TRUST_2_CGNS.cpp

/****************************************************************************
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#include <Domaine_dis_cache.h>
#include <communications.h>
#include <Comm_Group_MPI.h>
#include <TRUST_2_CGNS.h>
#include <unordered_set>
#include <Domaine_VF.h>
#include <Domaine.h>
#include <cstring>
 
#ifdef HAS_CGNS
 
namespace
{
#ifdef MPI_
bool is_comm_group_mode(const bool postraiter_domaine)
{
  return (Option_CGNS::LINKED_FILES_PER_COMM_GROUP || Option_CGNS::SINGLE_FILE_PER_COMM_GROUP)
         && Process::is_parallel() && PE_Groups::has_user_defined_group() && !postraiter_domaine;
}
 
void allgather_int_on_active_comm(const int local_value, std::vector<int>& global_values, const bool by_comm_grp)
{
  if (by_comm_grp)
    {
      const Comm_Group_MPI& comm_loc = ref_cast(Comm_Group_MPI, PE_Groups::get_user_defined_group());
      MPI_Allgather(&local_value, 1, MPI_ENTIER, global_values.data(), 1, MPI_ENTIER, comm_loc.get_mpi_comm());
    }
  else
    MPI_Allgather(&local_value, 1, MPI_ENTIER, global_values.data(), 1, MPI_ENTIER, MPI_COMM_WORLD);
}
 
void compute_global_min_max(const std::vector<int>& global_counts, std::vector<int>& global_min, std::vector<int>& global_max, int& total)
{
  const int nb_procs = static_cast<int>(global_counts.size());
  global_min.assign(nb_procs, -123);
  global_max.assign(nb_procs, -123);
  total = 0;
 
  for (int i = 0; i < nb_procs; i++)  // now we fill global incremented min/max stuff
    {
      global_min[i] = total + 1; // 1 : min
      total += global_counts[i]; // 2 : increment
      global_max[i] = total; // 3 : max
    }
}
 
void compute_global_max_only(const std::vector<int>& global_counts, std::vector<int>& global_max, int& total)
{
  const int nb_procs = static_cast<int>(global_counts.size());
  global_max.assign(nb_procs, -123);
  total = 0;
 
  for (int i = 0; i < nb_procs; i++)
    {
      total += global_counts[i]; // 1 : increment
      global_max[i] = total; // 2 : max
    }
}
#endif
}
 
Motcle TRUST_2_CGNS::modify_field_name_for_post(const Nom& id_du_champ, const Nom& id_du_domaine, const std::string& LOC, int& fieldId_som, int& fieldId_elem, int& fieldId_faces)
{
  Motcle id_du_champ_modifie(id_du_champ), iddomaine(id_du_domaine);
 
  if (LOC == "SOM")
    {
      id_du_champ_modifie.prefix(id_du_domaine);
      id_du_champ_modifie.prefix(iddomaine);
      id_du_champ_modifie.prefix("_SOM_");
    }
  else if (LOC == "ELEM")
    {
      id_du_champ_modifie.prefix(id_du_domaine);
      id_du_champ_modifie.prefix(iddomaine);
      id_du_champ_modifie.prefix("_ELEM_");
    }
  else if (LOC == "FACES")
    {
      id_du_champ_modifie.prefix(id_du_domaine);
      id_du_champ_modifie.prefix(iddomaine);
      id_du_champ_modifie.prefix("_FACES_");
    }
  else
    throw std::runtime_error("TRUST_2_CGNS::modify_field_name_for_post => Unsupported LOC : " + LOC);
 
  (LOC == "SOM") ? fieldId_som++ : ( (LOC == "ELEM") ? fieldId_elem++ : fieldId_faces++);
 
  /*
   * XXX Elie Saikali : in CGNS we are limited to char size 32 max ! otherwise not supported (see method cgi_check_strlen ...)
   * Go Bricorama !
   */
 
  const char * id_char = id_du_champ_modifie.getChar();
  size_t sz =  std::strlen(id_char);
  if (sz > CGNS_STR_SIZE)
    {
#ifndef NDEBUG
      Cerr << "The field " << id_char << " contains " << sz << " chars & CGNS is limited to " << CGNS_STR_SIZE << " ==> renamed to ";
#endif
 
      std::string new_id_du_champ_modifie(id_char);
 
      auto replace_all = [](std::string& s, const std::string& from, const std::string& to)
      {
        size_t pos = 0;
        while ((pos = s.find(from, pos)) != std::string::npos)
          {
            s.replace(pos, from.length(), to);
            pos += to.length();
          }
      };
 
