QGIS API Documentation
3.16.0-Hannover (43b64b13f3)
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41 #include <QTextDocument>
42 #include <QTextFragment>
49 , mLayerGeometryType( layer->geometryType() )
50 , mRenderer( layer->renderer() )
51 , mFields( layer->fields() )
52 , mCrs( layer->
crs() )
56 if ( withFeatureLoop )
58 mSource = qgis::make_unique<QgsVectorLayerFeatureSource>(
layer );
67 , mLayerGeometryType( geometryType )
68 , mRenderer( nullptr )
140 QSet<QString> attrNames;
141 if ( !
prepare( ctx, attrNames ) )
142 return QList<QgsLabelFeature *>();
171 if ( !symbols.isEmpty() )
173 symbol = symbols.at( 0 );
205 std::unique_ptr< QgsAbstractGeometry > obstacleGeom;
207 obstacleGeom = qgis::make_unique< QgsMultiPolygon >();
210 for (
int i = 0; i < fet.
geometry().constGet()->nCoordinates(); ++i )
233 const auto constSymbols = symbols;
238 if ( bounds.isValid() )
239 bounds = bounds.united(
static_cast< QgsMarkerSymbol *
>( symbol )->bounds( pt, context, fet ) );
241 bounds =
static_cast< QgsMarkerSymbol *
>( symbol )->bounds( pt, context, fet );
246 QVector< double > bX;
247 bX << bounds.left() << bounds.right() << bounds.right() << bounds.left();
248 QVector< double > bY;
249 bY << bounds.top() << bounds.top() << bounds.bottom() << bounds.bottom();
250 std::unique_ptr< QgsLineString > boundLineString = qgis::make_unique< QgsLineString >( bX, bY );
254 for (
int i = 0; i < boundLineString->numPoints(); ++i )
257 static_cast<int>( boundLineString->yAt( i ) ) );
258 boundLineString->setXAt( i, point.
x() );
259 boundLineString->setYAt( i, point.
y() );
272 boundLineString->close();
277 boundLineString->filterVertices( [](
const QgsPoint & point )->
bool
279 return std::isfinite( point.
x() ) && std::isfinite( point.
y() );
281 if ( !boundLineString->isRing() )
285 std::unique_ptr< QgsPolygon > obstaclePolygon = qgis::make_unique< QgsPolygon >();
286 obstaclePolygon->setExteriorRing( boundLineString.release() );
290 static_cast<QgsMultiPolygon *
>( obstacleGeom.get() )->addGeometry( obstaclePolygon.release() );
294 obstacleGeom = std::move( obstaclePolygon );
309 drawCallout( context, label );
327 QRectF rect( outPt.x(), outPt.y(), outPt2.
x() - outPt.x(), outPt2.
y() - outPt.y() );
350 const QMap< QgsPalLayerSettings::Property, QVariant > &ddValues = lf->
dataDefinedValues();
355 QgsDebugMsgLevel( QStringLiteral(
"PAL font definedFont: %1, Style: %2" ).arg( dFont.toString(), dFont.styleName() ), 4 );
362 format.
setSize( dFont.pixelSize() );
371 case LabelPosition::QuadrantAboveLeft:
372 case LabelPosition::QuadrantLeft:
373 case LabelPosition::QuadrantBelowLeft:
376 case LabelPosition::QuadrantAbove:
377 case LabelPosition::QuadrantOver:
378 case LabelPosition::QuadrantBelow:
381 case LabelPosition::QuadrantAboveRight:
382 case LabelPosition::QuadrantRight:
383 case LabelPosition::QuadrantBelowRight:
390 QgsPalLabeling::dataDefinedTextStyle( tmpLyr, ddValues );
393 QgsPalLabeling::dataDefinedTextBuffer( tmpLyr, ddValues );
396 QgsPalLabeling::dataDefinedTextMask( tmpLyr, ddValues );
399 QgsPalLabeling::dataDefinedTextFormatting( tmpLyr, ddValues );
402 QgsPalLabeling::dataDefinedShapeBackground( tmpLyr, ddValues );
405 QgsPalLabeling::dataDefinedDropShadow( tmpLyr, ddValues );
413 drawCallout( context, label );
474 QPainter *painter = context.
painter();
492 QRectF rect( 0, 0, outPt2.
x() - outPt.x(), outPt2.
