QGIS API Documentation  3.18.1-Zürich (202f1bf7e5)
feature.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 FEATURE_H
31 #define FEATURE_H
32 
33 #define SIP_NO_FILE
34 
35 
36 #include "qgis_core.h"
37 #include "pointset.h"
38 #include "labelposition.h" // for LabelPosition enum
39 #include "qgslabelfeature.h"
40 #include <iostream>
41 #include <fstream>
42 #include <cmath>
43 #include <QString>
44 
52 namespace pal
53 {
55  class CORE_EXPORT LabelInfo
56  {
57  public:
59  {
60  double width;
61  };
62 
63  LabelInfo( int num, double height, double maxinangle = 20.0, double maxoutangle = -20.0 )
64  {
65  max_char_angle_inside = maxinangle;
66  // outside angle should be negative
67  max_char_angle_outside = maxoutangle > 0 ? -maxoutangle : maxoutangle;
68  label_height = height;
69  char_num = num;
70  char_info = new CharacterInfo[num];
71  }
72  ~LabelInfo() { delete [] char_info; }
73 
75  LabelInfo( const LabelInfo &rh ) = delete;
77  LabelInfo &operator=( const LabelInfo &rh ) = delete;
78 
81  double label_height;
82  int char_num;
83  CharacterInfo *char_info = nullptr;
84 
85  };
86 
87  class LabelPosition;
88  class FeaturePart;
89 
96  class CORE_EXPORT FeaturePart : public PointSet
97  {
98 
99  public:
100 
106  FeaturePart( QgsLabelFeature *lf, const GEOSGeometry *geom );
107 
108  FeaturePart( const FeaturePart &other );
109 
113  ~FeaturePart() override;
114 
118  QgsLabelFeature *feature() { return mLF; }
119 
123  Layer *layer();
124 
128  QgsFeatureId featureId() const;
129 
133  std::size_t maximumPointCandidates() const;
134 
138  std::size_t maximumLineCandidates() const;
139 
143  std::size_t maximumPolygonCandidates() const;
144 
148  std::vector<std::unique_ptr<LabelPosition> > createCandidates( Pal *pal );
149 
158  std::size_t createCandidatesAroundPoint( double x, double y, std::vector<std::unique_ptr<LabelPosition> > &lPos, double angle );
159 
168  std::size_t createCandidatesOverPoint( double x, double y, std::vector<std::unique_ptr<LabelPosition> > &lPos, double angle );
169 
178  std::size_t createCandidateCenteredOverPoint( double x, double y, std::vector<std::unique_ptr<LabelPosition> > &lPos, double angle );
179 
186  std::unique_ptr< LabelPosition > createCandidatePointOnSurface( PointSet *mapShape );
187 
196  std::size_t createCandidatesAtOrderedPositionsOverPoint( double x, double y, std::vector<std::unique_ptr<LabelPosition> > &lPos, double angle );
197 
206  std::size_t createCandidatesAlongLine( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, bool allowOverrun, Pal *pal );
207 
215  std::size_t createHorizontalCandidatesAlongLine( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, Pal *pal );
216 
225  std::size_t createCandidatesAlongLineNearStraightSegments( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, Pal *pal );
226 
237  std::size_t createCandidatesAlongLineNearMidpoint( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, double initialCost = 0.0, Pal *pal = nullptr );
238 
250  std::unique_ptr< LabelPosition > curvedPlacementAtOffset( PointSet *path_positions, double *path_distances,
251  int &orientation, double distance, bool &reversed, bool &flip, bool applyAngleConstraints );
252 
261  std::size_t createCurvedCandidatesAlongLine( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, bool allowOverrun, Pal *pal );
262 
270  std::size_t createCandidatesForPolygon( std::vector<std::unique_ptr<LabelPosition> > &lPos, PointSet *mapShape, Pal *pal );
271 
278  std::size_t createCandidatesOutsidePolygon( std::vector<std::unique_ptr<LabelPosition> > &lPos, Pal *pal );
279 
286  bool hasSameLabelFeatureAs( FeaturePart *part ) const;
287 
292  double getLabelWidth( double angle = 0.0 ) const { return mLF->size( angle ).width(); }
293 
298  double getLabelHeight( double angle = 0.0 ) const { return mLF->size( angle ).height(); }
299 
304  double getLabelDistance() const { return mLF->distLabel(); }
305 
307  bool hasFixedRotation() const { return mLF->hasFixedAngle(); }
308 
310  double fixedAngle() const { return mLF->fixedAngle(); }
311 
313  bool hasFixedPosition() const { return mLF->hasFixedPosition(); }
314 
319  bool alwaysShow() const { return mLF->alwaysShow(); }
320 
