QGIS API Documentation 3.27.0-Master (f261cc1f8b)
layer.h
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1/*
2 * libpal - Automated Placement of Labels Library
3 *
4 * Copyright (C) 2008 Maxence Laurent, MIS-TIC, HEIG-VD
5 * University of Applied Sciences, Western Switzerland
6 * http://www.hes-so.ch
7 *
8 * Contact:
9 * maxence.laurent <at> heig-vd <dot> ch
10 * or
11 * eric.taillard <at> heig-vd <dot> ch
12 *
13 * This file is part of libpal.
14 *
15 * libpal is free software: you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation, either version 3 of the License, or
18 * (at your option) any later version.
19 *
20 * libpal is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with libpal. If not, see <http://www.gnu.org/licenses/>.
27 *
28 */
29
30#ifndef PAL_LAYER_H_
31#define PAL_LAYER_H_
32
33#define SIP_NO_FILE
34
35
36#include "qgis_core.h"
37#include "pal.h" // for LineArrangementFlags enum
38#include "qgsgeos.h"
41#include <QMutex>
42#include <QLinkedList>
43#include <QHash>
44#include <fstream>
45
46class QgsLabelFeature;
47
48namespace pal
49{
50
51 class FeaturePart;
52
53 class Pal;
54 class LabelInfo;
55
62 class CORE_EXPORT Layer
63 {
64 friend class Pal;
65 friend class FeaturePart;
66
67 friend class Problem;
68
69 friend class LabelPosition;
70
71 public:
72
84 Layer( QgsAbstractLabelProvider *provider, const QString &name, Qgis::LabelPlacement arrangement, double defaultPriority, bool active, bool toLabel, Pal *pal );
85
86 virtual ~Layer();
87
91 int featureCount() { return mHashtable.size(); }
92
97 std::size_t maximumPointLabelCandidates() const
98 {
99 // when an extreme number of features exist in the layer, we limit the number of candidates
100 // to avoid the engine processing endlessly...
101 const int size = mHashtable.size();
102 if ( size > 1000 )
103 return static_cast< std::size_t >( mPal->globalCandidatesLimitPoint() > 0 ? std::min( mPal->globalCandidatesLimitPoint(), 4 ) : 4 );
104 else if ( size > 500 )
105 return static_cast< std::size_t >( mPal->globalCandidatesLimitPoint() > 0 ? std::min( mPal->globalCandidatesLimitPoint(), 6 ) : 6 );
106 else if ( size > 200 )
107 return static_cast< std::size_t >( mPal->globalCandidatesLimitPoint() > 0 ? std::min( mPal->globalCandidatesLimitPoint(), 8 ) : 8 );
108 else if ( size > 100 )
109 return static_cast< std::size_t >( mPal->globalCandidatesLimitPoint() > 0 ? std::min( mPal->globalCandidatesLimitPoint(), 12 ) : 12 );
110 else
111 return static_cast< std::size_t >( std::max( mPal->globalCandidatesLimitPoint(), 0 ) );
112 }
113
118 std::size_t maximumLineLabelCandidates() const
119 {
120 // when an extreme number of features exist in the layer, we limit the number of candidates
121 // to avoid the engine processing endlessly...
122 const int size = mHashtable.size();
123 if ( size > 1000 )
124 return static_cast< std::size_t >( mPal->globalCandidatesLimitLine() > 0 ? std::min( mPal->globalCandidatesLimitLine(), 5 ) : 5 );
125 else if ( size > 500 )
126 return static_cast< std::size_t >( mPal->globalCandidatesLimitLine() > 0 ? std::min( mPal->globalCandidatesLimitLine(), 10 ) : 10 );
127 else if ( size > 200 )
128 return static_cast< std::size_t >( mPal->globalCandidatesLimitLine() > 0 ? std::min( mPal->globalCandidatesLimitLine(), 20 ) : 20 );
129 else if ( size > 100 )
130 return static_cast< std::size_t >( mPal->globalCandidatesLimitLine() > 0 ? std::min( mPal->globalCandidatesLimitLine(), 40 ) : 40 );
131 else
132 return static_cast< std::size_t >( std::max( mPal->globalCandidatesLimitLine(), 0 ) );
133 }
134
140 {
141 // when an extreme number of features exist in the layer, we limit the number of candidates
142 // to avoid the engine processing endlessly...
