DCEL mesh class - stores a doubly-connected edge mesh. More...

#include <EBGeometry_DCEL_Mesh.hpp>

Collaboration diagram for EBGeometry::DCEL::MeshT< T, Meta >:

[legend]

Public Types
enum class	SearchAlgorithm { Direct , Direct2 }
	Possible search algorithms for DCEL::MeshT. More...

using	Vec3 = Vec3T< T >
	Alias for vector type.

using	Vertex = VertexT< T, Meta >
	Alias for vertex type.

using	Edge = EdgeT< T, Meta >
	Alias for edge type.

using	Face = FaceT< T, Meta >
	Alias for face type.

using	Mesh = MeshT< T, Meta >
	Alias for mesh type.

using	VertexPtr = std::shared_ptr< Vertex >
	Alias for vertex pointer type.

using	EdgePtr = std::shared_ptr< Edge >
	Alias for edge pointer type.

using	FacePtr = std::shared_ptr< Face >
	Alias for face pointer type.

Public Member Functions
	MeshT () noexcept=default
	Default constructor.

	MeshT (const Mesh &a_otherMesh)=delete
	Disallowed copy construction.

	MeshT (Mesh &&a_otherMesh) noexcept=default
	Move constructor.

	MeshT (std::vector< FacePtr > &a_faces, std::vector< EdgePtr > &a_edges, std::vector< VertexPtr > &a_vertices) noexcept
	Full constructor. This provides the faces, edges, and vertices to the mesh.

	~MeshT () noexcept=default
	Destructor (does nothing)

Mesh &	operator= (const Mesh &a_otherMesh)=delete
	Disallowed copy assignment.

Mesh &	operator= (Mesh &&a_otherMesh) noexcept=default
	Move assignment operator.

std::shared_ptr< Mesh >	deepCopy () const
	Create an independent, fully-decoupled copy of this mesh.

void	sanityCheck (const std::string a_id) const
	Perform a sanity check.

void	setSearchAlgorithm (const SearchAlgorithm a_algorithm) noexcept
	Search algorithm for direct signed distance computations.

void	setInsideOutsideAlgorithm (typename Polygon2D< T >::InsideOutsideAlgorithm a_algorithm) noexcept
	Set the inside/outside algorithm to use when computing the signed distance to polygon faces.

void	reconcile (const DCEL::VertexNormalWeight a_weight=DCEL::VertexNormalWeight::Angle) noexcept
	Reconcile function which computes the internal parameters in vertices, edges, and faces for use with signed distance functionality.

void	flip () noexcept
	Flip the mesh, making all the normals change direction.

std::vector< VertexPtr > &	getVertices () noexcept
	Get modifiable vertices in this mesh.

const std::vector< VertexPtr > &	getVertices () const noexcept
	Get immutable vertices in this mesh.

std::vector< Vec3T< T > >	getAllVertexCoordinates () const noexcept
	Return all vertex coordinates in the mesh.

std::vector< EdgePtr > &	getEdges () noexcept
	Get modifiable half-edges in this mesh.

const std::vector< EdgePtr > &	getEdges () const noexcept
	Get immutable half-edges in this mesh.

std::vector< FacePtr > &	getFaces () noexcept
	Get modifiable faces in this mesh.

const std::vector< FacePtr > &	getFaces () const noexcept
	Get immutable faces in this mesh.

T	signedDistance (const Vec3 &a_x0) const noexcept
	Compute the signed distance from a point to this mesh.

T	signedDistance (const Vec3 &a_x0, SearchAlgorithm a_algorithm) const noexcept
	Compute the signed distance from a point to this mesh.

T	unsignedDistance2 (const Vec3 &a_x0) const noexcept
	Compute the unsigned square distance from a point to this mesh.

Protected Member Functions
void	reconcileFaces () noexcept
	Function which computes internal things for the polygon faces.

void	reconcileEdges () noexcept
	Function which computes internal things for the half-edges.

void	reconcileVertices (const DCEL::VertexNormalWeight a_weight) noexcept
	Function which computes internal things for the vertices.

void	flipFaceNormals () noexcept
	Flip all face normals.

void	flipEdgeNormals () noexcept
	Flip all edge normals.

void	flipVertexNormals () noexcept
	Flip all vertex normals.