      // 1. First attempt: remove case name prefix if needed
      Motcle truncate_try_1(id_du_champ_modifie), nom_du_cas(Objet_U::nom_du_cas());
      truncate_try_1.suffix(nom_du_cas.getChar());
      truncate_try_1.suffix("_");
 
      if (std::strlen(truncate_try_1.getChar()) <= CGNS_STR_SIZE)
        new_id_du_champ_modifie = truncate_try_1.getChar();
 
 
      // 2. If still too long, try a few abbreviation replacements
      if (new_id_du_champ_modifie.size() > CGNS_STR_SIZE)
        {
          replace_all(new_id_du_champ_modifie, "VITESSE", "VIT");
          replace_all(new_id_du_champ_modifie, "TEMPERATURE", "TEMP");
          replace_all(new_id_du_champ_modifie, "CONCENTRATION", "CONC");
          replace_all(new_id_du_champ_modifie, "CONVECTION", "CONV");
          replace_all(new_id_du_champ_modifie, "DIFFUSION", "DIFF");
          replace_all(new_id_du_champ_modifie, "VISQUEUSE", "VISQ");
          replace_all(new_id_du_champ_modifie, "MASSE_VOLUMIQUE", "RHO");
          replace_all(new_id_du_champ_modifie, "LIQUIDE", "LIQ");
        }
 
      // 3. If still too long .. truly sorry !
      if (new_id_du_champ_modifie.size() > CGNS_STR_SIZE)
        {
          static constexpr size_t keep_first = 25;
          static constexpr size_t keep_last = 5;
 
          const size_t new_sz = new_id_du_champ_modifie.size();
          const std::string prem = new_id_du_champ_modifie.substr(0, keep_first);
          const std::string der = new_id_du_champ_modifie.substr(new_sz - keep_last, keep_last);
 
          new_id_du_champ_modifie = prem + "__" + der;
        }
 
      id_du_champ_modifie = Motcle(new_id_du_champ_modifie.c_str());
 
#ifndef NDEBUG
      Cerr << id_du_champ_modifie << " !!! " << finl;
#endif
    }
 
  return id_du_champ_modifie;
}
 
// to strip boundaries_ from the domain name (added by TRUST for boundary subdomains ...)
std::string TRUST_2_CGNS::modify_domaine_name_for_post(const Nom& nom_dom)
{
  std::string nom_dom_modifie = nom_dom.getString();
 
  if (static_cast<int>(nom_dom_modifie.size()) >= CGNS_STR_SIZE)
    {
      size_t found = nom_dom_modifie.find("boundaries_");
      if (found != std::string::npos)
        nom_dom_modifie.erase(found, 11); // 11 is the length of "boundaries_"
 
//      if (static_cast<int>(nom_dom_modifie.size()) >= CGNS_STR_SIZE)
//        nom_dom_modifie.resize(CGNS_STR_SIZE, ' ');
      if (static_cast<int>(nom_dom_modifie.size()) >= CGNS_STR_SIZE)
        nom_dom_modifie.erase(CGNS_STR_SIZE-1);
    }
 
  return nom_dom_modifie;
}
 
void TRUST_2_CGNS::map_face_values(const Domaine_VF& dom_vf, const DoubleTab& val_src, DoubleTrav& val_trgt)
{
  const auto& dual_m = dom_vf.get_mc_dual_mesh();
  const int nb_cells = static_cast<int>(dual_m->getNumberOfCells());
  const auto& face_voisins = dom_vf.get_face_voisins_dual();
 
  assert (val_src.nb_dim() == 2);
  const int nb_j = val_src.dimension(1);
  val_trgt.resize(nb_cells, nb_j);
 
  for (int f = 0; f < val_src.dimension(0); f++)
    {
      const int e1 = face_voisins(f, 0), e2 = face_voisins(f, 1);
      for (int e: {e1, e2})
        {
          if (e < 0) continue;
 
