SphereSurfaceMeshGenerator Class Reference

Create a sphere surface mesh based on the recursive subdivision of the faces of a regular icosahedron. More...

#include <SphereSurfaceMeshGenerator.h>

Inheritance diagram for SphereSurfaceMeshGenerator:

Public Member Functions
	SphereSurfaceMeshGenerator (const InputParameters &parameters)
std::unique_ptr< MeshBase >	generate () override

Protected Attributes
const Real	_radius
	sphere radius More...
const Point	_center
const unsigned int	_depth
	recursion levels for triangle subdivision More...

Detailed Description

Create a sphere surface mesh based on the recursive subdivision of the faces of a regular icosahedron.

Definition at line 25 of file SphereSurfaceMeshGenerator.h.

Constructor & Destructor Documentation

SphereSurfaceMeshGenerator()

SphereSurfaceMeshGenerator::SphereSurfaceMeshGenerator

(

const InputParameters &

parameters

)

Definition at line 37 of file SphereSurfaceMeshGenerator.C.

  : MeshGenerator(parameters),
    _radius(getParam<Real>("radius")),
    _center(getParam<Point>("center")),
    _depth(getParam<unsigned int>("depth"))
{
}

Member Function Documentation

generate()

std::unique_ptr< MeshBase > SphereSurfaceMeshGenerator::generate ( )

override

Definition at line 46 of file SphereSurfaceMeshGenerator.C.

{
  // Have MOOSE construct the correct libMesh::Mesh object using Mesh block and CLI parameters.
  auto mesh = _mesh->buildMeshBaseObject();
  mesh->set_mesh_dimension(2);
  mesh->set_spatial_dimension(3);

  const Sphere sphere(_center, _radius);

  // icosahedron points (using golden ratio rectangle construction)
  const Real phi = (1.0 + std::sqrt(5.0)) / 2.0;
  const Real X = std::sqrt(1.0 / (phi * phi + 1.0));
  const Real Z = X * phi;
  const Point vdata[12] = {{-X, 0.0, Z},
                           {X, 0.0, Z},
                           {-X, 0.0, -Z},
                           {X, 0.0, -Z},
                           {0.0, Z, X},
                           {0.0, Z, -X},
                           {0.0, -Z, X},
                           {0.0, -Z, -X},
                           {Z, X, 0.0},
                           {-Z, X, 0.0},
                           {Z, -X, 0.0},
                           {-Z, -X, 0.0}};
  for (unsigned int i = 0; i < 12; ++i)
    mesh->add_point(vdata[i] * _radius + _center, i);

  // icosahedron faces
  const unsigned int tindices[20][3] = {{0, 4, 1},  {0, 9, 4},  {9, 5, 4},  {4, 5, 8},  {4, 8, 1},
                                        {8, 10, 1}, {8, 3, 10}, {5, 3, 8},  {5, 2, 3},  {2, 7, 3},
                                        {7, 10, 3}, {7, 6, 10}, {7, 11, 6}, {11, 0, 6}, {0, 1, 6},
                                        {6, 1, 10}, {9, 0, 11}, {9, 11, 2}, {9, 2, 5},  {7, 2, 11}};
  for (unsigned int i = 0; i < 20; ++i)
  {
    Elem * elem = mesh->add_elem(new Tri3);
    elem->set_node(0) = mesh->node_ptr(tindices[i][0]);
    elem->set_node(1) = mesh->node_ptr(tindices[i][1]);
    elem->set_node(2) = mesh->node_ptr(tindices[i][2]);
  }

  // we need to prepare distributed meshes before using refinement
  if (!mesh->is_replicated())
    mesh->prepare_for_use(/*skip_renumber =*/false);

  // Now we have the beginnings of a sphere.
  // Add some more elements by doing uniform refinements and
  // popping nodes to the boundary.
  MeshRefinement mesh_refinement(*mesh);

  // Loop over the elements, refine, pop nodes to boundary.
  for (unsigned int r = 0; r < _depth; ++r)
  {
    mesh_refinement.uniformly_refine(1);

    auto it = mesh->active_nodes_begin();
    const auto end = mesh->active_nodes_end();

    for (; it != end; ++it)
    {
      Node & node = **it;
      node = sphere.closest_point(node);
    }
  }

  // Flatten the AMR mesh to get rid of inactive elements
  MeshTools::Modification::flatten(*mesh);

  return dynamic_pointer_cast<MeshBase>(mesh);
}

Member Data Documentation

_center

const Point SphereSurfaceMeshGenerator::_center

protected

Definition at line 37 of file SphereSurfaceMeshGenerator.h.

Referenced by generate().

_depth

const unsigned int SphereSurfaceMeshGenerator::_depth

protected

recursion levels for triangle subdivision

Definition at line 40 of file SphereSurfaceMeshGenerator.h.

Referenced by generate().

_radius

const Real SphereSurfaceMeshGenerator::_radius

protected

sphere radius

Definition at line 34 of file SphereSurfaceMeshGenerator.h.

Referenced by generate().

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The documentation for this class was generated from the following files:

• phase_field/include/meshgenerators/SphereSurfaceMeshGenerator.h
• phase_field/src/meshgenerators/SphereSurfaceMeshGenerator.C