143 const int size = mHashtable.size();
144 if ( size > 1000 )
145 return static_cast< std::size_t >( mPal->globalCandidatesLimitPolygon() > 0 ? std::min( mPal->globalCandidatesLimitPolygon(), 5 ) : 5 );
146 else if ( size > 500 )
147 return static_cast< std::size_t >( mPal->globalCandidatesLimitPolygon() > 0 ? std::min( mPal->globalCandidatesLimitPolygon(), 15 ) : 15 );
148 else if ( size > 200 )
149 return static_cast< std::size_t >( mPal->globalCandidatesLimitPolygon() > 0 ? std::min( mPal->globalCandidatesLimitPolygon(), 20 ) : 20 );
150 else if ( size > 100 )
151 return static_cast< std::size_t >( mPal->globalCandidatesLimitPolygon() > 0 ? std::min( mPal->globalCandidatesLimitPolygon(), 25 ) : 25 );
152 else
153 return static_cast< std::size_t >( std::max( mPal->globalCandidatesLimitPolygon(), 0 ) );
154 }
155
157 QgsAbstractLabelProvider *provider() const { return mProvider; }
158
162 QString name() const { return mName; }
163
168 Qgis::LabelPlacement arrangement() const { return mArrangement; }
169
173 bool isCurved() const { return mArrangement == Qgis::LabelPlacement::Curved || mArrangement == Qgis::LabelPlacement::PerimeterCurved; }
174
180 void setArrangement( Qgis::LabelPlacement arrangement ) { mArrangement = arrangement; }
181
192 void setActive( bool active ) { mActive = active; }
193
198 bool active() const { return mActive; }
199
207 void setLabelLayer( bool toLabel ) { mLabelLayer = toLabel; }
208
213 bool labelLayer() const { return mLabelLayer; }
214
220 QgsLabelObstacleSettings::ObstacleType obstacleType() const { return mObstacleType; }
221
228 void setObstacleType( QgsLabelObstacleSettings::ObstacleType obstacleType ) { mObstacleType = obstacleType; }
229
236 void setPriority( double priority );
237
243 double priority() const { return mDefaultPriority; }
244
250 void setMergeConnectedLines( bool merge ) { mMergeLines = merge; }
251
256 bool mergeConnectedLines() const { return mMergeLines; }
257
263 void setUpsidedownLabels( Qgis::UpsideDownLabelHandling ud ) { mUpsidedownLabels = ud; }
264
269 Qgis::UpsideDownLabelHandling upsidedownLabels() const { return mUpsidedownLabels; }
270
278 void setCentroidInside( bool forceInside ) { mCentroidInside = forceInside; }
279
285 bool centroidInside() const { return mCentroidInside; }
286
296 bool registerFeature( QgsLabelFeature *label );
297
299 void joinConnectedFeatures();
300
306 int connectedFeatureId( QgsFeatureId featureId ) const;
307
309 void chopFeaturesAtRepeatDistance();
310
311 protected:
313 QString mName;
314
316 std::deque< std::unique_ptr< FeaturePart > > mFeatureParts;
317
319 QList<FeaturePart *> mObstacleParts;
320
321 std::vector< geos::unique_ptr > mGeosObstacleGeometries;
322
323 Pal *mPal = nullptr;
324
326
330 bool mCentroidInside = false;
331
334
335 bool mMergeLines = false;
336
337 Qgis::UpsideDownLabelHandling mUpsidedownLabels = Qgis::UpsideDownLabelHandling::FlipUpsideDownLabels;
338
340 QHash< QgsFeatureId, QgsLabelFeature *> mHashtable;
341
342 QHash< QString, QVector<FeaturePart *> > mConnectedHashtable;
343 QHash< QgsFeatureId, int > mConnectedFeaturesIds;
344
345 QMutex mMutex;
346
348 void addFeaturePart( std::unique_ptr< FeaturePart > fpart, const QString &labelText = QString() );
349
351 void addObstaclePart( FeaturePart *fpart );
352
353 };
354
355} // end namespace pal
356
357
358#endif
LabelPlacement
Placement modes which determine how label candidates are generated for a feature.
Definition: qgis.h:561
@ Curved
Arranges candidates following the curvature of a line feature. Applies to line layers only.
@ PerimeterCurved
Arranges candidates following the curvature of a polygon's boundary. Applies to polygon layers only.
UpsideDownLabelHandling
Handling techniques for upside down labels.
Definition: qgis.h:643
The QgsAbstractLabelProvider class is an interface class.
