1 #include <CGAL/Linear_cell_complex_for_combinatorial_map.h>
2 #include <CGAL/Linear_cell_complex_constructors.h>
3 #include <CGAL/Timer.h>
4 #include <iostream>
5 #include <fstream>
6 
7 typedef CGAL::Linear_cell_complex_for_combinatorial_map<2,3> LCC_3;
8 typedef LCC_3::Dart_handle             Dart_handle;
9 typedef LCC_3::Point                   Point;
10 typedef LCC_3::FT                      FT;
11 
load_and_simplify_off(LCC_3 & lcc,const std::string & filename,bool updateattribs,int percent)12 void load_and_simplify_off(LCC_3& lcc, const std::string& filename,
13                            bool updateattribs, int percent)
14 {
15   std::ifstream ifile(filename.c_str());
16   if (ifile)
17   {
18     CGAL::load_off(lcc, ifile);
19     CGAL::Timer timer;
20     Dart_handle dh;
21     std::size_t nb=(lcc.number_of_darts()*percent)/200;
22     timer.start();
23 
24     if (!updateattribs) lcc.set_automatic_attributes_management(false);
25     for (LCC_3::Dart_range::iterator it=lcc.darts().begin(),
26            itend=lcc.darts().end(); it!=itend && nb>0; )
27     {
28       dh=it++;
29       if ( it!=itend && it==lcc.beta<2>(dh) ) ++it;
30       lcc.remove_cell<1>(dh);
31       --nb;
32     }
33     if ( !updateattribs ) lcc.set_automatic_attributes_management(true);
34 
35     timer.stop();
36     lcc.display_characteristics(std::cout);
37     std::cout<<", valid="<< lcc.is_valid()
38              <<" time: "<<timer.time()<<" seconds." << std::endl;
39   }
40 }
41 
main(int narg,char ** argv)42 int main(int narg, char** argv)
43 {
44   if (narg>1 && (!strcmp(argv[1],"-h") || !strcmp(argv[1],"-?")) )
45   {
46     std::cout<<"Usage: a.out file.off [percentage]"<<std::endl;
47     return EXIT_FAILURE;
48   }
49 
50   std::string filename;
51   if ( narg==1 )
52   {
53     filename=std::string("data/armadillo.off");
54     std::cout<<"No filename given: use data/armadillo.off by default."<<std::endl;
55   }
56   else filename=std::string(argv[1]);
57 
58   int percent = 30; // remove 30 percent of edges
59   if ( narg>2 ) { percent = atoi(argv[2]); }
60   std::cout<<percent<<"% edges to remove."<<std::endl;
61 
62   LCC_3 lcc;
63   std::cout<<"Update attribute DURING operations: ";
64   load_and_simplify_off(lcc, filename, true, percent);
65 
66   LCC_3 lcc2;
67   std::cout<<"Update attribute AFTER operations: ";
68   load_and_simplify_off(lcc2, filename, false, percent);
69 
70   return EXIT_SUCCESS;
71 }
72