Export to OFF (2D & 3D triangulations)

Triangulation/include/CGAL/IO/Triangulation_io.h

@@ -33,13 +33,12 @@ std::ostream &
 operator<<(std::ostream & os, const typename Wrap::Point_d<K> & p)
 {
   typename K::Cartesian_const_iterator_d it = p.cartesian_begin();
-  os << "(" << *it;
+  os << *it;
   ++it;
   for ( ; it != p.cartesian_end() ; ++it)
   {
-    os << ", " << *it;
+    os << " " << *it;
   }
-  os << ")";
   return os;
 }
 
@@ -58,6 +57,90 @@ operator<<(std::ostream & os, const Triangulation_vertex<A, Data, B> & v)
   return os;
 }*/
 
+
+template<typename Tr>
+std::ostream &
+export_triangulation_to_off(std::ostream & os, const Tr & tr)
+{
+  typedef typename Tr::Vertex_const_handle              Vertex_handle;
+  typedef typename Tr::Vertex_const_iterator            Vertex_iterator;
+  typedef typename Tr::Finite_vertex_const_iterator     Finite_vertex_iterator;
+  typedef typename Tr::Full_cell_const_handle           Full_cell_handle;
+  typedef typename Tr::Finite_full_cell_const_iterator  Finite_full_cell_iterator;
+  typedef typename Tr::Full_cell_const_iterator         Full_cell_iterator;
+  typedef typename Tr::Full_cell                        Full_cell;
+  typedef typename Full_cell::Vertex_handle_const_iterator Full_cell_vertex_iterator;
+  
+  if (tr.maximal_dimension() < 2 || tr.maximal_dimension() > 3)
+  {
+    std::cerr << "Warning: export_tds_to_off => dimension should be 2 or 3.";
+    os << "Warning: export_tds_to_off => dimension should be 2 or 3.";
+    return os;
+  }
+
+  size_t n = tr.number_of_vertices();
+
+  std::stringstream output;
+  
+  // write the vertices
+  std::map<Vertex_handle, int> index_of_vertex;
+  int i = 0;
+  for(Finite_vertex_iterator it = tr.finite_vertices_begin(); 
+      it != tr.finite_vertices_end(); ++it, ++i)
+  {
+    output << *it;
+    if (tr.maximal_dimension() == 2)
+      output << " 0";
+    output << std::endl;
+    index_of_vertex[it.base()] = i;
+  }
+  CGAL_assertion( i == n );
+  
+  size_t number_of_triangles = 0;
+  if (tr.maximal_dimension() == 2)
+  {
+    for (Finite_full_cell_iterator fch = tr.finite_full_cells_begin() ;
+         fch != tr.finite_full_cells_end() ; ++fch)
+    {
+      output << "3 ";
+      for (Full_cell_vertex_iterator vit = fch->vertices_begin() ;
+           vit != fch->vertices_end() ; ++vit)
+      {
+        output << index_of_vertex[*vit] << " ";
+      }
+      output << std::endl;
+      ++number_of_triangles;
+    }
+  }
+  else if (tr.maximal_dimension() == 3)
+  {
+    // Parse boundary facets
+    for (Full_cell_iterator fch = tr.full_cells_begin() ;
+         fch != tr.full_cells_end() ; ++fch)
+    {
+      if (tr.is_infinite(fch))
+      {
+        output << "3 ";
+        for (Full_cell_vertex_iterator vit = fch->vertices_begin() ;
+             vit != fch->vertices_end() ; ++vit, ++i)
+        {
+          if (!tr.is_infinite(*vit))
+            output << index_of_vertex[*vit] << " ";
+        }
+        output << std::endl;
+        ++number_of_triangles; 
+      }
+    }
+  }
+
+  os << "OFF \n"
+     << n << " " 
+     << number_of_triangles << " 0\n"
+     << output.str();
+
+  return os;
+}
+
 } //namespace CGAL
 
 #endif // CGAL_TRIANGULATION_IO_H