add an example with IO for a .mesh file

Mesh_3/include/CGAL/IO/File_medit.h

@@ -893,6 +893,26 @@ output_to_medit(std::ostream& os,
   }
 }
 
+
+template<typename T3>
+void
+output_triangulation_to_medit(std::ostream& os, const T3& t3)
+{
+  CGAL::Mesh_complex_3_in_triangulation_3<T3, int, int> c3t3;
+  c3t3.triangulation() = t3;
+  c3t3.rescan_after_load_of_triangulation();
+  output_to_medit(os, c3t3);
+}
+
+template<typename T3>
+bool input_medit(std::istream& in, T3& t3)
+{
+//  in.open(fileinfo.filePath().toUtf8(), std::ios_base::in);//not binary
+  CGAL_assertion(!(!in));
+
+  return CGAL::build_triangulation_from_file<T3, true>(in, t3);
+}
+
 } // end namespace CGAL
 
 #endif // CGAL_IO_FILE_MEDIT_H

Tetrahedral_remeshing/examples/Tetrahedral_remeshing/CMakeLists.txt

@@ -28,6 +28,7 @@ include(CGAL_Eigen_support)
 create_single_source_cgal_program( "tetrahedral_remeshing_example.cpp" )
 create_single_source_cgal_program( "tetrahedral_remeshing_with_features.cpp")
 create_single_source_cgal_program( "tetrahedral_remeshing_of_one_subdomain.cpp")
+create_single_source_cgal_program( "tetrahedral_remeshing_from_mesh.cpp")
 
 create_single_source_cgal_program( "mesh_and_remesh_polyhedral_domain_with_features.cpp" )
 target_link_libraries(mesh_and_remesh_polyhedral_domain_with_features PUBLIC CGAL::Eigen_support)

Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_from_mesh.cpp

@@ -0,0 +1,34 @@
+#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+
+#include <CGAL/IO/File_medit.h>
+
+#include <iostream>
+#include <fstream>
+#include <string>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+int main(int argc, char* argv[])
+{
+  const char* filename = (argc > 1) ? argv[1] : "data/sphere.mesh";
+  const double target_edge_length = (argc > 2) ? atof(argv[2]) : 0.1;
+
+  std::ifstream is(filename, std::ios_base::in);
+
+  Remeshing_triangulation tr;
+  CGAL::input_medit(is, tr);
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length);
+
+  std::ofstream os("after_remeshing.mesh");
+  CGAL::output_triangulation_to_medit(os, tr);
+
+  return EXIT_SUCCESS;
+}