y() - outPt.y() );
494 painter->setRenderHint( QPainter::Antialiasing,
false );
495 painter->translate( QPointF( outPt.x(), outPt.y() ) );
496 painter->rotate( -label->
getAlpha() * 180 / M_PI );
500 painter->setBrush( QColor( 255, 0, 0, 100 ) );
501 painter->setPen( QColor( 255, 0, 0, 150 ) );
505 painter->setBrush( QColor( 0, 255, 0, 100 ) );
506 painter->setPen( QColor( 0, 255, 0, 150 ) );
509 painter->drawRect( rect );
518 QgsTextRenderer::Component component;
519 component.dpiRatio = dpiRatio;
520 component.origin = outPt;
521 component.rotation = label->
getAlpha();
526 QPointF centerPt( outPt );
530 double xc = outPt2.
x() - outPt.x();
531 double yc = outPt2.
y() - outPt.y();
533 double angle = -component.rotation;
534 double xd = xc * std::cos(
angle ) - yc * std::sin(
angle );
535 double yd = xc * std::sin(
angle ) + yc * std::cos(
angle );
537 centerPt.setX( centerPt.x() + xd );
538 centerPt.setY( centerPt.y() + yd );
540 component.center = centerPt;
546 component.size = QSizeF( labelWidthPx, labelHeightPx );
571 bool prependSymb =
false;
598 symb = symb + QStringLiteral(
"\n" );
603 symb = QStringLiteral(
"\n" ) + symb;
629 QgsTextRenderer::Component component;
630 component.origin = outPt;
631 component.rotation = label->
getAlpha();
638 for (
const QString &line : multiLineList )
646 QgsTextRenderer::drawTextInternal( drawType, context, tmpLyr.
format(), component, document, labelfm,
Flags mFlags
Flags altering drawing and registration of features.
QgsCoordinateTransform ct
const QMap< QgsPalLayerSettings::DataDefinedProperties, QVariant > & dataDefinedValues() const
Gets data-defined values.
double getY(int i=0) const
Returns the down-left y coordinate.
virtual void stopRender(QgsRenderContext &context)
To be called after rendering is complete.
QString text(int partId) const
Returns the text component corresponding to a specified label part.
double convertToPainterUnits(double size, QgsUnitTypes::RenderUnit unit, const QgsMapUnitScale &scale=QgsMapUnitScale()) const
Converts a size from the specified units to painter units (pixels).
const QgsMapToPixel & mapToPixel() const
Returns the context's map to pixel transform, which transforms between map coordinates and device coo...
TextPart
Components of text.
void registerFeature(const QgsFeature &f, QgsRenderContext &context, QgsLabelFeature **labelFeature=nullptr, QgsGeometry obstacleGeometry=QgsGeometry(), const QgsSymbol *symbol=nullptr)
Register a feature for labeling.
void setFont(const QFont &font)
Sets the font used for rendering text.
QString layerId() const
Returns ID of associated layer, or empty string if no layer is associated with the provider.
QgsExpressionContext & expressionContext()
Gets the expression context.
QgsExpressionContextScope * popScope()
Removes the last scope from the expression context and return it.
bool enabled() const
Returns whether the background is enabled.
QgsFeatureRenderer * mRenderer
QgsTextShadowSettings & shadow()
Returns a reference to the text drop shadow settings.
QList< QgsLabelFeature * > labelFeatures(QgsRenderContext &context) override
Returns list of label features (they are owned by the provider and thus deleted on its destruction)
Point geometry type, with support for z-dimension and m-values.
QFontMetricsF * labelFontMetrics()
Metrics of the font for rendering.
@ Background
Background shape.
#define QgsDebugMsgLevel(str, level)
@ ShadowBuffer
Draw shadow under buffer.
QgsTextBufferSettings & buffer()
Returns a reference to the text buffer settings.
@ AlignCenter
Center align.
void drawLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw this label at the position determined by the labeling engine.
@ DrawLabels
Whether the labels should be rendered.
const QgsCoordinateReferenceSystem & crs
QString mName
Name of the layer.
LabelPosition is a candidate feature label position.
QgsTextCharacterFormat characterFormat(int partId) const
Returns the character format corresponding to the specified label part.
QgsExpressionContextScope * lastScope()
Returns the last scope added to the context.
UpsideDownLabels upsidedownLabels
Controls whether upside down labels are displayed and how they are handled.
void setOriginalValueVariable(const QVariant &value)
Sets the original value variable value for the context.
Container of fields for a vector layer.
QgsTextBackgroundSettings & background()
Returns a reference to the text background settings.
const QgsLabelObstacleSettings & obstacleSettings() const
Returns the label obstacle settings.
QgsAbstractLabelProvider * provider() const
Returns pointer to the associated provider.
Stores information relating to individual character formatting.
Contains information about the context of a rendering operation.
QPointF toQPointF() const
Converts a point to a QPointF.
