getfem_mesh_im_level_set.h

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/* -*- c++ -*- (enables emacs c++ mode) */
/*===========================================================================
 
 Copyright (C) 2005-2026 Yves Renard
 
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/**@file getfem_mesh_im_level_set.h
   @author  Yves Renard <[email protected]>
   @date February 02, 2005.
   @brief a subclass of mesh_im which is conformal to a number of level sets.
*/
 
#ifndef GETFEM_MESH_IM_LEVEL_SET_H__
#define GETFEM_MESH_IM_LEVEL_SET_H__
 
#include "getfem_mesh_im.h"
#include "getfem_mesh_level_set.h"
#include <set>
 
namespace getfem {
 
  /** 
     Describe an adaptable integration method linked to a mesh cut by
     a level set.  It is possible to choose to integrate over the
     whole mesh, or to select integration on the "inside" (the
     intersection of the negative parts of the levelsets, or any other
     union, intersection etc of the levelset negative parts), the
     "outside", or just the levelset boundary.
  */
 
  class mesh_im_level_set : public mesh_im {
  protected :
    pintegration_method regular_simplex_pim;
    pintegration_method base_singular_pim;
    mesh_level_set *mls;
 
    mesh_im cut_im; /* stores an im only for convexes who are crossed
                       by a levelset */
 
    dal::bit_vector ignored_im; /* convex list whose integration method is
                                   ignored (for instance because
                                   INTEGRATE_INSIDE and the convex
                                   is outside etc.) */
    std::vector<pintegration_method> build_methods;
 
    mutable bool is_adapted;
    int integrate_where; // INTEGRATE_INSIDE or INTEGRATE_OUTSIDE
 
    void clear_build_methods();
    void build_method_of_convex(size_type cv);
 
    /* CSG (constructive solid geometry) description for the
       definition of the domain with respect to one or more levelsets.
    */
    std::string ls_csg_description;
  public:
    struct bool2 {
      bool in;      // true when the point in inside the levelsets 
      unsigned bin; /* 0 when the point is not on the boundary, and
                       (lsindex+1) when it is on the boundary of the
                       lsindex-th levelset */
    };
  protected:
    /* return true when the point is inside the levelsets CSG
       description */
    bool2 is_point_in_selected_area
    (const std::vector<pmesher_signed_distance> &mesherls0,
     const std::vector<pmesher_signed_distance> &mesherls1, const base_node& P);
    bool2 is_point_in_selected_area2
    (const std::vector<pmesher_signed_distance> &mesherls0,
     const std::vector<pmesher_signed_distance> &mesherls1, const base_node& P);
 
  public :
    enum { INTEGRATE_INSIDE = 1, INTEGRATE_OUTSIDE = 2, INTEGRATE_ALL = 2+1,
           INTEGRATE_BOUNDARY = 4};
    void update_from_context(void) const;
    
    /** Apply the adequate integration methods. */
    void adapt(void);
    void clear(void); // to be modified
 
    /** Set the specific integration methods. see the constructor
        documentation for more details. */
    void set_simplex_im(pintegration_method reg,
                        pintegration_method sing = 0) {
      regular_simplex_pim = reg;
      base_singular_pim = sing;
    }
 
    int location() const { return integrate_where; }
    
    size_type memsize() const {
      return mesh_im::memsize(); // + ... ;
    }
 
    void init_with_mls(mesh_level_set &me, 
                       int integrate_where_ = INTEGRATE_ALL,
                       pintegration_method reg = 0,
                       pintegration_method sing = 0);
 
    /** 
        @param me the level-set.
        
        @param integrate_where : choose between INTEGRATE_ALL,
        INTEGRATE_BOUNDARY, INTEGRATE_INSIDE and INTEGRATE_OUTSIDE.
 
        @param reg the integration method (for simplices) that will be
        used on the sub-simplices of convexes crossed by the levelset.
 
        @param sing the (optional) integration method to use on the crack tips
        (i.e. when the levelset has a secondary level set), this is
        generally an IM_QUASI_POLAR method as it provides a good
        integration of singular XFEM functions.
    */
    mesh_im_level_set(mesh_level_set &me, 
                      int integrate_where_ = INTEGRATE_ALL,
                      pintegration_method reg = 0,
                      pintegration_method sing = 0);
    mesh_im_level_set(void);
 
    virtual pintegration_method int_method_of_element(size_type cv) 
      const;
    ~mesh_im_level_set() { clear_build_methods(); }
 
 
    /**
       Set the boolean operation which define the integration domain
       when there is more than one levelset.
 
       the syntax is very simple, for example if there are 3 different
       levelset,
       
       "a*b*c" is the intersection of the domains defined by each
       levelset (this is the default behaviour if this function is not
       called).
 
       "a+b+c" is the union of their domains.
 
       "c-(a+b)" is the domain of the third levelset minus the union of
       the domains of the two others.
       
       "!a" is the complementary of the domain of a (i.e. it is the
       domain where a(x)>0)
 
       The first levelset is always referred to with "a", the second
       with "b", and so on..
    */
    void set_level_set_boolean_operations(const std::string description) {
      ls_csg_description = description;
    }
    void compute_normal_vector(const fem_interpolation_context &ctx,
                               base_small_vector &vec) const;
  };
 
 
 
  /** 
     Describe an adaptable integration method linked to a mesh cut by at
     least two level sets on the intersection of two level sets.
  */
  class mesh_im_cross_level_set : public mesh_im {
  protected :
    pintegration_method segment_pim;
    mesh_level_set *mls;
 
    mesh_im cut_im; /* stores an im only for convexes who are crossed
                       by a levelset */
 
    dal::bit_vector ignored_im; /* convex list whose integration method is
                                   ignored (for instance because
                                   INTEGRATE_INSIDE and the convex
                                   is outside etc.) */
    std::vector<pintegration_method> build_methods;
 
    mutable bool is_adapted;
    size_type ind_ls1, ind_ls2;
 
    void clear_build_methods();
    void build_method_of_convex(size_type cv, mesh &global_intersection,
                                bgeot::rtree &rtree_seg);
 
  public:
 
    enum { INTEGRATE_INSIDE = 1, INTEGRATE_OUTSIDE = 2, INTEGRATE_ALL = 2+1,
           INTEGRATE_BOUNDARY = 4};
    void update_from_context(void) const;
    
    /** Apply the adequate integration methods. */
    void adapt(void);
    void clear(void); // to be modified
 
    /** Set the specific integration methods. see the constructor
        documentation for more details. */
    void set_segment_im(pintegration_method pim)
    { segment_pim = pim; }
    
    size_type memsize() const {
      return mesh_im::memsize(); // + ... ;
    }
 
    void init_with_mls(mesh_level_set &me, 
                       size_type ind_ls1_, size_type ind_ls2_,
                       pintegration_method pim = 0);
 
    mesh_im_cross_level_set(mesh_level_set &me, 
                            size_type ind_ls1_, size_type ind_ls2_,
                            pintegration_method pim = 0);
    mesh_im_cross_level_set(void);
 
    virtual pintegration_method int_method_of_element(size_type cv) 
      const;
    ~mesh_im_cross_level_set() { clear_build_methods(); }
 
  };
 
 
 
 
 
 
  
}  /* end of namespace getfem.                                             */
 
 
#endif /* GETFEM_MESH_IM_LEVEL_SET_H__  */