C++ MeshBase::get_boundary_info方法代码示例

void
SideSetsGeneratorBase::flood(const Elem * elem,
                             Point normal,
                             boundary_id_type side_id,
                             MeshBase & mesh)
{
  if (elem == nullptr || (_visited[side_id].find(elem) != _visited[side_id].end()))
    return;

  _visited[side_id].insert(elem);
  for (unsigned int side = 0; side < elem->n_sides(); ++side)
  {
    if (elem->neighbor_ptr(side))
      continue;

    _fe_face->reinit(elem, side);
    const std::vector<Point> normals = _fe_face->get_normals();

    // We'll just use the normal of the first qp
    if (std::abs(1.0 - normal * normals[0]) <= _variance)
    {
      mesh.get_boundary_info().add_side(elem, side, side_id);
      for (unsigned int neighbor = 0; neighbor < elem->n_sides(); ++neighbor)
      {
        // Flood to the neighboring elements using the current matching side normal from this
        // element.
        // This will allow us to tolerate small changes in the normals so we can "paint" around a
        // curve.
        flood(elem->neighbor_ptr(neighbor), _fixed_normal ? normal : normals[0], side_id, mesh);
      }
    }
  }
}

void
MeshExtruderGenerator::changeID(MeshBase & mesh,
                                const std::vector<BoundaryName> & names,
                                BoundaryID old_id)
{
  std::vector<boundary_id_type> boundary_ids = MooseMeshUtils::getBoundaryIDs(mesh, names, true);

  if (std::find(boundary_ids.begin(), boundary_ids.end(), old_id) == boundary_ids.end())
    MooseMeshUtils::changeBoundaryId(mesh, old_id, boundary_ids[0], true);

  for (unsigned int i = 0; i < boundary_ids.size(); ++i)
  {
    mesh.get_boundary_info().sideset_name(boundary_ids[i]) = names[i];
    mesh.get_boundary_info().nodeset_name(boundary_ids[i]) = names[i];
  }
}

void MeshTools::Subdivision::all_subdivision(MeshBase & mesh)
{
  std::vector<Elem *> new_elements;
  new_elements.reserve(mesh.n_elem());
  const bool mesh_has_boundary_data =
    (mesh.get_boundary_info().n_boundary_ids() > 0);

  std::vector<Elem *> new_boundary_elements;
  std::vector<short int> new_boundary_sides;
  std::vector<boundary_id_type> new_boundary_ids;

  MeshBase::const_element_iterator       el     = mesh.elements_begin();
  const MeshBase::const_element_iterator end_el = mesh.elements_end();
  for (; el != end_el; ++el)
    {
      const Elem * elem = *el;
      libmesh_assert_equal_to(elem->type(), TRI3);

      Elem * tri = new Tri3Subdivision;
      tri->set_id(elem->id());
      tri->subdomain_id() = elem->subdomain_id();
      tri->set_node(0) = (*el)->get_node(0);
      tri->set_node(1) = (*el)->get_node(1);
      tri->set_node(2) = (*el)->get_node(2);

      if (mesh_has_boundary_data)
        {
          for (unsigned short side = 0; side < elem->n_sides(); ++side)
            {
              const boundary_id_type boundary_id =
                mesh.get_boundary_info().boundary_id(elem, side);
              if (boundary_id != BoundaryInfo::invalid_id)
                {
                  // add the boundary id to the list of new boundary ids
                  new_boundary_ids.push_back(boundary_id);
                  new_boundary_elements.push_back(tri);
                  new_boundary_sides.push_back(side);
                }
            }

          // remove the original element from the BoundaryInfo structure
          mesh.get_boundary_info().remove(elem);
        }

      new_elements.push_back(tri);
      mesh.insert_elem(tri);
    }
  mesh.prepare_for_use();

  if (mesh_has_boundary_data)
    {
      // If the old mesh had boundary data, the new mesh better have some too.
      libmesh_assert_greater(new_boundary_elements.size(), 0);

      // We should also be sure that the lengths of the new boundary data vectors
      // are all the same.
      libmesh_assert_equal_to(new_boundary_sides.size(), new_boundary_elements.size());
      libmesh_assert_equal_to(new_boundary_sides.size(), new_boundary_ids.size());