Quadrant getQuadrant() const
QgsFeatureRequest & setSubsetOfAttributes(const QgsAttributeList &attrs)
Set a subset of attributes that will be fetched.
Abstract base class for all rendered symbols.
QgsPointXY toMapCoordinates(int x, int y) const
Transform device coordinates to map (world) coordinates.
@ Line
Arranges candidates parallel to a generalised line representing the feature or parallel to a polygon'...
LabelPosition * nextPart() const
Returns the next part of this label position (i.e.
const QgsRectangle & extent() const
When rendering a map layer, calling this method returns the "clipping" extent for the layer (in the l...
Class that adds extra information to QgsLabelFeature for text labels.
bool reverseDirectionSymbol() const
Returns true if direction symbols should be reversed.
A rectangle specified with double values.
FeaturePart * getFeaturePart() const
Returns the feature corresponding to this labelposition.
std::unique_ptr< QgsAbstractFeatureSource > mSource
Layer's feature source.
bool enabled() const
Returns whether the shadow is enabled.
virtual void stopRender(QgsRenderContext &context)
Must be called when a render cycle has finished, to allow the renderer to clean up.
QString mProviderId
Associated provider ID (one layer may have multiple providers, e.g. in rule-based labeling)
QString leftDirectionSymbol() const
Returns the string to use for left direction arrows.
virtual QgsPoint vertexAt(QgsVertexId id) const =0
Returns the point corresponding to a specified vertex id.
Layer * layer()
Returns the layer that feature belongs to.
const QgsPalLayerSettings & settings() const
Returns the layer's settings.
QgsFeatureRequest & setFilterRect(const QgsRectangle &rectangle)
Sets the rectangle from which features will be taken.
bool displayAll
If true, all features will be labelled even when overlaps occur.
const QgsLabelingEngineSettings & engineSettings() const
Gets associated labeling engine settings.
QgsFields mFields
Layer's fields.
QgsCoordinateTransform coordinateTransform() const
Returns the current coordinate transform for the context.
Container for all settings relating to text rendering.
void setColor(const QColor &color)
Sets the color that text will be rendered in.
This class wraps a request for features to a vector layer (or directly its vector data provider).
QgsPalLayerSettings::UpsideDownLabels mUpsidedownLabels
How to handle labels that would be upside down.
bool hasFixedPosition() const
Whether the label should use a fixed position instead of being automatically placed.
@ Curved
Arranges candidates following the curvature of a line feature. Applies to line layers only.
QString mLayerId
Associated layer's ID, if applicable.
Custom exception class for Coordinate Reference System related exceptions.
bool mergeLines() const
Returns true if connected line features with identical label text should be merged prior to generatin...
@ MergeConnectedLines
Whether adjacent lines (with the same label text) should be merged.
void stopRender(QgsRenderContext &context) override
To be called after rendering is complete.
The QgsAbstractLabelProvider class is an interface class.
const QgsMaskIdProvider * maskIdProvider() const
Returns the mask id provider attached to the context.
bool labelAllParts() const
Returns true if all parts of the feature should be labeled.
@ CentroidMustBeInside
Whether location of centroid must be inside of polygons.
void stopRender(QgsRenderContext &context)
Finalises the label settings after use.
QString wrapChar
Wrapping character string.
Stores a fragment of text along with formatting overrides to be used when rendering the fragment.
QList< QgsSymbol * > QgsSymbolList
A marker symbol type, for rendering Point and MultiPoint geometries.
@ ShadowLowest
Draw shadow below all text components.
int autoWrapLength
If non-zero, indicates that label text should be automatically wrapped to (ideally) the specified num...
bool testFlag(Flag f) const
Test whether a particular flag is enabled.
MultiLineAlign multilineAlign
Horizontal alignment of multi-line labels.
virtual QgsSymbolList originalSymbolsForFeature(const QgsFeature &feature, QgsRenderContext &context) const
Equivalent of originalSymbolsForFeature() call extended to support renderers that may use more symbol...
const QgsTextFormat & format() const
Returns the label text formatting settings, e.g., font settings, buffer settings, etc.
bool allFeaturePartsLabeled
true if all parts of associated feature were labeled
@ CalloutDraw
Show callout.
bool drawLabels
Whether to draw labels for this layer.
void setFormat(const QgsTextFormat &format)
Sets the label text formatting settings, e.g., font settings, buffer settings, etc.
@ AlignJustify
Justify align.
QColor unplacedLabelColor() const
Returns the color to use when rendering unplaced labels.
void startRender(QgsRenderContext &context)
Prepares the label settings for rendering.
bool allowHtmlFormatting() const
Returns true if text should be treated as a HTML document and HTML tags should be used for formatting...
static QStringList splitToLines(const QString &text, const QString &wrapCharacter, int autoWrapLength=0, bool useMaxLineLengthWhenAutoWrapping=true)
Splits a text string to a list of separate lines, using a specified wrap character (wrapCharacter).