//          for (int comp = 0; comp < nb_j; comp++)
//            val_trgt(e, comp) = val_src(f, comp);
          std::copy_n(&val_src(f, 0), nb_j, &val_trgt(e, 0));
        }
    }
}
 
void TRUST_2_CGNS::associer_domaine_TRUST(const Domaine * dom, const Domaine_dis_base* dom_dis, const DoubleTab& som, const IntTab& elem, const bool post_dom, const std::string& discr_type)
{
  if (dom) dom_trust_ = *dom;
  if (dom_dis) domaine_dis_ = *dom_dis;
  sommets_ = som;
  elems_ = elem;
  postraiter_domaine_ = post_dom;
  discr_type_ = discr_type;
}
 
void TRUST_2_CGNS::associer_connec_pour_dual(const IntTab& fs, const IntTab& ef)
{
  fs_dual_ = fs;
  ef_dual_ = ef;
}
 
void TRUST_2_CGNS::fill_coords(std::vector<double>& xCoords, std::vector<double>& yCoords, std::vector<double>& zCoords) const
{
  const int nb_som = sommets_->dimension(0), phys_dim = Objet_U::dimension;
  const DoubleTab& sommets = sommets_.valeur();
  assert (sommets_->dimension(1) > 1);
 
  xCoords.resize(nb_som);
  yCoords.resize(nb_som);
 
  if (phys_dim == 3)
    {
      assert(sommets_->dimension(1) > 2);
      zCoords.resize(nb_som);
    }
  else
    zCoords.clear();
 
  if (Objet_U::axi) // just in case
    {
      for (int i = 0; i < nb_som; ++i)
        {
          const double r = sommets(i, 0), theta = sommets(i, 1);
          xCoords[i] = r * cos(theta);
          yCoords[i] = r * sin(theta);
          if (phys_dim == 3)
            zCoords[i] = sommets(i, 2);
        }
    }
  else
    {
      for (int i = 0; i < nb_som; ++i)
        {
          xCoords[i] = sommets(i, 0);
          yCoords[i] = sommets(i, 1);
          if (phys_dim == 3)
            zCoords[i] = sommets(i, 2);
        }
    }
}
 
/*
 * NOTA BENE : postraiter_domaine_ always behaves like PARALLEL_OVER_ZONE, even when it is not active
 */
void TRUST_2_CGNS::clear_vectors()
{
  if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_) // XXX to be revisited later if still useful to keep
    {
      proc_non_zero_elem_.clear();
      global_nb_elem_.clear();
      global_nb_som_.clear();
    }
 
  // globaux
  global_nb_face_som_.clear();
  global_nb_face_som_offset_.clear();
  global_nb_elem_face_.clear();
  global_nb_elem_face_offset_.clear();
  global_nb_elem_som_offset_.clear();
 
  global_incr_min_face_som_.clear();
  global_incr_max_face_som_.clear();
  global_incr_min_elem_face_.clear();
  global_incr_max_elem_face_.clear();
 
  // locaux
  local_fs_.clear();
  local_fs_offset_.clear();
  local_ef_.clear();
  local_ef_offset_.clear();
  local_es_.clear();
  local_es_offset_.clear();
}
 
void TRUST_2_CGNS::fill_global_infos()
{
#ifdef MPI_
  assert (sommets_ && elems_);
  proc_non_zero_elem_.clear();
  all_procs_write_ = true;
 
  const bool by_comm_grp = is_comm_group_mode(postraiter_domaine_);
 
  if (by_comm_grp)
    {
      const auto& grp = PE_Groups::get_user_defined_group();
      if (PE_Groups::enter_group(grp))
        {
          proc_me_local_comm_ = Process::me();
          nb_proc_local_comm_ = Process::nproc();
          PE_Groups::exit_group();
        }
    }
  else /* otherwise, just in case ... */
    {
      proc_me_local_comm_ = Process::me();
      nb_proc_local_comm_ = Process::nproc();
    }
 
  const int nb_procs = by_comm_grp ? nb_proc_local_comm_ : Process::nproc();
  const int nb_som = sommets_->dimension(0), nb_elem = elems_->dimension(0);
 
  par_in_zone_ = (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_) ? true : false;
 
  global_nb_elem_.assign(nb_procs, -123 /* default */);
  global_nb_som_.assign(nb_procs, -123 /* default */);
 
