QGIS API Documentation  2.99.0-Master (53aba61)
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 "rtree.hpp"
41 #include <iostream>
42 #include <fstream>
43 #include <cmath>
44 #include <QString>
45 
51 namespace pal
52 {
54  class CORE_EXPORT LabelInfo
55  {
56  public:
57  typedef struct
58  {
59  double width;
60  } CharacterInfo;
61 
62  LabelInfo( int num, double height, double maxinangle = 20.0, double maxoutangle = -20.0 )
63  {
64  max_char_angle_inside = maxinangle;
65  // outside angle should be negative
66  max_char_angle_outside = maxoutangle > 0 ? -maxoutangle : maxoutangle;
67  label_height = height;
68  char_num = num;
69  char_info = new CharacterInfo[num];
70  }
71  ~LabelInfo() { delete [] char_info; }
72 
74  LabelInfo( const LabelInfo &rh ) = delete;
76  LabelInfo &operator=( const LabelInfo &rh ) = delete;
77 
80  double label_height;
81  int char_num;
82  CharacterInfo *char_info = nullptr;
83 
84  };
85 
86  class LabelPosition;
87  class FeaturePart;
88 
95  class CORE_EXPORT FeaturePart : public PointSet
96  {
97 
98  public:
99 
104  FeaturePart( QgsLabelFeature *lf, const GEOSGeometry *geom );
105 
106  FeaturePart( const FeaturePart &other );
107 
110  virtual ~FeaturePart();
111 
114  QgsLabelFeature *feature() { return mLF; }
115 
118  Layer *layer();
119 
122  QgsFeatureId featureId() const;
123 
132  int createCandidates( QList<LabelPosition *> &lPos, double bboxMin[2], double bboxMax[2], PointSet *mapShape, RTree<LabelPosition *, double, 2, double> *candidates );
133 
141  int createCandidatesAroundPoint( double x, double y, QList<LabelPosition *> &lPos, double angle );
142 
150  int createCandidatesOverPoint( double x, double y, QList<LabelPosition *> &lPos, double angle );
151 
159  int createCandidatesAtOrderedPositionsOverPoint( double x, double y, QList<LabelPosition *> &lPos, double angle );
160 
166  int createCandidatesAlongLine( QList<LabelPosition *> &lPos, PointSet *mapShape );
167 
174  int createCandidatesAlongLineNearStraightSegments( QList<LabelPosition *> &lPos, PointSet *mapShape );
175 
184  int createCandidatesAlongLineNearMidpoint( QList<LabelPosition *> &lPos, PointSet *mapShape, double initialCost = 0.0 );
185 
196  LabelPosition *curvedPlacementAtOffset( PointSet *path_positions, double *path_distances,
197  int &orientation, int index, double distance, bool &reversed, bool &flip );
198 
204  int createCurvedCandidatesAlongLine( QList<LabelPosition *> &lPos, PointSet *mapShape );
205 
211  int createCandidatesForPolygon( QList<LabelPosition *> &lPos, PointSet *mapShape );
212 
218  bool hasSameLabelFeatureAs( FeaturePart *part ) const;
219 
220 #if 0
221 
226  void print();
227 #endif
228 
229  double getLabelWidth() const { return mLF->size().width(); }
230  double getLabelHeight() const { return mLF->size().height(); }
231  double getLabelDistance() const { return mLF->distLabel(); }
232 
234  bool hasFixedRotation() const { return mLF->hasFixedAngle(); }
235 
237  double fixedAngle() const { return mLF->fixedAngle(); }
238 
240  bool hasFixedPosition() const { return mLF->hasFixedPosition(); }
241 
244  bool alwaysShow() const { return mLF->alwaysShow(); }
245 
247  bool isObstacle() const { return mLF->isObstacle(); }
248 
251  double obstacleFactor() const { return mLF->obstacleFactor(); }
252 
254  double repeatDistance() const { return mLF->repeatDistance(); }
255 
257  int getNumSelfObstacles() const { return mHoles.count(); }
259  FeaturePart *getSelfObstacle( int i ) { return mHoles.at( i ); }
260 
262  bool isConnected( FeaturePart *p2 );
263 
266  bool mergeWithFeaturePart( FeaturePart *other );
267 
268  void addSizePenalty( int nbp, QList<LabelPosition *> &lPos, double bbx[4], double bby[4] );
269 
275  double calculatePriority() const;
276 
278  bool showUprightLabels() const;
279 
281  bool nextCharPosition( double charWidth, double segment_length, PointSet *path_positions, int &index, double &distance,
282  double &start_x, double &start_y, double &end_x, double &end_y ) const;
283 
284  protected:
285 
286  QgsLabelFeature *mLF = nullptr;
287  QList<FeaturePart *> mHoles;
288 
290  void extractCoords( const GEOSGeometry *geom );
291 
292  private:
293 
294  LabelPosition::Quadrant quadrantFromOffset() const;
295  };
296 
297 } // end namespace pal
298 
299 #endif
double obstacleFactor() const
Returns the feature&#39;s obstacle factor, which represents the penalty incurred for a label to overlap t...
Definition: feature.h:251
double fixedAngle() const
Returns the fixed angle for the feature&#39;s label.
Definition: feature.h:237
double max_char_angle_outside
Definition: feature.h:79
QgsLabelFeature * feature()
Returns the parent feature.
Definition: feature.h:114
bool hasFixedRotation() const
Returns true if the feature&#39;s label has a fixed rotation.
Definition: feature.h:234
A set of features which influence the labeling process.
Definition: layer.h:63
bool alwaysShow() const
Returns true if the feature&#39;s label should always been shown, even when it collides with other labels...
Definition: feature.h:244
int getNumSelfObstacles() const
Get number of holes (inner rings) - they are considered as obstacles.
Definition: feature.h:257
LabelInfo(int num, double height, double maxinangle=20.0, double maxoutangle=-20.0)
Definition: feature.h:62
double getLabelDistance() const
Definition: feature.h:231
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
double repeatDistance() const
Returns the distance between repeating labels for this feature.
Definition: feature.h:254
bool isObstacle() const
Returns true if the feature should act as an obstacle to labels.
Definition: feature.h:247
Optional additional info about label (for curved labels)
Definition: feature.h:54
double label_height
Definition: feature.h:80
double getLabelHeight() const
Definition: feature.h:230
Main class to handle feature.
Definition: feature.h:95
bool hasFixedPosition() const
Returns true if the feature&#39;s label has a fixed position.
Definition: feature.h:240
The QgsLabelFeature class describes a feature that should be used within the labeling engine...
QList< FeaturePart * > mHoles
Definition: feature.h:287
double max_char_angle_inside
Definition: feature.h:78
FeaturePart * getSelfObstacle(int i)
Get hole (inner ring) - considered as obstacle.
Definition: feature.h:259
double getLabelWidth() const
Definition: feature.h:229
LabelPosition is a candidate feature label position.
Definition: labelposition.h:55
qint64 QgsFeatureId
Definition: qgsfeature.h:37
Quadrant
Position of label candidate relative to feature.
Definition: labelposition.h:65
int char_num
Definition: feature.h:81