QString rightDirectionSymbol() const
Returns the string to use for right direction arrows.
virtual DrawOrder drawOrder() const
Returns the desired drawing order (stacking) to use while rendering this callout.
QFont definedFont()
Font to be used for rendering.
const QgsLabelLineSettings & lineSettings() const
Returns the label line settings, which contain settings related to how the label engine places and fo...
QString id() const
Returns the layer's unique ID, which is used to access this layer from QgsProject.
void setShadowPlacement(QgsTextShadowSettings::ShadowPlacement placement)
Sets the placement for the drop shadow.
Multi polygon geometry collection.
virtual int nCoordinates() const
Returns the number of nodes contained in the geometry.
Struct for storing maximum and minimum scales for measurements in map units.
void drawUnplacedLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw an unplaced label.
ObstacleType type() const
Returns how features act as obstacles for labels.
const QgsLabelingEngine * mEngine
Associated labeling engine.
const QgsAbstractGeometry * constGet() const SIP_HOLDGIL
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
QString providerId() const
Returns provider ID - useful in case there is more than one label provider within a layer (e....
ShapeType type() const
Returns the type of background shape (e.g., square, ellipse, SVG).
This class represents a coordinate reference system (CRS).
QgsPointXY transform(const QgsPointXY &p) const
Transform the point from map (world) coordinates to device coordinates.
@ ShadowShape
Draw shadow under background shape.
Single scope for storing variables and functions for use within a QgsExpressionContext.
Represents a block of text consisting of one or more QgsTextFragment objects.
void appendScope(QgsExpressionContextScope *scope)
Appends a scope to the end of the context.
A class to represent a 2D point.
virtual void startRender(QgsRenderContext &context)
To be called before rendering of labels begins.
@ DrawAllLabels
Whether all features will be labelled even though overlaps occur.
bool prepare(QgsRenderContext &context, QSet< QString > &attributeNames, const QgsFields &fields, const QgsMapSettings &mapSettings, const QgsCoordinateReferenceSystem &crs)
Prepare for registration of features.
void init()
initialization method - called from constructors
void transformInPlace(double &x, double &y) const
Transform device coordinates to map coordinates.
int priority
Label priority.
bool enabled() const
Returns whether the buffer is enabled.
@ SymbolLeftRight
Place direction symbols on left/right of label.
static QgsExpressionContextScope * updateSymbolScope(const QgsSymbol *symbol, QgsExpressionContextScope *symbolScope=nullptr)
Updates a symbol scope related to a QgsSymbol to an expression context.
const QgsMapSettings & mapSettings() const
Gets associated map settings.
GeometryType
The geometry types are used to group QgsWkbTypes::Type in a coarse way.
GEOSGeometry * geometry() const
Gets access to the associated geometry.
bool nextFeature(QgsFeature &f)
bool conflictsWithObstacle() const
Returns whether the position is marked as conflicting with an obstacle feature.
void drawLabelPrivate(pal::LabelPosition *label, QgsRenderContext &context, QgsPalLayerSettings &tmpLyr, QgsTextRenderer::TextPart drawType, double dpiRatio=1.0) const
Internal label drawing method.
As part of the API refactoring and improvements which landed in the Processing API was substantially reworked from the x version This was done in order to allow much of the underlying Processing framework to be ported into c
A geometry is the spatial representation of a feature.
bool valueAsBool(int key, const QgsExpressionContext &context, bool defaultValue=false, bool *ok=nullptr) const
Calculates the current value of the property with the specified key and interprets it as an boolean.
Perform transforms between map coordinates and device coordinates.
void drawLabelBackground(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw the background for the specified label.
void startRender(QgsRenderContext &context) override
To be called before rendering of labels begins.
@ SymbolAbove
Place direction symbols on above label.
QgsLabelingResults * results() const
For internal use by the providers.
Represents a vector layer which manages a vector based data sets.
bool hasGeometry() const
Returns true if the feature has an associated geometry.
Base class for all map layer types.
Represents a document consisting of one or more QgsTextBlock objects.
void render(QgsRenderContext &context, QRectF rect, const double angle, const QgsGeometry &anchor, QgsCalloutContext &calloutContext)
Renders the callout onto the specified render context.
@ ShadowText
Draw shadow under text.
double getX(int i=0) const
Returns the down-left x coordinate.
Utility class for identifying a unique vertex within a geometry.
@ SymbolBelow
Place direction symbols on below label.
