Describe a mesh (collection of convexes (elements) and points). More...

#include <getfem_mesh.h>

Inherits bgeot::basic_mesh, getfem::context_dependencies, dal::static_stored_object, and std::enable_shared_from_this< mesh >.

Inherited by getfem::global_mesh_for_mesh_level_set, getfem::mesh_cache_for_Bank_basic_refine_convex, getfem::mesh_cache_for_Bank_build_green_simplexes, and getfem::torus_mesh.

Public Member Functions
	mesh (const std::string name="")
	Constructor.

void	update_from_context () const
	this function has to be defined and should update the object when the context is modified.

ref_mesh_face_pt_ct	points_of_face_of_convex (size_type ic, short_type f) const
	Return a (pseudo)container of points of face of a given convex.

ref_convex	convex (size_type ic) const
	return a bgeot::convex object for the convex number ic.

size_type	nb_points () const
	Give the number of geometrical nodes in the mesh.

const dal::bit_vector &	points_index () const
	Return the points index.

void	sup_point (size_type i)
	Delete the point of index i from the mesh if it is not linked to a convex.

void	swap_points (size_type i, size_type j)
	Swap the indexes of points of index i and j in the whole structure.

size_type	search_point (const base_node &pt, const scalar_type radius=0) const
	Search a point given its coordinates. More...

gmm::uint64_type	convex_version_number (size_type ic) const
	return the version number of the convex ic.

template<class ITER >
size_type	add_convex (bgeot::pgeometric_trans pgt, ITER ipts)
	Add a convex to the mesh. More...

template<class ITER >
size_type	add_convex_by_points (bgeot::pgeometric_trans pgt, ITER ipts, const scalar_type tol=scalar_type(0))
	Add a convex to the mesh, given a geometric transformation and a list of point coordinates. More...

template<class ITER >
size_type	add_simplex (dim_type di, ITER ipts)
	Add a simplex to the mesh, given its dimension and point numbers.

template<class ITER >
size_type	add_simplex_by_points (dim_type dim, ITER ipts)
	Add a simplex to the mesh, given its dimension and point coordinates. More...

size_type	add_segment (size_type a, size_type b)
	Add a segment to the mesh, given the point id of its vertices.

size_type	add_segment_by_points (const base_node &pt1, const base_node &pt2)
	Add a segment to the mesh, given the coordinates of its vertices.

size_type	add_triangle (size_type a, size_type b, size_type c)
	Add a triangle to the mesh, given the point id of its vertices.

size_type	add_triangle_by_points (const base_node &p1, const base_node &p2, const base_node &p3)
	Add a triangle to the mesh, given the coordinates of its vertices.

size_type	add_tetrahedron (size_type a, size_type b, size_type c, size_type d)
	Add a tetrahedron to the mesh, given the point id of its vertices.

size_type	add_tetrahedron_by_points (const base_node &p1, const base_node &p2, const base_node &p3, const base_node &p4)
	Add a tetrahedron to the mesh, given the coordinates of its vertices.

size_type	add_pyramid (size_type a, size_type b, size_type c, size_type d, size_type e)
	Add a pyramid to the mesh, given the point id of its vertices.

template<class ITER >
size_type	add_parallelepiped (dim_type di, const ITER &ipts)
	Add a parallelepiped to the mesh. More...

template<class ITER >
size_type	add_parallelepiped_by_points (dim_type di, const ITER &ps)
	Add a parallelepiped to the mesh. More...

template<class ITER >
size_type	add_prism (dim_type di, const ITER &ipts)
	Add a prism to the mesh. More...

template<class ITER >
size_type	add_prism_by_points (dim_type di, const ITER &ps)
	Add a prism to the mesh. More...

void	merge_convexes_from_mesh (const mesh &m, size_type rg=size_type(-1), scalar_type tol=scalar_type(0))
	Merge all convexes from a another mesh, possibly restricted to a mesh region.

void	sup_convex (size_type ic, bool sup_points=false)
	Delete the convex of index ic from the mesh.

void	swap_convex (size_type i, size_type j)
	Swap the indexes of the convex of indexes i and j in the whole structure.

base_small_vector	normal_of_face_of_convex (size_type ic, short_type f, const base_node &pt) const
	Return the normal of the given convex face, evaluated at the point pt. More...

base_matrix	local_basis_of_face_of_convex (size_type ic, short_type f, const base_node &pt) const
	Return a local basis for the convex face. More...

base_matrix	local_basis_of_face_of_convex (size_type ic, short_type f, size_type n) const
	Return a local basis for the convex face. More...

scalar_type	convex_quality_estimate (size_type ic) const
	Return an estimate of the convex quality (0 <= Q <= 1).

