QGIS API Documentation  3.21.0-Master (909859188c)
problem.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_PROBLEM_H
31 #define PAL_PROBLEM_H
32 
33 #define SIP_NO_FILE
34 
35 
36 #include "qgis_core.h"
37 #include <list>
38 #include <QList>
39 #include "palrtree.h"
40 #include <memory>
41 #include <vector>
42 
43 namespace pal
44 {
45 
46  class LabelPosition;
47  class Label;
48  class PriorityQueue;
49 
57  struct Chain
58  {
59  int degree;
60  double delta;
61  int *feat = nullptr;
62  int *label = nullptr;
63  };
64 
71  class CORE_EXPORT Problem
72  {
73  friend class Pal;
74 
75  public:
76 
82  Problem( const QgsRectangle &extent );
83 
84  //Problem(char *lorena_file, bool displayAll);
85 
87 
89  Problem( const Problem &other ) = delete;
91  Problem &operator=( const Problem &other ) = delete;
92 
98  void addCandidatePosition( std::unique_ptr< LabelPosition > position ) { mLabelPositions.emplace_back( std::move( position ) ); }
99 
103  std::size_t featureCount() const { return mFeatureCount; }
104 
108  int featureCandidateCount( int feature ) const { return mFeatNbLp[feature]; }
109 
113  LabelPosition *featureCandidate( int feature, int candidate ) const { return mLabelPositions[ mFeatStartId[feature] + candidate ].get(); }
114 
115  void reduce();
116 
120  void chain_search();
121 
134  QList<LabelPosition *> getSolution( bool returnInactive, QList<LabelPosition *> *unlabeled = nullptr );
135 
136  /* useful only for postscript post-conversion*/
137  //void toFile(char *label_file);
138 
139  void init_sol_falp();
140 
147  std::vector< std::unique_ptr< LabelPosition > > *positionsWithNoCandidates()
148  {
149  return &mPositionsWithNoCandidates;
150  }
151 
155  PalRtree< LabelPosition > &allCandidatesIndex() { return mAllCandidatesIndex; }
156 
157  private:
158 
162  bool candidatesAreConflicting( const LabelPosition *lp1, const LabelPosition *lp2 ) const;
163 
167  int mLayerCount = 0;
168 
172  QStringList labelledLayersName;
173 
177  int mTotalCandidates = 0;
178 
182  int mAllNblp = 0;
183 
187  std::size_t mFeatureCount = 0;
188 
192  bool mDisplayAll = false;
193 
197  double mMapExtentBounds[4] = {0, 0, 0, 0};
198 
199  std::vector< std::unique_ptr< LabelPosition > > mLabelPositions;
200 
201  PalRtree<LabelPosition> mAllCandidatesIndex;
202  PalRtree<LabelPosition> mActiveCandidatesIndex;
203 
204  std::vector< std::unique_ptr< LabelPosition > > mPositionsWithNoCandidates;
205 
206  std::vector< int > mFeatStartId;
207  std::vector< int > mFeatNbLp;
208  std::vector< double > mInactiveCost;
209 
210  class Sol
211  {
212  public:
213 
215  std::vector< int > activeLabelIds;
216 
217  double totalCost = 0;
218 
219  void init( std::size_t featureCount )
220  {
221  activeLabelIds.resize( featureCount, -1 );
222  totalCost = 0;
223  }
224  };
225 
226  Sol mSol;
227  double mNbOverlap = 0.0;
228 
229  Chain *chain( int seed );
230 
231  Pal *pal = nullptr;
232 
233  void solution_cost();
234  void ignoreLabel( const LabelPosition *lp, pal::PriorityQueue &list, PalRtree<LabelPosition> &candidatesIndex );
235  };
236 
237 } // namespace
238 
239 #endif
A rtree spatial index for use in the pal labeling engine.
Definition: palrtree.h:36
A rectangle specified with double values.
Definition: qgsrectangle.h:42
LabelPosition is a candidate feature label position.
Definition: labelposition.h:56
Main Pal labeling class.
Definition: pal.h:80
Custom priority queue for use in pal labeling engine.
Definition: priorityqueue.h:53
Representation of a labeling problem.
Definition: problem.h:72
LabelPosition * featureCandidate(int feature, int candidate) const
Returns the candidate corresponding to the specified feature and candidate index.
Definition: problem.h:113
std::vector< std::unique_ptr< LabelPosition > > * positionsWithNoCandidates()
Returns a reference to the list of label positions which correspond to features with no candidates.
Definition: problem.h:147
Problem & operator=(const Problem &other)=delete
Problem cannot be copied.
void addCandidatePosition(std::unique_ptr< LabelPosition > position)
Adds a candidate label position to the problem.
Definition: problem.h:98
int featureCandidateCount(int feature) const
Returns the number of candidates generated for the feature at the specified index.
Definition: problem.h:108
std::size_t featureCount() const
Returns the total number of features considered during the labeling problem.
Definition: problem.h:103
PalRtree< LabelPosition > & allCandidatesIndex()
Returns the index containing all label candidates.
Definition: problem.h:155
Problem(const Problem &other)=delete
Problem cannot be copied.
Chain solution parameters.
Definition: problem.h:48
double delta
Definition: problem.h:60
int * label
Definition: problem.h:62
int * feat
Definition: problem.h:61
int degree
Definition: problem.h:59