T	DirectSignedDistance (const Vec3 &a_point) const noexcept
	Implementation of signed distance function which iterates through all faces.

T	DirectSignedDistance2 (const Vec3 &a_point) const noexcept
	Implementation of squared signed distance function which iterates through all faces.

void	incrementWarning (std::map< std::string, size_t > &a_warnings, const std::string &a_warn) const
	Increment a warning. This is used in sanityCheck() for locating holes or bad inputs in the mesh.

void	printWarnings (const std::map< std::string, size_t > &a_warnings, const std::string &a_id) const
	Print all warnings to std::cerr.

Protected Attributes
SearchAlgorithm	m_algorithm = SearchAlgorithm::Direct2
	Search algorithm. Only used in signed distance functions.

std::vector< VertexPtr >	m_vertices
	Mesh vertices.

std::vector< EdgePtr >	m_edges
	Mesh half-edges.

std::vector< FacePtr >	m_faces
	Mesh faces.

Detailed Description

template<class T, class Meta>
class EBGeometry::DCEL::MeshT< T, Meta >

DCEL mesh class - stores a doubly-connected edge mesh.

Mesh class which stores a full DCEL mesh (with signed distance functions)

Template Parameters

T	Floating-point precision type.
Meta	User-defined metadata type.

This encapsulates a full DCEL mesh, and also includes DIRECT signed distance functions. The mesh consists of a set of vertices, half-edges, and polygon faces who each have references to other vertices, half-edges, and polygon faces. The signed distance functions DIRECT, which means that they go through ALL of the polygon faces and compute the signed distance to them. This is extremely inefficient, which is why this class is almost always embedded into a bounding volume hierarchy.

Note: This class is not for the light of heart – it will almost always be instantiated through a file parser which reads vertices and edges from file and builds the mesh from that. Do not try to build a MeshT object yourself, use file parsers!

Template Parameters

T	Floating-point precision type.
Meta	User-defined metadata type.

Member Enumeration Documentation

◆ SearchAlgorithm

template<class T , class Meta >

enum class EBGeometry::DCEL::MeshT::SearchAlgorithm

strong

Possible search algorithms for DCEL::MeshT.

Enumerator
Direct	Computes the signed distance to every face and returns the one with the smallest magnitude. See DirectSignedDistance().
Direct2	Computes the squared unsigned distance to every face to find the closest one, then returns the signed distance to only that face. Equivalent to Direct but usually faster since it avoids a square root per face. See DirectSignedDistance2().

Constructor & Destructor Documentation

◆ MeshT() [1/4]

template<class T , class Meta >

EBGeometry::DCEL::MeshT< T, Meta >::MeshT ( )

defaultnoexcept

Default constructor.

Leaves the mesh empty (no vertices, edges, or faces) with the default search algorithm; use define() or the mutable getVertices()/getEdges()/getFaces() to populate it.

◆ MeshT() [2/4]

template<class T , class Meta >

EBGeometry::DCEL::MeshT< T, Meta >::MeshT ( const Mesh & a_otherMesh )

delete

Disallowed copy construction.

Copying is deliberately disallowed: a shallow copy of m_vertices/m_edges/m_faces would share the same underlying vertex/edge/face objects as the original (they reference each other internally), so it would not behave like an independent mesh – mutating the "copy" would also mutate the original. Use a file parser to build an independent mesh instead. Moving is allowed (see the move constructor), since that transfers ownership rather than aliasing it.

Parameters

[in] a_otherMesh Other mesh.

◆ MeshT() [3/4]

template<class T , class Meta >

EBGeometry::DCEL::MeshT< T, Meta >::MeshT ( Mesh && a_otherMesh )

defaultnoexcept

Move constructor.

Parameters

[in,out] a_otherMesh Other mesh.

◆ MeshT() [4/4]

template<class T , class Meta >

EBGeometry::DCEL::MeshT< T, Meta >::MeshT	(	std::vector< FacePtr > &	a_faces,
		std::vector< EdgePtr > &	a_edges,
		std::vector< VertexPtr > &	a_vertices
	)

noexcept

Full constructor. This provides the faces, edges, and vertices to the mesh.

Copies the three vectors directly into m_faces/m_edges/m_vertices. This only associates pointer structures through the mesh; internal parameters like face area and normal are computed by reconcile().

