getfem_regular_meshes.h

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/* -*- c++ -*- (enables emacs c++ mode) */
/*===========================================================================

 Copyright (C) 1999-2017 Yves Renard

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/**@file getfem_regular_meshes.h
   @author  Yves Renard <Yves.Renard@insa-lyon.fr>
   @date December 20, 1999.
   @brief Build regular meshes.
*/
#ifndef GETFEM_REGULAR_MESHES_H__
#define GETFEM_REGULAR_MESHES_H__

#include "getfem_mesh.h"

namespace getfem
{
  /* ******************************************************************** */
  /*        Generation de maillages reguliers de simplexes.               */
  /* ******************************************************************** */

  /* ******************************************************************** */
  /* ajoute au maillage "me" un maillage regulier de dimension "N"        */
  /* a partir du point "org" defini par les parallelepipedes engendres    */
  /* par la liste des vecteurs "vect". La liste iref est une liste        */
  /* d'entiers correspondant au nombre de parallelepidedes sur chaque     */
  /* dimension. Chaque parallelepidede est simplexifie.                   */
  /* ******************************************************************** */

  void parallelepiped_regular_simplex_mesh_(mesh &me, dim_type N,
    const base_node &org, const base_small_vector *ivect, const size_type *iref);

  template<class ITER1, class ITER2>
    void parallelepiped_regular_simplex_mesh(mesh &me,
                                             dim_type N,
             const base_node &org, ITER1 ivect, ITER2 iref)
  { 
    std::vector<base_small_vector> vect(N);
    std::copy(ivect, ivect+N, vect.begin());
    std::vector<size_type> ref(N);
    std::copy(iref, iref+N, ref.begin());
    parallelepiped_regular_simplex_mesh_(me, N, org, &(vect[0]),
                                         &(ref[0]));
  } 

  void parallelepiped_regular_prism_mesh_(mesh &me, dim_type N,
      const base_node &org, const base_small_vector *ivect, const size_type *iref);

  template<class ITER1, class ITER2>
    void parallelepiped_regular_prism_mesh(mesh &me,
                                             dim_type N,
             const base_node &org, ITER1 ivect, ITER2 iref)
  { 
    std::vector<base_small_vector> vect(N);
    std::copy(ivect, ivect+N, vect.begin());
    std::vector<size_type> ref(N);
    std::copy(iref, iref+N, ref.begin());
    parallelepiped_regular_prism_mesh_(me, N, org, &(vect[0]),
                                         &(ref[0]));
  } 

  void parallelepiped_regular_mesh_(mesh &me, dim_type N,
    const base_node &org, const base_small_vector *ivect, const size_type *iref, bool linear_gt);

  template<class ITER1, class ITER2>
    void parallelepiped_regular_mesh(mesh &me,
                                             dim_type N,
                                     const base_node &org, ITER1 ivect, ITER2 iref, bool linear_gt=false)
  { 
    std::vector<base_small_vector> vect(N);
    std::copy(ivect, ivect+N, vect.begin());
    std::vector<size_type> ref(N);
    std::copy(iref, iref+N, ref.begin());
    parallelepiped_regular_mesh_(me, N, org, &(vect[0]), &(ref[0]), linear_gt);
  } 

  void parallelepiped_regular_pyramid_mesh_(mesh &me, const base_node &org,
   const base_small_vector *ivect, const size_type *iref);

  template<class ITER1, class ITER2>
    void parallelepiped_regular_pyramid_mesh(mesh &me,
                                     const base_node &org, ITER1 ivect, ITER2 iref)
  { 
    int N=3;
    std::vector<base_small_vector> vect(N);
    std::copy(ivect, ivect+N, vect.begin());
    std::vector<size_type> ref(N);
    std::copy(iref, iref+N, ref.begin());
    parallelepiped_regular_pyramid_mesh_(me, org, &(vect[0]), &(ref[0]));
  } 


  /**
     Build a regular mesh of the unit square/cube/, etc.
     @param m the output mesh.

     @param pgt the geometric transformation to use. For example, use 
     @code
     pgt = geometric_trans_descriptor("GT_PK(2,1"); // to build a mesh of triangles
     pgt = geometric_trans_descriptor("QK(3,2)"); // to build a mesh of order 2 parallelepipeded
     @endcode

     @param nsubdiv is the number of cells in each direction.  

     @param noised if set, will cause the interior nodes to be randomly "shaken".
   */
  void regular_unit_mesh(mesh& m, std::vector<size_type> nsubdiv, 
                         bgeot::pgeometric_trans pgt, bool noised = false);

  /**
     Build a regular mesh parametrized by the string st.
     The format of st is the following
     std::string st("GT='GT_PK(2,1)'; NSUBDIV=[5,5]; ORG=[0,0]; SIZES=[1,1]; NOISED=0");
     where GT is the geometric transformation, NSUBDIV a vector of the number
     of subdivisions in each coordinate (default value 2), ORG is the origin
     of the mesh (default value [0,0,...]), SIZES is a vector of the sizes
     in each direction (default value [1, 1, ...] and if NOISED=1 the nodes
     of the interior of the mesh are randomly "shaken" (default value NOISED=0).
     All the parameters are optional but GT.

     @param m the output mesh.    
  */
  void regular_mesh(mesh& m, const std::string &st);

  /**
     Build a regular mesh on a ball, parametrized by the string st.
     The format of st is similar to getfem::regular_mesh.
     @see getfem::import_mesh.
     All parameters except the geometric transformation GT are optional.
     Here, parameter NSUBDIV has to be a vector of size 2 that holds the
     number of subdivisions in the core and the peel sub-regions of the mesh.
     SIZES is an one element vector that provides the ball radius
     (default radius is equal to 1).
     If NOISED=1 the nodes in the interior of the individual sub-regions
     of the mesh are randomly "shaken" (default value NOISED=0).
     An additional integer paramater called SYMMETRIES receiving the
     values 1, 2 or 3 (in three dimensions) permits to respectively request
     one half, one quarter or one sixteenth of the ball to be meshed
     (default value SYMMETRIES=0).

     @param m the output mesh.    
  */
  void regular_ball_mesh(mesh& m, const std::string &st);

}  /* end of namespace getfem.                                             */


#endif /* GETFEM_REGULAR_MESHES_H__  */