  allgather_int_on_active_comm(nb_elem, global_nb_elem_, by_comm_grp);
  allgather_int_on_active_comm(nb_som, global_nb_som_, by_comm_grp);
 
  if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
    {
      compute_global_min_max(global_nb_elem_, global_incr_min_elem_, global_incr_max_elem_, ne_tot_);
      compute_global_min_max(global_nb_som_, global_incr_min_som_, global_incr_max_som_, ns_tot_);
    }
 
  const auto min_nb_elem = std::min_element(global_nb_elem_.begin(), global_nb_elem_.end());
  nb_procs_writing_ = nb_procs; // for now
 
  if (*min_nb_elem <= 0) // not all procs will write !
    {
      // fill proc_non_zero_elem with the proc number if nb_elem > 0 !!
      for (int i = 0; i < static_cast<int>(global_nb_elem_.size()); i++)
        if (global_nb_elem_[i] > 0) proc_non_zero_elem_.push_back(i);
 
      nb_procs_writing_ = static_cast<int>(proc_non_zero_elem_.size());
      all_procs_write_ = false;
    }
#endif
}
 
void TRUST_2_CGNS::get_domaine_dis_vf_if_poly(Domaine_dis_base*& domaine_dis, Domaine_VF*& vf)
{
  assert(dom_trust_);
  domaine_dis = nullptr;
  vf = nullptr;
 
  if (!fs_dual_ && !ef_dual_)
    {
      if (domaine_dis_
          && domaine_dis_->domaine().le_nom() == dom_trust_->le_nom() // XXX peut etre sous_zone ;)
          && domaine_dis_->face_sommets().size() > 0)  // see if well filled for example
        {
          domaine_dis = &(domaine_dis_.valeur());
        }
      else
        {
          if (discr_type_ != "")
            domaine_dis = &(Domaine_dis_cache::Build_or_get_poly_post(discr_type_, dom_trust_.valeur()));
          else
            {
              // the user seems to post the domaine before discretizing the domain of before filling the post bloc ... we try our chance with Domaine_PolyMAC_MPFA
              Nom type = "Domaine_PolyMAC_MPFA";
              domaine_dis = &(Domaine_dis_cache::Build_or_get_poly_post(type, dom_trust_.valeur()));
            }
        }
 
      vf = &(ref_cast (Domaine_VF, *domaine_dis));
    }
}
 
void TRUST_2_CGNS::fill_global_infos_poly(const bool is_polyedre)
{
#ifdef MPI_
  assert(dom_trust_);
 
  const bool by_comm_grp = is_comm_group_mode(postraiter_domaine_);
 
  int decal = 0; // to be updated later !!!
  const int nb_procs = by_comm_grp ? nb_proc_local_comm_ : Process::nproc();
 
  par_in_zone_ = (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_) ? true : false;
 
  if (is_polyedre)
    {
      Domaine_dis_base* domaine_dis = nullptr;
      Domaine_VF* vf = nullptr;
      get_domaine_dis_vf_if_poly(domaine_dis, vf);
 
      const IntTab& fs = vf ? (*vf).face_sommets() : fs_dual_.valeur();
      const IntTab& ef = vf ? (*vf).elem_faces() : ef_dual_.valeur();
      const int nb_fs = fs.dimension(0), nb_ef = ef.dimension(0);
 
      global_nb_face_som_.assign(nb_procs, -123 /* default */);
      global_nb_elem_face_.assign(nb_procs, -123 /* default */);
 
      allgather_int_on_active_comm(nb_fs, global_nb_face_som_, by_comm_grp);
      allgather_int_on_active_comm(nb_ef, global_nb_elem_face_, by_comm_grp);
 
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        {
          compute_global_min_max(global_nb_face_som_, global_incr_min_face_som_, global_incr_max_face_som_, nfs_tot_);
          compute_global_min_max(global_nb_elem_face_, global_incr_min_elem_face_, global_incr_max_elem_face_, nef_tot_);
        }
 
      // face_sommets : local vectors + offset
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        decal = compute_shift(global_incr_max_som_); // shift by sommets !!
 
      nb_fs_ = convert_connectivity_ngon(local_fs_, local_fs_offset_, is_polyedre, decal);
 