Parameters

[in]	a_faces	Polygon faces
[in]	a_edges	Half-edges
[in]	a_vertices	Vertices

Note: The constructor arguments should provide a complete DCEL mesh description. This is usually done through a file parser which reads a mesh file format and creates the DCEL mesh structure

Member Function Documentation

◆ deepCopy()

template<class T , class Meta >

std::shared_ptr< Mesh > EBGeometry::DCEL::MeshT< T, Meta >::deepCopy ( ) const

inline

Create an independent, fully-decoupled copy of this mesh.

Since copy construction/assignment are disallowed (see their documentation), this is the supported way to duplicate a mesh. Unlike a shallow copy, this creates brand new VertexT/EdgeT/FaceT objects and relinks all of their internal pointers (outgoing edge, pair edge, next edge, half edge, adjacent faces) so that the copy shares no vertex, edge, or face with the original – mutating one mesh does not affect the other. Every field is preserved exactly (position, normal vector, centroid, area, meta-data, search algorithm) rather than recomputed, so a mesh that has had flipNormal()/flip() called on it and not yet been re-reconciled will be copied faithfully rather than silently "un-flipped".

Returns: A new mesh, independent of this one.

◆ DirectSignedDistance()

template<class T , class Meta >

T EBGeometry::DCEL::MeshT< T, Meta >::DirectSignedDistance ( const Vec3 & a_point ) const

inlineprotectednoexcept

Implementation of signed distance function which iterates through all faces.

Parameters

[in] a_point 3D point

Returns: Signed distance to the nearest face.

◆ DirectSignedDistance2()

template<class T , class Meta >

T EBGeometry::DCEL::MeshT< T, Meta >::DirectSignedDistance2 ( const Vec3 & a_point ) const

inlineprotectednoexcept

Implementation of squared signed distance function which iterates through all faces.

This first find the face with the smallest unsigned square distance, and the returns the signed distance to that face (more efficient than the other version).

Parameters

[in] a_point 3D point

Returns: Signed distance to the nearest face.

◆ flip()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::flip ( )

inlinenoexcept

Flip the mesh, making all the normals change direction.

Note: Should be called AFTER all normals have been computed.

◆ getAllVertexCoordinates()

template<class T , class Meta >

std::vector< Vec3T< T > > EBGeometry::DCEL::MeshT< T, Meta >::getAllVertexCoordinates ( ) const

inlinenoexcept

Return all vertex coordinates in the mesh.

Returns: Vector of 3D coordinates of all vertices.

◆ getEdges() [1/2]

template<class T , class Meta >

const std::vector< EdgePtr > & EBGeometry::DCEL::MeshT< T, Meta >::getEdges ( ) const

inlinenoexcept

Get immutable half-edges in this mesh.

Returns: Const reference to the vector of half-edges.

◆ getEdges() [2/2]

template<class T , class Meta >

std::vector< EdgePtr > & EBGeometry::DCEL::MeshT< T, Meta >::getEdges ( )

inlinenoexcept

Get modifiable half-edges in this mesh.

Returns: Reference to the vector of half-edges.

◆ getFaces() [1/2]

template<class T , class Meta >

const std::vector< FacePtr > & EBGeometry::DCEL::MeshT< T, Meta >::getFaces ( ) const

inlinenoexcept

Get immutable faces in this mesh.

Returns: Const reference to the vector of polygon faces.

◆ getFaces() [2/2]

template<class T , class Meta >

std::vector< FacePtr > & EBGeometry::DCEL::MeshT< T, Meta >::getFaces ( )

inlinenoexcept

Get modifiable faces in this mesh.

Returns: Reference to the vector of polygon faces.

◆ getVertices() [1/2]

template<class T , class Meta >

const std::vector< VertexPtr > & EBGeometry::DCEL::MeshT< T, Meta >::getVertices ( ) const

inlinenoexcept

Get immutable vertices in this mesh.

Returns: Const reference to the vector of vertices.

◆ getVertices() [2/2]

template<class T , class Meta >

std::vector< VertexPtr > & EBGeometry::DCEL::MeshT< T, Meta >::getVertices ( )

inlinenoexcept

Get modifiable vertices in this mesh.