324  const QgsLabelObstacleSettings &obstacleSettings() const { return mLF->obstacleSettings(); }
325 
327  double repeatDistance() const { return mLF->repeatDistance(); }
328 
330  int getNumSelfObstacles() const { return mHoles.count(); }
332  FeaturePart *getSelfObstacle( int i ) { return mHoles.at( i ); }
333 
335  bool isConnected( FeaturePart *p2 );
336 
341  bool mergeWithFeaturePart( FeaturePart *other );
342 
348  void addSizePenalty( std::vector<std::unique_ptr<LabelPosition> > &lPos, double bbx[4], double bby[4] );
349 
354  double calculatePriority() const;
355 
357  bool showUprightLabels() const;
358 
360  bool nextCharPosition( double charWidth, double segmentLength, PointSet *path_positions, int &index, double &currentDistanceAlongSegment,
361  double &characterStartX, double &characterStartY, double &characterEndX, double &characterEndY ) const;
362 
367  int totalRepeats() const;
368 
373  void setTotalRepeats( int repeats );
374 
375  protected:
376 
377  QgsLabelFeature *mLF = nullptr;
378  QList<FeaturePart *> mHoles;
379 
381  void extractCoords( const GEOSGeometry *geom );
382 
383  private:
384 
385  LabelPosition::Quadrant quadrantFromOffset() const;
386 
387  int mTotalRepeats = 0;
388 
389  mutable std::size_t mCachedMaxLineCandidates = 0;
390  mutable std::size_t mCachedMaxPolygonCandidates = 0;
391 
392  FeaturePart &operator= ( const FeaturePart & ) = delete;
393  };
394 
395 } // end namespace pal
396 
397 #endif
The QgsLabelFeature class describes a feature that should be used within the labeling engine.
Contains settings related to how the label engine treats features as obstacles.
Main class to handle feature.
Definition: feature.h:97
bool hasFixedRotation() const
Returns true if the feature's label has a fixed rotation.
Definition: feature.h:307
double getLabelHeight(double angle=0.0) const
Returns the height of the label, optionally taking an angle into account.
Definition: feature.h:298
QList< FeaturePart * > mHoles
Definition: feature.h:378
double getLabelDistance() const
Returns the distance from the anchor point to the label.
Definition: feature.h:304
bool hasFixedPosition() const
Returns true if the feature's label has a fixed position.
Definition: feature.h:313
double fixedAngle() const
Returns the fixed angle for the feature's label.
Definition: feature.h:310
double repeatDistance() const
Returns the distance between repeating labels for this feature.
Definition: feature.h:327
int getNumSelfObstacles() const
Gets number of holes (inner rings) - they are considered as obstacles.
Definition: feature.h:330
const QgsLabelObstacleSettings & obstacleSettings() const
Returns the feature's obstacle settings.
Definition: feature.h:324
double getLabelWidth(double angle=0.0) const
Returns the width of the label, optionally taking an angle into account.
Definition: feature.h:292
bool alwaysShow() const
Returns true if the feature's label should always been shown, even when it collides with other labels...
Definition: feature.h:319
FeaturePart * getSelfObstacle(int i)
Gets hole (inner ring) - considered as obstacle.
Definition: feature.h:332
QgsLabelFeature * feature()
Returns the parent feature.
Definition: feature.h:118
Optional additional info about label (for curved labels)
Definition: feature.h:56
LabelInfo & operator=(const LabelInfo &rh)=delete
LabelInfo cannot be copied.
double max_char_angle_outside
Definition: feature.h:80
LabelInfo(const LabelInfo &rh)=delete
LabelInfo cannot be copied.
LabelInfo(int num, double height, double maxinangle=20.0, double maxoutangle=-20.0)
Definition: feature.h:63
int char_num
Definition: feature.h:82
double max_char_angle_inside
Definition: feature.h:79
double label_height
Definition: feature.h:81
LabelPosition is a candidate feature label position.
Definition: labelposition.h:56
Quadrant
Position of label candidate relative to feature.
Definition: labelposition.h:66
A set of features which influence the labeling process.
Definition: layer.h:62
Main Pal labeling class.
Definition: pal.h:80
The underlying raw pal geometry class.
Definition: pointset.h:76
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)
Definition: MathUtils.cpp:786
qint64 QgsFeatureId
64 bit feature ids negative numbers are used for uncommitted/newly added features
Definition: qgsfeatureid.h:28