QgsPalLayerSettings mSettings
Layer's labeling configuration.
void append(const QgsTextBlock &block)
Appends a block to the document.
Contains additional contextual information about the context in which a callout is being rendered.
@ DrawLabelRectOnly
Whether to only draw the label rect and not the actual label text (used for unit tests)
QgsTextDocument document() const
Returns the document for the label.
QList< QgsLabelFeature * > mLabels
List of generated.
virtual void registerFeature(const QgsFeature &feature, QgsRenderContext &context, const QgsGeometry &obstacleGeometry=QgsGeometry(), const QgsSymbol *symbol=nullptr)
Register a feature for labeling as one or more QgsLabelFeature objects stored into mLabels.
QgsCallout * callout() const
Returns the label callout renderer, responsible for drawing label callouts.
@ Label
Label-specific draw mode.
QgsMapLayer * layer() const
Returns the associated layer, or nullptr if no layer is associated with the provider.
bool useMaxLineLengthForAutoWrap
If true, indicates that when auto wrapping label text the autoWrapLength length indicates the maximum...
QFont font() const
Returns the font used for rendering text.
void setSizeUnit(QgsUnitTypes::RenderUnit unit)
Sets the units for the size of rendered text.
static QgsGeometry getPointObstacleGeometry(QgsFeature &fet, QgsRenderContext &context, const QgsSymbolList &symbols)
Returns the geometry for a point feature which should be used as an obstacle for labels.
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
DirectionSymbolPlacement directionSymbolPlacement() const
Returns the placement for direction symbols.
QgsWkbTypes::GeometryType mLayerGeometryType
Geometry type of layer.
The QgsLabelFeature class describes a feature that should be used within the labeling engine.
virtual bool prepare(QgsRenderContext &context, QSet< QString > &attributeNames)
Prepare for registration of features.
@ Buffer
Buffer component.
QgsLabelObstacleSettings::ObstacleType mObstacleType
Type of the obstacle of feature geometries.
double getAlpha() const
Returns the angle to rotate text (in rad).
QgsVectorLayerLabelProvider(QgsVectorLayer *layer, const QString &providerId, bool withFeatureLoop, const QgsPalLayerSettings *settings, const QString &layerName=QString())
Convenience constructor to initialize the provider from given vector layer.
QPainter * painter()
Returns the destination QPainter for the render operation.
void setSize(double size)
Sets the size for rendered text.
QgsFeatureId featureId() const
Returns the unique ID of the feature.
bool addDirectionSymbol() const
Returns true if '<' or '>' (or custom strings set via leftDirectionSymbol and rightDirectionSymbol) w...
@ ShapeMarkerSymbol
Marker symbol.
static std::unique_ptr< QgsAbstractGeometry > fromGeos(const GEOSGeometry *geos)
Create a geometry from a GEOSGeometry.
The QgsMapSettings class contains configuration for rendering of the map.
QgsPropertyCollection & dataDefinedProperties()
Returns a reference to the label's property collection, used for data defined overrides.
QgsTextShadowSettings::ShadowPlacement shadowPlacement() const
Returns the placement for the drop shadow.
bool isActive(int key) const override
Returns true if the collection contains an active property with the specified key.
QgsLabelFeature * feature()
Returns the parent feature.
~QgsVectorLayerLabelProvider() override
virtual void startRender(QgsRenderContext &context, const QgsFields &fields)
Must be called when a new render cycle is started.
QgsWkbTypes::GeometryType type
@ OrderBelowAllLabels
Render callouts below all labels.
Wrapper for iterator of features from vector data provider or vector layer.
void setCurrentMaskId(int id)
Stores a mask id as the "current" one.
@ OrderBelowIndividualLabels
Render callouts below their individual associated labels, some callouts may be drawn over other label...
double ANALYSIS_EXPORT angle(QgsPoint *p1, QgsPoint *p2, QgsPoint *p3, QgsPoint *p4)
Calculates the angle between two segments (in 2 dimension, z-values are ignored)
void setMapRotation(double degrees, double cx, double cy)
Set map rotation in degrees (clockwise)
QgsPalLayerSettings::Placement mPlacement
Placement strategy.
@ RenderMapUnits
Map units.
double mPriority
Default priority of labels.
QString labelText() const
Text of the label.
bool enabled() const
Returns true if the the callout is enabled.
bool centroidInside
true if centroid positioned labels must be placed inside their corresponding feature polygon,...
HAlignment
Horizontal alignment.
QgsCoordinateReferenceSystem mCrs
Layer's CRS.
void setFeature(const QgsFeature &feature)
Convenience function for setting a feature for the context.