SurfaceElementSet Class Reference

A group of surface elements wrapped for point-containment / distance queries. More...

#include <SurfaceElementSet.h>

Public Member Functions
const std::vector< std::unique_ptr< SurfaceElement > > &	elements () const
	Owned surface-element wrappers, one per input element (input order preserved).
const std::vector< Point > &	centroids () const
	Per-element centroids (vertex averages), aligned index-for-index with elements().
const libMesh::BoundingBox &	boundingBox () const
	Global AABB of the group (plain union of element loose bounding boxes).
std::size_t	size () const
	Number of surface elements in the group.

Static Public Member Functions
static SurfaceElementSet	fromMesh (const MeshBase &mesh)
	Build a set from every active element of a surface mesh.
static SurfaceElementSet	fromElements (const std::vector< const Elem * > &elems)
	Build a set from a caller-provided subset of surface elements.

Private Member Functions
	SurfaceElementSet ()=default
	Built only through the factories.
void	addElement (const Elem *elem)
	Validate, wrap, and append a single element, growing centroids and the AABB.

Private Attributes
std::vector< std::unique_ptr< SurfaceElement > >	_elements
std::vector< Point >	_centroids
libMesh::BoundingBox	_bounding_box

Detailed Description

A group of surface elements wrapped for point-containment / distance queries.

This is the single place where a libMesh surface mesh (or a subset of its elements) is turned into SurfaceElement wrappers. It owns the wrappers, the matching per-element centroids, and the global axis-aligned bounding box (AABB) of the group. The AABB is method-independent: it is the plain union of the elements' loose bounding boxes with no algorithm-specific inflation.

Construct via the factories:

• fromMesh(mesh) : wrap every active element of a whole surface mesh.
• fromElements(elems) : wrap a caller-provided subset of elements (e.g. one subdomain group).

The referenced elements must outlive this object.

Definition at line 35 of file SurfaceElementSet.h.

Constructor & Destructor Documentation

SurfaceElementSet()

SurfaceElementSet::SurfaceElementSet ( )

privatedefault

Built only through the factories.

Member Function Documentation

addElement()

void SurfaceElementSet::addElement ( const Elem *  elem )

private

Validate, wrap, and append a single element, growing centroids and the AABB.

All elements must share one supported type (EDGE2 or TRI3).

Definition at line 47 of file SurfaceElementSet.C.

{
  mooseAssert(elem, "Element must not be null");
 
  // Enforce a homogeneous element family: every element must share the type of
  // the first one added, so a group never mixes 2D EDGE2 and 3D TRI3 faces.
  if (!_elements.empty() && _elements.front()->elem().type() != elem->type())
    mooseError("SurfaceElementSet: mixed element types are not supported (found ",
               libMesh::Utility::enum_to_string(elem->type()),
               " after ",
               libMesh::Utility::enum_to_string(_elements.front()->elem().type()),
               ").");
 
  std::unique_ptr<SurfaceElement> surface_elem;
  if (elem->type() == EDGE2)
    surface_elem = std::make_unique<SurfaceEdge2>(elem);
  else if (elem->type() == TRI3)
    surface_elem = std::make_unique<SurfaceTri3>(elem);
  else
    mooseError("SurfaceElementSet: unsupported element type ",
               libMesh::Utility::enum_to_string(elem->type()),
               ". Only EDGE2 (2D) and TRI3 (3D) surface elements are supported.");
 
  // Grow the AABB; initialize it from the first element so an empty union does
  // not leave the box in libMesh's inverted default state.
  const auto bbox = elem->loose_bounding_box();
  if (_elements.empty())
    _bounding_box = bbox;
  else
    _bounding_box.union_with(bbox);
 
  _centroids.emplace_back(elem->vertex_average());
  _elements.emplace_back(std::move(surface_elem));
}

Referenced by fromElements(), and fromMesh().

boundingBox()

const libMesh::BoundingBox & SurfaceElementSet::boundingBox ( ) const

inline

Global AABB of the group (plain union of element loose bounding boxes).

Definition at line 51 of file SurfaceElementSet.h.

{ return _bounding_box; }

centroids()

const std::vector< Point > & SurfaceElementSet::centroids ( ) const

inline

Per-element centroids (vertex averages), aligned index-for-index with elements().

Definition at line 48 of file SurfaceElementSet.h.

{ return _centroids; }

elements()

const std::vector< std::unique_ptr< SurfaceElement > > & SurfaceElementSet::elements ( ) const

inline

Owned surface-element wrappers, one per input element (input order preserved).

Definition at line 45 of file SurfaceElementSet.h.

{ return _elements; }

fromElements()

SurfaceElementSet SurfaceElementSet::fromElements ( const std::vector< const Elem * > &  elems )

static

Build a set from a caller-provided subset of surface elements.

Definition at line 33 of file SurfaceElementSet.C.

{
  SurfaceElementSet set;
 
  set._elements.reserve(elems.size());
  set._centroids.reserve(elems.size());
 
  for (const auto * elem : elems)
    set.addElement(elem);
 
  return set;
}

fromMesh()

SurfaceElementSet SurfaceElementSet::fromMesh ( const MeshBase &  mesh )

static

Build a set from every active element of a surface mesh.

Definition at line 18 of file SurfaceElementSet.C.

{
  SurfaceElementSet set;
 
  const auto n = mesh.n_active_elem();
  set._elements.reserve(n);
  set._centroids.reserve(n);
 
  for (const auto * elem : mesh.active_element_ptr_range())
    set.addElement(elem);
 
  return set;
}

Referenced by BoundaryMeshBuilder::buildDefaultSet().

size()

std::size_t SurfaceElementSet::size ( ) const

inline

Number of surface elements in the group.

Definition at line 54 of file SurfaceElementSet.h.

{ return _elements.size(); }

Member Data Documentation

_bounding_box

libMesh::BoundingBox SurfaceElementSet::_bounding_box

private

Definition at line 66 of file SurfaceElementSet.h.

Referenced by addElement(), and boundingBox().

_centroids

std::vector<Point> SurfaceElementSet::_centroids

private

Definition at line 65 of file SurfaceElementSet.h.

Referenced by addElement(), centroids(), fromElements(), and fromMesh().

_elements

std::vector<std::unique_ptr<SurfaceElement> > SurfaceElementSet::_elements

private

Definition at line 64 of file SurfaceElementSet.h.

Referenced by addElement(), elements(), fromElements(), fromMesh(), and size().

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

• include/utils/SurfaceElementSet.h
• src/utils/SurfaceElementSet.C