QGIS API Documentation  3.18.1-Zürich (202f1bf7e5)
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 
56  struct Chain
57  {
58  int degree;
59  double delta;
60  int *feat = nullptr;
61  int *label = nullptr;
62  };
63 
70  class CORE_EXPORT Problem
71  {
72  friend class Pal;
73 
74  public:
75 
81  Problem( const QgsRectangle &extent );
82 
83  //Problem(char *lorena_file, bool displayAll);
84 
86 
88  Problem( const Problem &other ) = delete;
90  Problem &operator=( const Problem &other ) = delete;
91 
97  void addCandidatePosition( std::unique_ptr< LabelPosition > position ) { mLabelPositions.emplace_back( std::move( position ) ); }
98 
102  std::size_t featureCount() const { return mFeatureCount; }
103 
107  int featureCandidateCount( int feature ) const { return mFeatNbLp[feature]; }
108 
112  LabelPosition *featureCandidate( int feature, int candidate ) const { return mLabelPositions[ mFeatStartId[feature] + candidate ].get(); }
113 
114  void reduce();
115 
119  void chain_search();
120 
133  QList<LabelPosition *> getSolution( bool returnInactive, QList<LabelPosition *> *unlabeled = nullptr );
134 
135  /* useful only for postscript post-conversion*/
136  //void toFile(char *label_file);
137 
138  void init_sol_falp();
139 
146  std::vector< std::unique_ptr< LabelPosition > > *positionsWithNoCandidates()
147  {
148  return &mPositionsWithNoCandidates;
149  }
150 
154  PalRtree< LabelPosition > &allCandidatesIndex() { return mAllCandidatesIndex; }
155 
156  private:
157 
161  int mLayerCount = 0;
162 
166  QStringList labelledLayersName;
167 
171  int mTotalCandidates = 0;
172 
176  int mAllNblp = 0;
177 
181  std::size_t mFeatureCount = 0;
182 
186  bool mDisplayAll = false;
187 
191  double mMapExtentBounds[4] = {0, 0, 0, 0};
192 
193  std::vector< std::unique_ptr< LabelPosition > > mLabelPositions;
194 
195  PalRtree<LabelPosition> mAllCandidatesIndex;
196  PalRtree<LabelPosition> mActiveCandidatesIndex;
197 
198  std::vector< std::unique_ptr< LabelPosition > > mPositionsWithNoCandidates;
199 
200  std::vector< int > mFeatStartId;
201  std::vector< int > mFeatNbLp;
202  std::vector< double > mInactiveCost;
203 
204  class Sol
205  {
206  public:
207 
209  std::vector< int > activeLabelIds;
210 
211  double totalCost = 0;
212 
213  void init( std::size_t featureCount )
214  {
215  activeLabelIds.resize( featureCount, -1 );
216  totalCost = 0;
217  }
218  };
219 
220  Sol mSol;
221  double mNbOverlap = 0.0;
222 
223  Chain *chain( int seed );
224 
225  Pal *pal = nullptr;
226 
227  void solution_cost();
228  };
229 
230 } // namespace
231 
232 #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
Representation of a labeling problem.
Definition: problem.h:71
LabelPosition * featureCandidate(int feature, int candidate) const
Returns the candidate corresponding to the specified feature and candidate index.
Definition: problem.h:112
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:146
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:97
int featureCandidateCount(int feature) const
Returns the number of candidates generated for the feature at the specified index.
Definition: problem.h:107
std::size_t featureCount() const
Returns the total number of features considered during the labeling problem.
Definition: problem.h:102
PalRtree< LabelPosition > & allCandidatesIndex()
Returns the index containing all label candidates.
Definition: problem.h:154
Problem(const Problem &other)=delete
Problem cannot be copied.
Chain solution parameters.
Definition: problem.h:47
double delta
Definition: problem.h:59
int * label
Definition: problem.h:61
int * feat
Definition: problem.h:60
int degree
Definition: problem.h:58