特徴線のある表面メッシュからテトラメッシュ作成(CGALライブラリ)

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78

 
 
 
 
 
 
 
 
 
-
!
 
 
-
!
 
 
 
-
!
 
-
!
 
 
-
!
 
 
 
-
!
 
-
!
 
 
-
-
!
|
-
!
|
-
!
|
|
-
!
|
|
|
|
-
!
-
!
|
|
|
|
|
-
|
|
!
|
|
|
|
|
|
|
|
|
!
 

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 
#include <CGAL/Mesh_triangulation_3.h>
#include <CGAL/Mesh_complex_3_in_triangulation_3.h>
#include <CGAL/Mesh_criteria_3.h>
 
#include <CGAL/Polyhedral_mesh_domain_with_features_3.h>
#include <CGAL/make_mesh_3.h>
 
// IO
#include <CGAL/IO/Polyhedron_iostream.h>
#include <CGAL/IO/Complex_3_in_triangulation_3_to_vtk.h>
 
// VTK
#include <vtkSmartPointer.h>
#include <vtkUnstructuredGrid.h>
#include <vtkXMLUnstructuredGridWriter.h>
 
// STL
#include <string>
 
// Domain 
typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
typedef CGAL::Polyhedral_mesh_domain_with_features_3<K> Mesh_domain;
 
// Triangulation
typedef CGAL::Mesh_triangulation_3<Mesh_domain>::type Tr;
typedef CGAL::Mesh_complex_3_in_triangulation_3<
  Tr,Mesh_domain::Corner_index,Mesh_domain::Curve_segment_index> C3t3;
 
// Criteria
typedef CGAL::Mesh_criteria_3<Tr> Mesh_criteria;
 
// To avoid verbose function and named parameters call
using namespace CGAL::parameters;
 
int main()
{
  // Create domain
  Mesh_domain domain("data/mesh.off");
  
  // Get sharp features
  domain.detect_features();
 
  // Mesh criteria
  Mesh_criteria criteria(facet_angle=25, facet_size=0.3, edge_size=0.3, facet_distance=0.1,
                         cell_radius_edge_ratio=3);
  
  // Mesh generation
  C3t3 c3t3 = CGAL::make_mesh_3<C3t3>(domain, criteria,
                                      lloyd(time_limit=30),
                                      no_exude(),
                                      perturb(sliver_bound=10, time_limit=15));
 
  // Set tetrahedron size (keep cell_radius_edge_ratio), ignore facets
  Mesh_criteria new_criteria(cell_radius_edge_ratio=3, cell_size=0.4);
  // Mesh refinement
  CGAL::refine_mesh_3(c3t3, domain, new_criteria);
 
 
  CGAL::perturb_mesh_3(c3t3, domain, time_limit=15);
 
 
  // Output
  //std::ofstream medit_file("out.mesh");
  //c3t3.output_to_medit(medit_file);
 
  vtkSmartPointer<vtkUnstructuredGrid> output =
    vtkSmartPointer<vtkUnstructuredGrid>::New();
  CGAL::output_c3t3_to_vtk_unstructured_grid(c3t3, output);
 
  vtkSmartPointer<vtkXMLUnstructuredGridWriter> writer =
    vtkSmartPointer<vtkXMLUnstructuredGridWriter>::New();
  writer->SetFileName("out.vtu");
  writer->SetInputData(output);
  writer->Update();
}