scalar_type	convex_area_estimate (size_type ic, size_type degree=2) const
	Return an estimate of the convex area. More...

virtual scalar_type	convex_radius_estimate (size_type ic) const
	Return an estimate of the convex largest dimension. More...

scalar_type	minimal_convex_radius_estimate () const
	Return an estimate of the convex smallest dimension. More...

scalar_type	maximal_convex_radius_estimate () const
	Return an estimate of the convex largest dimension. More...

void	translation (const base_small_vector &)
	Apply the given translation to each mesh node.

void	transformation (const base_matrix &)
	apply the given matrix transformation to each mesh node.

void	bounding_box (base_node &Pmin, base_node &Pmax) const
	Return the bounding box [Pmin - Pmax] of the mesh.

const mesh_region	region (size_type id) const
	Return the region of index 'id'. More...

bool	has_region (size_type s) const
	Return true if the region of index 's' exists in the mesh.

void	sup_region (size_type b)
	Remove the region of index b.

void	sup_convex_from_regions (size_type cv)
	Remove all references to a convex from all regions stored in the mesh. More...

void	optimize_structure (bool with_renumbering=true)
	Pack the mesh : renumber convexes and nodes such that there is no holes in their numbering. More...

const std::vector< size_type > &	cuthill_mckee_ordering () const
	Return the list of convex IDs for a Cuthill-McKee ordering.

void	clear ()
	Erase the mesh.

void	write_to_file (const std::string &name) const
	Write the mesh to a file. More...

void	write_to_file (std::ostream &ost) const
	Write the mesh to a text stream. More...

void	read_from_file (const std::string &name)
	Load the mesh from a file. More...

void	read_from_file (std::istream &ist)
	Load the mesh from a text stream. More...

void	copy_from (const mesh &m)
	Clone a mesh.

void	Bank_refine (dal::bit_vector)
	Use the Bank strategy to refine some convexes.

Public Member Functions inherited from getfem::context_dependencies
bool	context_check () const
	return true if update_from_context was called

Detailed Description

Describe a mesh (collection of convexes (elements) and points).

Note that mesh object have no copy constructor, use mesh::copy_from instead. This class inherits from bgeot::mesh<base_node> and bgeot::mesh_structure. Compared to bgeot::mesh, It provides some additional methods for convenience (add_simplex_by_points etc...), and it is able to send "messages" to objects that depend on it (for example getfem::mesh_fem) when something in the mesh has been modified. For example, when a convex is removed from the mesh, the mesh_fem that uses this mesh automagically removes any finite element on the convex, and renumbers the dof.

Points and convex numbering:

The numbering of points and convexes is not dynamical, which means that when a point or a convex has been removed from the mesh, there might be holes in the numbering. To loop over the set of valid points in the mesh, one should use

for (dal::bv_visitor ip(mesh.points_index()); !ip.finished(); ++ip) {
...
}

instead of

for (size_type ip = 0; ip < mesh.nb_points(); ++ip) {

}

bgeot::size_type

size_t size_type

used as the common size type in the library

Definition: bgeot_poly.h:49

(same thing for the convexes, always use convex_index()).

Definition at line 95 of file getfem_mesh.h.

Member Function Documentation

◆ search_point()

size_type getfem::mesh::search_point	(	const base_node &	pt,
		const scalar_type	radius = `0`
	)		const

inline

Search a point given its coordinates.

Parameters

pt	the point that is searched.

Returns: the point index if pt was found in (or approximatively in) the mesh nodes, size_type(-1) if not found.

Definition at line 209 of file getfem_mesh.h.

◆ add_convex()

template<class ITER >

size_type getfem::mesh::add_convex	(	bgeot::pgeometric_trans	pgt,
		ITER	ipts
	)

inline

Add a convex to the mesh.

This methods assume that the convex nodes have already been added to the mesh.

Parameters

pgt	the geometric transformation of the convex.
ipts	an iterator to a set of point index.

Returns: the number of the new convex.

Definition at line 226 of file getfem_mesh.h.

◆ normal_of_face_of_convex()

base_small_vector getfem::mesh::normal_of_face_of_convex	(	size_type	ic,
		short_type	f,
		const base_node &	pt
	)		const

Return the normal of the given convex face, evaluated at the point pt.

Parameters

ic	the convex number.
f	the face number.
pt	the point at which the normal is taken, in the reference convex. This point should of course be on the correspounding face of the reference convex, except if the geometric transformation is linear: in that case, the normal constant.

Returns: the face normal.

Definition at line 384 of file getfem_mesh.cc.

