QGIS API Documentation  3.26.3-Buenos Aires (65e4edfdad)
qgslabelsink.cpp
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1 /***************************************************************************
2  qgslabelsink.cpp
3  ---------------------
4  begin : January 2014
5  copyright : (C) 2014 by Marco Hugentobler
6  email : marco at sourcepole dot ch
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #include "qgslabelsink.h"
19 #include "qgspallabeling.h"
20 #include "qgsmapsettings.h"
21 #include "qgslogger.h"
22 
23 QgsLabelSinkProvider::QgsLabelSinkProvider( QgsVectorLayer *layer, const QString &providerId, QgsLabelSink *sink, const QgsPalLayerSettings *settings )
24  : QgsVectorLayerLabelProvider( layer, providerId, false, settings )
25  , mLabelSink( sink )
26 {
27 }
28 
30 {
31  Q_ASSERT( mLabelSink );
32  mLabelSink->drawLabel( layerId(), context, label, mSettings );
33 }
34 
36 {
37  Q_ASSERT( mLabelSink );
38  mLabelSink->drawUnplacedLabel( layerId(), context, label, mSettings );
39 }
40 
42  : QgsRuleBasedLabelProvider( rules, layer, false )
43  , mLabelSink( sink )
44 {
45  mRules->rootRule()->createSubProviders( layer, mSubProviders, this );
46 }
47 
49 {
50  mRules->rootRule()->createSubProviders( layer, mSubProviders, this );
51 }
52 
53 QgsVectorLayerLabelProvider *QgsRuleBasedLabelSinkProvider::createProvider( QgsVectorLayer *layer, const QString &providerId, bool withFeatureLoop, const QgsPalLayerSettings *settings )
54 {
55  Q_UNUSED( withFeatureLoop )
56  return new QgsLabelSinkProvider( layer, providerId, mLabelSink, settings );
57 }
58 
60 {
61  Q_ASSERT( mLabelSink );
62  mLabelSink->drawLabel( layerId(), context, label, mSettings );
63 }
64 
66 {
67  Q_ASSERT( mLabelSink );
68  mLabelSink->drawUnplacedLabel( layerId(), context, label, mSettings );
69 }
qgspallabeling.h
QgsAbstractLabelProvider::layerId
QString layerId() const
Returns ID of associated layer, or empty string if no layer is associated with the provider.
Definition: qgslabelingengine.h:131
QgsPalLayerSettings
Contains settings for how a map layer will be labeled.
Definition: qgspallabeling.h:86
QgsRuleBasedLabelProvider::mRules
std::unique_ptr< QgsRuleBasedLabeling > mRules
owned copy
Definition: qgsrulebasedlabeling.h:429
pal::LabelPosition
LabelPosition is a candidate feature label position.
Definition: labelposition.h:55
QgsLabelSink
Abstract base class that can be used to intercept rendered labels from a labeling / rendering job.
Definition: qgslabelsink.h:37
QgsRenderContext
Contains information about the context of a rendering operation.
Definition: qgsrendercontext.h:59
qgsmapsettings.h
QgsRuleBasedLabelSinkProvider::QgsRuleBasedLabelSinkProvider
QgsRuleBasedLabelSinkProvider(const QgsRuleBasedLabeling &rules, QgsVectorLayer *layer, QgsLabelSink *sink)
Creates a rule based label sink provider which will draw/register labels in sink.
Definition: qgslabelsink.cpp:41
QgsVectorLayerLabelProvider
The QgsVectorLayerLabelProvider class implements a label provider for vector layers....
Definition: qgsvectorlayerlabelprovider.h:41
QgsRuleBasedLabeling
Rule based labeling for a vector layer.
Definition: qgsrulebasedlabeling.h:42
QgsVectorLayerLabelProvider::settings
const QgsPalLayerSettings & settings() const
Returns the layer's settings.
Definition: qgsvectorlayerlabelprovider.cpp:682
QgsRuleBasedLabelProvider::mSubProviders
QgsRuleBasedLabeling::RuleToProviderMap mSubProviders
label providers are owned by labeling engine
Definition: qgsrulebasedlabeling.h:431
qgslabelsink.h
QgsRuleBasedLabelSinkProvider::drawLabel
void drawLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw this label at the position determined by the labeling engine.
Definition: qgslabelsink.cpp:59
QgsLabelSinkProvider::QgsLabelSinkProvider
QgsLabelSinkProvider(QgsVectorLayer *layer, const QString &providerId, QgsLabelSink *sink, const QgsPalLayerSettings *settings)
Creates a rule based label sink provider which will draw/register labels in sink.
Definition: qgslabelsink.cpp:23
QgsRuleBasedLabelSinkProvider::reinit
Q_DECL_DEPRECATED void reinit(QgsVectorLayer *layer)
Reinitialize the subproviders with QgsLabelSinkProviders.
Definition: qgslabelsink.cpp:48
QgsAbstractLabelProvider::providerId
QString providerId() const
Returns provider ID - useful in case there is more than one label provider within a layer (e....
Definition: qgslabelingengine.h:145
QgsLabelSink::drawLabel
virtual void drawLabel(const QString &layerId, QgsRenderContext &context, pal::LabelPosition *label, const QgsPalLayerSettings &settings)=0
The drawLabel method is called for each label that is being drawn.
QgsLabelSinkProvider::drawLabel
void drawLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw this label at the position determined by the labeling engine.
Definition: qgslabelsink.cpp:29
QgsLabelSinkProvider::drawUnplacedLabel
void drawUnplacedLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw an unplaced label.
Definition: qgslabelsink.cpp:35
QgsVectorLayer
Represents a vector layer which manages a vector based data sets.
Definition: qgsvectorlayer.h:391
QgsLabelSinkProvider
Implements a derived label provider for use with QgsLabelSink.
Definition: qgslabelsink.h:74
QgsVectorLayerLabelProvider::mSettings
QgsPalLayerSettings mSettings
Layer's labeling configuration.
Definition: qgsvectorlayerlabelprovider.h:130
QgsAbstractLabelProvider::layer
QgsMapLayer * layer() const
Returns the associated layer, or nullptr if no layer is associated with the provider.
Definition: qgslabelingengine.h:138
QgsRuleBasedLabelSinkProvider::drawUnplacedLabel
void drawUnplacedLabel(QgsRenderContext &context, pal::LabelPosition *label) const override
Draw an unplaced label.
Definition: qgslabelsink.cpp:65
qgslogger.h
QgsRuleBasedLabelSinkProvider::createProvider
QgsVectorLayerLabelProvider * createProvider(QgsVectorLayer *layer, const QString &providerId, bool withFeatureLoop, const QgsPalLayerSettings *settings) override
Creates a QgsRuleBasedLabelSinkProvider.
Definition: qgslabelsink.cpp:53
QgsRuleBasedLabelProvider
Label provider for rule based labeling.
Definition: qgsrulebasedlabeling.h:410
QgsLabelSink::drawUnplacedLabel
virtual void drawUnplacedLabel(const QString &layerId, QgsRenderContext &context, pal::LabelPosition *label, const QgsPalLayerSettings &settings)
The drawLabel method is called for each unplaced label.
Definition: qgslabelsink.h:57