      // elem_faces : local vectors + offset
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        decal = compute_shift(global_incr_max_face_som_); // shift by faces !!
 
      nb_ef_ = convert_connectivity_nface(local_ef_, local_ef_offset_, decal);
 
      // finally: compute offset shift
      const int nb_fs_offset = static_cast<int>(local_fs_.size()), nb_ef_offset = static_cast<int>(local_ef_.size());
 
      global_nb_face_som_offset_.assign(nb_procs, -123 /* default */);
      global_nb_elem_face_offset_.assign(nb_procs, -123 /* default */);
 
      allgather_int_on_active_comm(nb_fs_offset, global_nb_face_som_offset_, by_comm_grp);
      allgather_int_on_active_comm(nb_ef_offset, global_nb_elem_face_offset_, by_comm_grp);
 
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        {
          // increment on nb_faces and nb_elem total offset
          std::vector<int> global_incr_max_face_som_offset, global_incr_max_elem_face_offset;
          compute_global_max_only(global_nb_face_som_offset_, global_incr_max_face_som_offset, nfs_offset_tot_);
          compute_global_max_only(global_nb_elem_face_offset_, global_incr_max_elem_face_offset, nef_offset_tot_);
 
          decal = compute_shift(global_incr_max_face_som_offset); // shift by faces offset !!
          for (auto &itr : local_fs_offset_) itr += decal;
 
          decal = compute_shift(global_incr_max_elem_face_offset); // shift by elem offset !!
          for (auto &itr : local_ef_offset_) itr += decal;
        }
    }
  else // polygon
    {
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        decal = compute_shift(global_incr_max_som_); // shift by sommets !!
 
      nb_es_ = convert_connectivity_ngon(local_es_, local_es_offset_, is_polyedre, decal);
 
      const int nb_es_offset = static_cast<int>(local_es_.size());
 
      // increment on nb_elem total offset
      global_nb_elem_som_offset_.assign(nb_procs, -123 /* default */);
 
      allgather_int_on_active_comm(nb_es_offset, global_nb_elem_som_offset_, by_comm_grp);
 
      if (!Option_CGNS::PARALLEL_OVER_ZONE && !postraiter_domaine_)
        {
          std::vector<int> global_incr_max_elem_som_offset;
          compute_global_max_only(global_nb_elem_som_offset_, global_incr_max_elem_som_offset, nes_offset_tot_);
 
          decal = compute_shift(global_incr_max_elem_som_offset); // shift by elem offset !!
          for (auto &itr : local_es_offset_) itr += decal;
        }
    }
#endif
}
 
int TRUST_2_CGNS::compute_shift(const std::vector<int>& vect_incr_max) const
{
#ifdef MPI_
  assert(par_in_zone_);
 
  const bool by_comm_grp = is_comm_group_mode(postraiter_domaine_);
 
  int proc_me = by_comm_grp ? proc_me_local_comm_ : Process::me();
 
  int decal = 0;
  if (all_procs_write_)
    {
      if (proc_me > 0) // not master
        decal = vect_incr_max[proc_me - 1];
    }
  else
    {
      for (int i = 0; i < nb_procs_writing_; i++)
        if (proc_non_zero_elem_[i] == proc_me)
          if (i > 0) // not the first case
            {
              decal = vect_incr_max[proc_non_zero_elem_[i] - 1];
              break;
            }
    }
  return decal;
#else
  return 0;
#endif
}
 
int TRUST_2_CGNS::convert_connectivity(const CGNS_TYPE type, std::vector<cgsize_t>& conn_elem ) const
{
  const int nb_elem = elems_->dimension(0);
  const IntTab& les_elems = elems_.valeur();
  int decal = par_in_zone_ ? compute_shift(global_incr_max_som_) : 0;
 
  int nodes_per_elem = -1;
 
  switch(type)
    {
    case CGNS_ENUMV(HEXA_8):
      nodes_per_elem = 8;
      break;
    case CGNS_ENUMV(QUAD_4):
      nodes_per_elem = 4;
      break;
    case CGNS_ENUMV(TETRA_4):
      nodes_per_elem = 4;
      break;
    case CGNS_ENUMV(TRI_3):
      nodes_per_elem = 3;
      break;
    case CGNS_ENUMV(BAR_2):
      nodes_per_elem = 2;
      break;
    case CGNS_ENUMV(NODE):
      nodes_per_elem = 1;
      break;
    default:
      Cerr << "Type not yet coded in TRUST_2_CGNS::convert_connectivity ! Call the 911 !" << finl;
      Process::exit();
      return -100;
    }
 
