CGAL 5.3 - 3D Mesh Generation
MeshDomain_3 Concept Reference

Inherited by CGAL::Mesh_domain_with_polyline_features_3< MeshDomain_3 >.

Definition

The concept MeshDomain_3 describes the knowledge required on the object to be discretized. The concept MeshDomain_3 is the concept to be used when the input domain does not have \( 0\) or \( 1\)-dimensional features that need to be accurately approximated by the mesh. In such a case, the queries issued by the meshing process concern only the faces of the input domain with dimension \( 3\) and \( 2\), that are respectively called subdomains and surface patches.

More specifically the concept MeshDomain_3 provides a method to localize a point with respect to the input domain and its subdomains. Moreover, as the concept SurfaceMeshTraits_3, it also provides predicates to test whether a query segment (or a ray, or a line) intersects the boundary of the domain or of the subdomains, and constructors to compute some intersection point if any. It also includes a method able to provide a small set of initial points on the boundary.

In the following we consider only proper intersection with the domain and subdomain boundaries. A segment, ray or line is said to intersect properly the domain boundary (resp. a subdomain boundary) if it includes points which are strictly inside and strictly outside the domain (resp. the subdomain).

Has Models:

CGAL::Polyhedral_mesh_domain_3<Polyhedron,IGT,TriangleAccessor>

CGAL::Labeled_mesh_domain_3<BGT>

See also
MeshVertexBase_3
MeshCellBase_3
CGAL::make_mesh_3()
CGAL::refine_mesh_3()

Types

typedef unspecified_type R
 Geometric traits class. More...
 
typedef unspecified_type Point_3
 Point type.
 
typedef unspecified_type Segment_3
 Segment type.
 
typedef unspecified_type Ray_3
 Ray type.
 
typedef unspecified_type Line_3
 Line type.
 
typedef CGAL::Tag_false Has_features
 A type to distinguish MeshDomain_3 models from MeshDomainWithFeatures_3 models.
 
typedef unspecified_type Subdomain_index
 Type of indices for subdomains of the input domain. More...
 
typedef unspecified_type Surface_patch_index
 Type of indices for surface patches (boundaries and interfaces) of the input domain. More...
 
typedef unspecified_type Index
 Type of indices to be stored at mesh vertices to characterize the lowest dimensional face of the input complex on which the vertex lies. More...
 
typedef std::tuple< Point_3, Index, int > Intersection
 Returns type of Construct_intersection queries. More...
 
typedef unspecified_type Construct_initial_points
 A function object to construct a set of initial points on the surface of the domain. More...
 
typedef unspecified_type Is_in_domain
 A function object to query whether a point is in the input domain or not. More...
 
typedef unspecified_type Do_intersect_surface
 A function object which answers intersection queries between the surface patches of the domain and objects of type Segment_3, Ray_3 or Line_3. More...
 
typedef unspecified_type Construct_intersection
 A function object to construct the intersection between an object of type Segment_3, Ray_3 or Line_3 and an interface. More...
 

Bounding box

Since CGAL-4.8, a model of MeshDomain_3 must provide a function providing a bounding box of the domain.

Bbox_3 bbox () const
 Returns a bounding box of the domain.
 

Operations

The following functions give access to the function objects:

Construct_initial_points construct_initial_points_object ()
 
Is_in_domain is_in_domain_object ()
 
Do_intersect_surface do_intersect_surface_object ()
 
Construct_intersection construct_intersection_object ()
 

Index Conversion

These methods are designed to convert indices:

Index index_from_surface_patch_index (Surface_patch_index surface_patch_index)
 Returns the index to be stored at a vertex lying on the surface patch identified by surface_patch_index.
 
Index index_from_subdomain_index (Subdomain_index subdomain_index)
 Returns the index to be stored at a vertex lying in the subdomain identified by subdomain_index.
 
Surface_patch_index surface_patch_index (Index index)
 Returns the Surface_patch_index of the surface patch where lies a vertex with dimension 2 and index index.
 
Subdomain_index subdomain_index (Index index)
 Returns the index of the subdomain containing a vertex with dimension 3 and index index.
 

Member Typedef Documentation

◆ Construct_initial_points

A function object to construct a set of initial points on the surface of the domain.

Provides the following operators:

template<typename OutputIterator>
OutputIterator operator()(OutputIterator pts)

template<typename OutputIterator>
OutputIterator operator()(int n, OutputIterator pts)

Those two operators output a set of (n) surface points to the output iterator pts, as objects of type std::pair<Point_3, Index>. If n is not given, the functor must provide enough points to initialize the mesh generation process.

◆ Construct_intersection

A function object to construct the intersection between an object of type Segment_3, Ray_3 or Line_3 and an interface.

Provides the operators:

Intersection operator()(Segment_3 s)

Intersection operator()(Ray_3 r)

Intersection operator()(Line_3 l)

Precondition
do_intersect_surface(s/r/l) == true

◆ Do_intersect_surface

A function object which answers intersection queries between the surface patches of the domain and objects of type Segment_3, Ray_3 or Line_3.

Provides the operators:

boost::optional<Surface_patch_index> operator()(Segment_3 s)

boost::optional<Surface_patch_index> operator()(Ray_3 r)

boost::optional<Surface_patch_index> operator()(Line_3 l)

The return type of the operators tell whether or not the query intersects a surface patch. In the positive case, it provides (through operator*()) the Surface_patch_index of one of the intersected surface patches.

◆ Index

Type of indices to be stored at mesh vertices to characterize the lowest dimensional face of the input complex on which the vertex lies.

Must be a model of CopyConstructible, Assignable, DefaultConstructible and EqualityComparable.

◆ Intersection

typedef std::tuple<Point_3, Index, int> MeshDomain_3::Intersection

Returns type of Construct_intersection queries.

int represents the dimension of the lower dimensional face of the input complex on which the intersection point lies and Index is the index of this face.

◆ Is_in_domain

A function object to query whether a point is in the input domain or not.

In the positive case, it outputs the subdomain which includes the query point. Provides the operator:

boost::optional<Subdomain_index> operator()(Point_3 p)

◆ R

Geometric traits class.

This type is defined to ensure compatibility with CGAL::Kernel_traits<T>.

◆ Subdomain_index

Type of indices for subdomains of the input domain.

Must be a model of CopyConstructible, Assignable, DefaultConstructible and EqualityComparable. The default constructed value must match the label of the exterior of the domain (which contains at least the unbounded component).

◆ Surface_patch_index

Type of indices for surface patches (boundaries and interfaces) of the input domain.

Must be a model of CopyConstructible, Assignable, DefaultConstructible and EqualityComparable. The default constructed value must be the index value assigned to a non surface facet.