message: add fcuntionsin meshxd files
diff: @@ -342,6 +342,32 @@ namespace RINGMesh {
  return nb_facet_vertices( facet_id ) == 3 ;
  }
  + /*!
  + * @brief Gets the length of the edge \param edge_id on the facet \param facet_id
  + */
  + double facet_edge_length(index_t facet_id, index_t edge_id) const
  + {
  + if (edge_id == nb_facet_vertices(facet_id) - 1){
  + next_vertex =
  + const vec3& e0 = vertex(facet_vertex(facet_id,edge_id));
  + if (edge_id == nb_facet_vertices(facet_id) - 1){
  + const vec3& e1 = vertex(facet_vertex(facet_id, 0));
  + }
  + else {
  + const vec3& e1 = vertex(facet_vertex(facet_id, edge_id + 1));
  + }
  + return (e1 - e0).length();
  + }
  +
  + vec3 facet_edge_barycenter(index_t edge_id) const
  + {
  + /*
  + const vec3& e0 = vertex(edge_vertex(edge_id, 0));
  + const vec3& e1 = vertex(edge_vertex(edge_id, 1));
  + return (e1 + e0) / 2.;
  + */
  + }
  +
  /*!
  * Computes the Mesh facet normal
  * @param[in] facet_id the facet index
  @@ -490,6 +516,11 @@ namespace RINGMesh {
  * @return the global facet index.
  */
  virtual index_t cell_facet( index_t cell_id, index_t facet_id ) const = 0 ;
  + cell_edge?
  + double cell_facet_edge_length(index_t cell_id, index_t facet_id, index_t edge_id){}
  + vec3 cell_facet_edge_barycenter(index_t cell_id, index_t facet_id, index_t edge_id){}
  + double cell_edge_length(index_t cell_id, index_t edge_id){}
  + vec3 cell_edge_barycenter(index_t cell_id, index_t edge_id){}
  /*!
  * @brief Gets the number of facet in a cell
  