◆ local_basis_of_face_of_convex() [1/2]

base_matrix getfem::mesh::local_basis_of_face_of_convex	(	size_type	ic,
		short_type	f,
		const base_node &	pt
	)		const

Return a local basis for the convex face.

Parameters

ic	the convex number.
f	the face number.
pt	the point coordinates.

Returns: a matrix with the normal vector in its first column, and the tangent vectors in the other columns.

Definition at line 421 of file getfem_mesh.cc.

◆ local_basis_of_face_of_convex() [2/2]

base_matrix getfem::mesh::local_basis_of_face_of_convex	(	size_type	ic,
		short_type	f,
		size_type	n
	)		const

Return a local basis for the convex face.

Parameters

ic	the convex number.
f	the face number.
n	local point index in the reference convex, at which the basis will be evaluated – should be faster than the function above since it uses a bgeot::geotrans_precomp .

Returns: a matrix with the normal vector in its first column, and the tangent vectors in the other columns.

Definition at line 430 of file getfem_mesh.cc.

◆ convex_area_estimate()

scalar_type getfem::mesh::convex_area_estimate	(	size_type	ic,
		size_type	degree = `2`
	)		const

Return an estimate of the convex area.

Parameters

ic	the convex number
degree	the degree of the approximation integration method used to compute the area.

Definition at line 442 of file getfem_mesh.cc.

◆ convex_radius_estimate()

scalar_type getfem::mesh::convex_radius_estimate ( size_type ic ) const

virtual

Return an estimate of the convex largest dimension.

See also: getfem::convex_quality_estimate

Reimplemented in getfem::torus_mesh.

Definition at line 461 of file getfem_mesh.cc.

◆ minimal_convex_radius_estimate()

scalar_type getfem::mesh::minimal_convex_radius_estimate ( ) const

Return an estimate of the convex smallest dimension.

See also: getfem::convex_radius_estimate

Definition at line 467 of file getfem_mesh.cc.

◆ maximal_convex_radius_estimate()

scalar_type getfem::mesh::maximal_convex_radius_estimate ( ) const

Return an estimate of the convex largest dimension.

See also: getfem::convex_radius_estimate

Definition at line 476 of file getfem_mesh.cc.

◆ region()

const mesh_region getfem::mesh::region ( size_type id ) const

inline

Return the region of index 'id'.

Regions stored in mesh are updated when the mesh is modified (i.e. when a convex is removed from the mesh, it is also removed from all regions of the mesh.

Definition at line 421 of file getfem_mesh.h.

◆ sup_convex_from_regions()

void getfem::mesh::sup_convex_from_regions ( size_type cv )

Remove all references to a convex from all regions stored in the mesh.

Parameters

cv	the convex number.

Definition at line 42 of file getfem_mesh.cc.

◆ optimize_structure()

void getfem::mesh::optimize_structure ( bool with_renumbering = true )

Pack the mesh : renumber convexes and nodes such that there is no holes in their numbering.

Do NOT do the Cuthill-McKee.

Definition at line 223 of file getfem_mesh.cc.

◆ write_to_file() [1/2]

void getfem::mesh::write_to_file ( const std::string & name ) const

Write the mesh to a file.

The format is getfem-specific.

Parameters

name	the file name.

Definition at line 709 of file getfem_mesh.cc.

◆ write_to_file() [2/2]

void getfem::mesh::write_to_file ( std::ostream & ost ) const

Write the mesh to a text stream.

Parameters

ost	the stream.

Definition at line 685 of file getfem_mesh.cc.

◆ read_from_file() [1/2]

void getfem::mesh::read_from_file ( const std::string & name )

Load the mesh from a file.

Parameters

name	the file name.

See also: getfem::import_mesh.

Definition at line 655 of file getfem_mesh.cc.

◆ read_from_file() [2/2]

void getfem::mesh::read_from_file ( std::istream & ist )

Load the mesh from a text stream.

Parameters

ist	the text stream.

See also: getfem::import_mesh.

Definition at line 511 of file getfem_mesh.cc.

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

src/getfem/getfem_mesh.h
src/getfem_mesh.cc

Public Member Functions

Detailed Description

Member Function Documentation

◆ search_point()

◆ add_convex()

◆ normal_of_face_of_convex()

◆ local_basis_of_face_of_convex() [1/2]

◆ local_basis_of_face_of_convex() [2/2]

◆ convex_area_estimate()

◆ convex_radius_estimate()

◆ minimal_convex_radius_estimate()

◆ maximal_convex_radius_estimate()

◆ region()

◆ sup_convex_from_regions()

◆ optimize_structure()

◆ write_to_file() [1/2]

◆ write_to_file() [2/2]

◆ read_from_file() [1/2]

◆ read_from_file() [2/2]