  if (nodes_per_elem != elems_->dimension(1))
    {
      Cerr << "Big issue in TRUST_2_CGNS::convert_connectivity !!!" << finl;
      Cerr << "   We have nodes_per_elem = " << nodes_per_elem << " while we have a connectivity of width = " << elems_->dimension(1) << finl;
      Process::exit();
      return -100;
    }
 
  conn_elem.resize(nb_elem * nodes_per_elem); // allocation une fois
  cgsize_t* data = conn_elem.data();
 
  switch(type)
    {
    case CGNS_ENUMV(HEXA_8):
      for (int i = 0; i < nb_elem; i++)
        {
          *data++ = les_elems(i, 0) + 1 + decal;
          *data++ = les_elems(i, 1) + 1 + decal;
          *data++ = les_elems(i, 3) + 1 + decal;
          *data++ = les_elems(i, 2) + 1 + decal;
          *data++ = les_elems(i, 4) + 1 + decal;
          *data++ = les_elems(i, 5) + 1 + decal;
          *data++ = les_elems(i, 7) + 1 + decal;
          *data++ = les_elems(i, 6) + 1 + decal;
        }
      break;
 
    case CGNS_ENUMV(QUAD_4):
      for (int i = 0; i < nb_elem; i++)
        {
          *data++ = les_elems(i, 0) + 1 + decal;
          *data++ = les_elems(i, 1) + 1 + decal;
          *data++ = les_elems(i, 3) + 1 + decal;
          *data++ = les_elems(i, 2) + 1 + decal;
        }
      break;
 
    case CGNS_ENUMV(TETRA_4):
    case CGNS_ENUMV(TRI_3):
    case CGNS_ENUMV(BAR_2):
    case CGNS_ENUMV(NODE):
      for (int i = 0; i < nb_elem; i++)
        for (int j = 0; j < nodes_per_elem; j++)
          *data++ = les_elems(i, j) + 1 + decal;
      break;
 
    default: /* already handled above */
      break;
    }
 
  return nodes_per_elem;
}
 
CGNS_TYPE TRUST_2_CGNS::convert_elem_type(const Motcle& type) const
{
  assert(elems_);
  const int nb_comp = elems_->dimension(1);
 
  if (type.debute_par("HEXAEDRE"))
    return CGNS_ENUMV(HEXA_8);
  else if (type.debute_par("RECTANGLE") || type.debute_par("QUADRANGLE"))
    return CGNS_ENUMV(QUAD_4);
  else if (type == "TETRAEDRE")
    return CGNS_ENUMV(TETRA_4);
  else if (type.debute_par("TRIANGLE"))
    return CGNS_ENUMV(TRI_3);
  else if (type == "POINT")
    return CGNS_ENUMV(NODE);
  else if (type == "POLYEDRE" || type.debute_par("POLYGONE") || type.debute_par("PRISME"))
    return CGNS_ENUMV(NGON_n);
  else if (type.debute_par("SEGMENT"))
    {
      /* So bad ... EF defined Bds as segments not points ... */
      if (nb_comp == 1) return CGNS_ENUMV(NODE);
      if (nb_comp == 2) return CGNS_ENUMV(BAR_2);
 
      Cerr << "Unexpected SEGMENT connectivity of width = " << nb_comp << finl;
      return CGNS_ENUMV(ElementTypeNull);
    }
  else
    {
      Cerr << "The type " << type << " is not yet available for the CGNS format ! Call the 911 !" << finl;
      Process::exit();
      return CGNS_ENUMV(ElementTypeNull);
    }
}
 
int TRUST_2_CGNS::topo_dim_from_elem(CGNS_TYPE etype, bool is_polyedre) const
{
  if (etype == CGNS_ENUMV(BAR_2) || etype == CGNS_ENUMV(NODE))
    return 1; // 1D
 
  if (etype == CGNS_ENUMV(TRI_3) || etype == CGNS_ENUMV(QUAD_4))
    return 2; // 2D classiques
 
  if (etype == CGNS_ENUMV(NGON_n))
    return is_polyedre ? 3 : 2; // NGON_n : 2D if polygon, 3D if polyhedron (with NFACE_n)
 