The QgsLabelFeature class describes a feature that should be used within the labeling engine.
ObstacleType
Valid obstacle types, which affect how features within the layer will act as obstacles for labels.
Main class to handle feature.
Definition: feature.h:65
pal labeling engine
LabelPosition is a candidate feature label position.
Definition: labelposition.h:56
A set of features which influence the labeling process.
Definition: layer.h:63
QMutex mMutex
Definition: layer.h:345
void setUpsidedownLabels(Qgis::UpsideDownLabelHandling ud)
Sets how upside down labels will be handled within the layer.
Definition: layer.h:263
QHash< QString, QVector< FeaturePart * > > mConnectedHashtable
Definition: layer.h:342
std::deque< std::unique_ptr< FeaturePart > > mFeatureParts
List of feature parts.
Definition: layer.h:316
QList< FeaturePart * > mObstacleParts
List of obstacle parts.
Definition: layer.h:319
double mDefaultPriority
Definition: layer.h:325
QString name() const
Returns the layer's name.
Definition: layer.h:162
bool mLabelLayer
Definition: layer.h:329
QgsAbstractLabelProvider * provider() const
Returns pointer to the associated provider.
Definition: layer.h:157
std::size_t maximumPolygonLabelCandidates() const
Returns the maximum number of polygon label candidates to generate for features in this layer.
Definition: layer.h:139
bool active() const
Returns whether the layer is currently active.
Definition: layer.h:198
void setObstacleType(QgsLabelObstacleSettings::ObstacleType obstacleType)
Sets the obstacle type, which controls how features within the layer act as obstacles for labels.
Definition: layer.h:228
QgsAbstractLabelProvider * mProvider
Definition: layer.h:312
Qgis::LabelPlacement arrangement() const
Returns the layer's arrangement policy.
Definition: layer.h:168
std::size_t maximumPointLabelCandidates() const
Returns the maximum number of point label candidates to generate for features in this layer.
Definition: layer.h:97
bool mergeConnectedLines() const
Returns whether connected lines will be merged before labeling.
Definition: layer.h:256
void setMergeConnectedLines(bool merge)
Sets whether connected lines should be merged before labeling.
Definition: layer.h:250
void setActive(bool active)
Sets whether the layer is currently active.
Definition: layer.h:192
QHash< QgsFeatureId, int > mConnectedFeaturesIds
Definition: layer.h:343
Qgis::UpsideDownLabelHandling upsidedownLabels() const
Returns how upside down labels are handled within the layer.
Definition: layer.h:269
void setArrangement(Qgis::LabelPlacement arrangement)
Sets the layer's arrangement policy.
Definition: layer.h:180
QHash< QgsFeatureId, QgsLabelFeature * > mHashtable
Lookup table of label features (owned by the label feature provider that created them)
Definition: layer.h:340
void setLabelLayer(bool toLabel)
Sets whether the layer will be labeled.
Definition: layer.h:207
std::vector< geos::unique_ptr > mGeosObstacleGeometries
Definition: layer.h:321
int featureCount()
Returns the number of features in layer.
Definition: layer.h:91
QString mName
Definition: layer.h:313
Qgis::LabelPlacement mArrangement
Optional flags used for some placement methods.
Definition: layer.h:333
bool labelLayer() const
Returns whether the layer will be labeled or not.
Definition: layer.h:213
bool centroidInside() const
Returns whether labels placed at the centroid of features within the layer are forced to be placed in...
Definition: layer.h:285
bool isCurved() const
Returns true if the layer has curved labels.
Definition: layer.h:173
void setCentroidInside(bool forceInside)
Sets whether labels placed at the centroid of features within the layer are forced to be placed insid...
Definition: layer.h:278
QgsLabelObstacleSettings::ObstacleType obstacleType() const
Returns the obstacle type, which controls how features within the layer act as obstacles for labels.
Definition: layer.h:220
double priority() const
Returns the layer's priority, between 0 and 1.
Definition: layer.h:243
bool mActive
Definition: layer.h:328
std::size_t maximumLineLabelCandidates() const
Returns the maximum number of line label candidates to generate for features in this layer.
Definition: layer.h:118
Main Pal labeling class.
Definition: pal.h:80
Representation of a labeling problem.
Definition: problem.h:73
qint64 QgsFeatureId
64 bit feature ids negative numbers are used for uncommitted/newly added features
Definition: qgsfeatureid.h:28