...
QgsExpressionContext & expressionContext()
Gets the expression context.
QgsFeedback * feedback() const
Returns the feedback object that can be queried regularly during rendering to check if rendering shou...
bool renderingStopped() const
Returns true if the rendering operation has been stopped and any ongoing rendering should be canceled...
Qgis::RenderContextFlags flags() const
Returns combination of flags used for rendering.
Scoped object for temporary override of the symbologyReferenceScale property of a QgsRenderContext.
void finalize()
Finalizes and cleans up the engine following the rendering of labels for the last layer to be labeled...
void run(QgsRenderContext &context) override
Runs the labeling job.
QgsStagedRenderLabelingEngine()
Construct the labeling engine with default settings.
void renderLabelsForLayer(QgsRenderContext &context, const QString &layerId)
Renders all the labels which belong only to the layer with matching layerId to the specified render c...
Represents a vector layer which manages a vector based data sets.
QgsLabelFeature * feature()
Returns the parent feature.
LabelPosition is a candidate feature label position.
FeaturePart * getFeaturePart() const
Returns the feature corresponding to this labelposition.
A set of features which influence the labeling process.
void setUpsidedownLabels(Qgis::UpsideDownLabelHandling ud)
Sets how upside down labels will be handled within the layer.
bool registerFeature(QgsLabelFeature *label)
Register a feature in the layer.
QgsAbstractLabelProvider * provider() const
Returns pointer to the associated provider.
void setObstacleType(QgsLabelObstacleSettings::ObstacleType obstacleType)
Sets the obstacle type, which controls how features within the layer act as obstacles for labels.
void setMergeConnectedLines(bool merge)
Sets whether connected lines should be merged before labeling.
void setCentroidInside(bool forceInside)
Sets whether labels placed at the centroid of features within the layer are forced to be placed insid...
Layer * addLayer(QgsAbstractLabelProvider *provider, const QString &layerName, Qgis::LabelPlacement arrangement, double defaultPriority, bool active, bool toLabel)
add a new layer
bool qgsDoubleNear(double a, double b, double epsilon=4 *std::numeric_limits< double >::epsilon())
Compare two doubles (but allow some difference)
#define QgsDebugMsgLevel(str, level)