  // 3D classiques
  return 3; // TETRA_4, HEXA_8, NFACE_n
}
 
int TRUST_2_CGNS::convert_connectivity_nface(std::vector<cgsize_t>& econ, std::vector<cgsize_t>& eoff, int decal)
{
  assert (dom_trust_);
 
  Domaine_dis_base *domaine_dis = nullptr;
  Domaine_VF *vf = nullptr;
  get_domaine_dis_vf_if_poly(domaine_dis, vf);
 
  const IntTab& ef = vf ? (*vf).elem_faces() : ef_dual_.valeur();
 
  const int nElem = ef.dimension(0), maxDeg = ef.dimension(1);
 
  econ.clear(), eoff.clear();
 
  econ.reserve(static_cast<size_t>(nElem) * maxDeg); // each element has at most maxDeg faces
  eoff.reserve(static_cast<size_t>(nElem) + 1); // one per element + 1 for the end
 
  eoff.push_back(0); // first index = > 0 !
 
  int s = 0;
  for (int e = 0; e < nElem; ++e)
    {
      for (int j = 0; j < maxDeg; ++j)
        {
          const int f = ef(e, j);
          if (f < 0)
            break;
 
          econ.push_back(static_cast<cgsize_t>(f + 1 + decal));
          ++s;
        }
      eoff.push_back(s);
    }
 
  // XXX Elie Saikali ...
  // we need this to avoid the following warning
  // reading zone "Zone_0002"
  // reading element set "NGON_n"
  // reading element set "NFACE_n"
  // ERROR:  duplicate positive faces indices detected in NFace_n Elements connectivity
  std::unordered_set<cgsize_t> seen;
  for (auto& itr : econ)
    {
      if (seen.find(itr) != seen.end())
        itr *= -1; // already seen -> times -1 !!!
      else
        seen.insert(itr);
    }
 
  return ef.dimension(0);
}
 
int TRUST_2_CGNS::convert_connectivity_ngon(std::vector<cgsize_t>& econ, std::vector<cgsize_t>& eoff, const bool is_polyedre, int decal)
{
  assert (dom_trust_);
  if (is_polyedre)
    {
      Domaine_dis_base* domaine_dis = nullptr;
      Domaine_VF* vf = nullptr;
      get_domaine_dis_vf_if_poly(domaine_dis, vf);
 
      const IntTab& fs = vf ? (*vf).face_sommets() : fs_dual_.valeur();
 
      const int nFace = fs.dimension(0), maxDeg = fs.dimension(1);
 
      econ.clear(), eoff.clear();
 
      econ.reserve(static_cast<size_t>(nFace) * maxDeg);
      eoff.reserve(static_cast<size_t>(nFace) + 1);
 
      eoff.push_back(0); // first index = > 0 !
      int s = 0;
      for (int f = 0; f < nFace; ++f)
        {
          for (int j = 0; j < maxDeg; ++j)
            {
              const int v = fs(f, j);
              if (v < 0)
                break;
 
              econ.push_back(static_cast<cgsize_t>(v + 1 + decal));
              ++s;
            }
          eoff.push_back(s);
        }
 
      return fs.dimension(0);
    }
  else // POLYGONE
    {
      const IntTab& les_elems = dom_trust_->les_elems();
 
      const int nElem = les_elems.dimension(0), maxDeg = les_elems.dimension(1);
 
      econ.clear(), eoff.clear();
 
      econ.reserve(static_cast<size_t>(nElem) * maxDeg);
      eoff.reserve(static_cast<size_t>(nElem) + 1);
 
      eoff.push_back(0); // first index = > 0 !
      int s = 0;
      for (int e = 0; e < nElem; ++e)
        {
          for (int j = 0; j < maxDeg; ++j)
            {
              const int v = les_elems(e, j);
              if (v < 0)
                break;
              econ.push_back(static_cast<cgsize_t>(v + 1 + decal));
              ++s;
            }
          eoff.push_back(s);
        }
 
      return les_elems.dimension(0);
    }
}
 
#endif /* HAS_CGNS */