Reorder_Mesh.h

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#ifndef Reorder_Mesh_included
#define Reorder_Mesh_included
 
#include <TRUSTTabs_forward.h>
#include <Objet_U.h>
#include <Entree.h>
#include <Domaine.h>
 
/**! @brief Various methods of reordering Morton / Hilbert
 * See wiki: https://en.wikipedia.org/wiki/Z-order_curve
 */
enum class Reorder_Algo { None, Morton, Hilbert };
 
/**! @brief Reorder_Mesh allows the user to trigger the renumbering of the mesh entities.
 *
 * Renumbering can be done according to a Morton or Hilbert scheme (see Morton curve or Hilbert
 * curves on Wikipedia) thus improving the data co-localisation, in the following sense:
 *
 * - when iterating through the faces of the mesh
 * - and then retrieving the adjacent elements (indirection via face_voisin typically)
 * - ensures that the elements that are thus scanned are themselves not too wide spread in memory
 *
 * This helps improving memory access performance.
 * See .cpp file for more explanations on how this works.
 *
 * This object is used as a discretisation option - see class Discret_Thyd, member reorder_
 */
class Reorder_Mesh: public Objet_U
{
  Declare_instanciable(Reorder_Mesh);
 
public:
  template<typename _SIZE_>
  void reorder_domain(Domaine_32_64<_SIZE_>& dom) const;
 
  template<typename _SIZE_>
  void compute_renumbering(const DoubleTab_T<_SIZE_>& points, ArrOfInt_T<_SIZE_>& renum) const;
 
  template<typename _SIZE_>
  void dump_to_file(const DoubleTab_T<_SIZE_>& points, const std::string& filename) const;
 
  // Accessors
  Reorder_Algo algo() const { return algo_; }
  bool skip_nodes() const { return no_nodes_; }
  bool skip_elems() const { return no_elems_; }
  bool skip_faces() const { return no_faces_; }
  bool is_dump() const { return dump_; }
 
protected:
 
  Reorder_Algo algo_ = Reorder_Algo::None;  ///< Reordering algorithm
  bool no_nodes_ = false;                   ///< Whether to skip vertices in reordering
  bool no_elems_ = false;                   ///< Whether to skip elements in reordering
  bool no_faces_ = false;                   ///< Whether to skip faces in reordering
  bool dump_ = false;                       ///< Whether to dump previous and new positions into text files.
};
 
 
#endif