      // Add the new boundary info to the mesh.
      for (unsigned int s = 0; s < new_boundary_elements.size(); ++s)
        mesh.get_boundary_info().add_side(new_boundary_elements[s],
                                          new_boundary_sides[s],
                                          new_boundary_ids[s]);
    }

  mesh.prepare_for_use();
}

void MeshTools::Subdivision::add_boundary_ghosts(MeshBase & mesh)
{
  static const Real tol = 1e-5;

  // add the mirrored ghost elements (without using iterators, because the mesh is modified in the course)
  std::vector<Tri3Subdivision *> ghost_elems;
  std::vector<Node *> ghost_nodes;
  const unsigned int n_elem = mesh.n_elem();
  for (unsigned int eid = 0; eid < n_elem; ++eid)
    {
      Elem * elem = mesh.elem(eid);
      libmesh_assert_equal_to(elem->type(), TRI3SUBDIVISION);

      // If the triangle happens to be in a corner (two boundary
      // edges), we perform a counter-clockwise loop by mirroring the
      // previous triangle until we come back to the original
      // triangle.  This prevents degenerated triangles in the mesh
      // corners and guarantees that the node in the middle of the
      // loop is of valence=6.
      for (unsigned int i = 0; i < elem->n_sides(); ++i)
        {
          libmesh_assert_not_equal_to(elem->neighbor(i), elem);

          if (elem->neighbor(i) == libmesh_nullptr &&
              elem->neighbor(next[i]) == libmesh_nullptr)
            {
              Elem * nelem = elem;
              unsigned int k = i;
              for (unsigned int l=0;l<4;l++)
                {
                  // this is the vertex to be mirrored
                  Point point = nelem->point(k) + nelem->point(next[k]) - nelem->point(prev[k]);

                  // Check if the proposed vertex doesn't coincide
                  // with one of the existing vertices.  This is
                  // necessary because for some triangulations, it can
                  // happen that two mirrored ghost vertices coincide,
                  // which would then lead to a zero size ghost
                  // element below.
                  Node * node = libmesh_nullptr;
                  for (unsigned int j = 0; j < ghost_nodes.size(); ++j)
                    {
                      if ((*ghost_nodes[j] - point).size() < tol * (elem->point(k) - point).size())
                        {
                          node = ghost_nodes[j];
                          break;
                        }
                    }

                  // add the new vertex only if no other is nearby
                  if (node == libmesh_nullptr)
                    {
                      node = mesh.add_point(point);
                      ghost_nodes.push_back(node);
                    }

                  Tri3Subdivision * newelem = new Tri3Subdivision();

                  // add the first new ghost element to the list just as in the non-corner case
                  if (l == 0)
                    ghost_elems.push_back(newelem);

                  newelem->set_node(0) = nelem->get_node(next[k]);
                  newelem->set_node(1) = nelem->get_node(k);
                  newelem->set_node(2) = node;
                  newelem->set_neighbor(0, nelem);
                  newelem->set_ghost(true);
                  if (l>0)
                    newelem->set_neighbor(2, libmesh_nullptr);
                  nelem->set_neighbor(k, newelem);

                  mesh.add_elem(newelem);
                  mesh.get_boundary_info().add_node(nelem->get_node(k), 1);
                  mesh.get_boundary_info().add_node(nelem->get_node(next[k]), 1);
                  mesh.get_boundary_info().add_node(nelem->get_node(prev[k]), 1);
                  mesh.get_boundary_info().add_node(node, 1);

                  nelem = newelem;
                  k = 2 ;
                }

              Tri3Subdivision * newelem = new Tri3Subdivision();

              newelem->set_node(0) = elem->get_node(next[i]);
              newelem->set_node(1) = nelem->get_node(2);
              newelem->set_node(2) = elem->get_node(prev[i]);
              newelem->set_neighbor(0, nelem);
              nelem->set_neighbor(2, newelem);
              newelem->set_ghost(true);
              newelem->set_neighbor(2, elem);
              elem->set_neighbor(next[i],newelem);

              mesh.add_elem(newelem);

              break;
            }
        }

      for (unsigned int i = 0; i < elem->n_sides(); ++i)
        {
//.........这里部分代码省略.........