Returns: Reference to the vector of vertices.

◆ incrementWarning()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::incrementWarning	(	std::map< std::string, size_t > &	a_warnings,
		const std::string &	a_warn
	)		const

inlineprotected

Increment a warning. This is used in sanityCheck() for locating holes or bad inputs in the mesh.

Parameters

[in]	a_warnings	Map of all registered warnings
[in]	a_warn	Current warning to increment by

◆ operator=() [1/2]

template<class T , class Meta >

Mesh & EBGeometry::DCEL::MeshT< T, Meta >::operator= ( const Mesh & a_otherMesh )

delete

Disallowed copy assignment.

Has the same rationale as the disallowed copy constructor; see its documentation.

Parameters

[in] a_otherMesh Other mesh.

Returns: Reference to (*this).

◆ operator=() [2/2]

template<class T , class Meta >

Mesh & EBGeometry::DCEL::MeshT< T, Meta >::operator= ( Mesh && a_otherMesh )

defaultnoexcept

Move assignment operator.

Parameters

[in,out] a_otherMesh Other mesh.

Returns: Reference to (*this).

◆ printWarnings()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::printWarnings	(	const std::map< std::string, size_t > &	a_warnings,
		const std::string &	a_id
	)		const

inlineprotected

Print all warnings to std::cerr.

Parameters

[in]	a_warnings	List of warnings (generated by sanityCheck)
[in]	a_id	Identifier used when printing warnings (can be empty string)

◆ reconcile()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::reconcile ( const DCEL::VertexNormalWeight a_weight = DCEL::VertexNormalWeight::Angle )

inlinenoexcept

Reconcile function which computes the internal parameters in vertices, edges, and faces for use with signed distance functionality.

Parameters

[in] a_weight Vertex angle weighting function. Either VertexNormalWeight::None for unweighted vertex normals or VertexNormalWeight::Angle for the pseudonormal

This will reconcile faces, edges, and vertices, e.g. computing the area and normal vector for faces

◆ reconcileEdges()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::reconcileEdges ( )

inlineprotectednoexcept

Function which computes internal things for the half-edges.

Note: This calls DCEL::EdgeT<T, Meta>::reconcile()

◆ reconcileFaces()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::reconcileFaces ( )

inlineprotectednoexcept

Function which computes internal things for the polygon faces.

Note: This calls DCEL::FaceT<T, Meta>::reconcile()

◆ reconcileVertices()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::reconcileVertices ( const DCEL::VertexNormalWeight a_weight )

inlineprotectednoexcept

Function which computes internal things for the vertices.

Parameters

[in] a_weight Vertex angle weighting

Note: This calls DCEL::VertexT<T, Meta>::computeVertexNormalAverage() or DCEL::VertexT<T, Meta>::computeVertexNormalAngleWeighted()

◆ sanityCheck()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::sanityCheck ( const std::string a_id ) const

inline

Perform a sanity check.

This will provide error messages if vertices are badly linked, faces are nullptr, and so on. These messages are logged by calling incrementWarning() which identifies types of errors that can occur, and how many of those errors have occurred.

Parameters

[in] a_id Identifier when printing error messages (can be empty string).

◆ setInsideOutsideAlgorithm()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::setInsideOutsideAlgorithm ( typename Polygon2D< T >::InsideOutsideAlgorithm a_algorithm )

inlinenoexcept

Set the inside/outside algorithm to use when computing the signed distance to polygon faces.

Computing the signed distance to faces requires testing if a point projected to a polygo face plane falls inside or outside the polygon face. There are multiple algorithms to use here.

Parameters

[in] a_algorithm Algorithm to use

◆ setSearchAlgorithm()

template<class T , class Meta >

void EBGeometry::DCEL::MeshT< T, Meta >::setSearchAlgorithm ( const SearchAlgorithm a_algorithm )

inlinenoexcept

Search algorithm for direct signed distance computations.

Parameters

[in] a_algorithm Algorithm to use

◆ signedDistance() [1/2]

template<class T , class Meta >

T EBGeometry::DCEL::MeshT< T, Meta >::signedDistance ( const Vec3 & a_x0 ) const

inlinenoexcept

Compute the signed distance from a point to this mesh.

Parameters

[in] a_x0 3D point in space.

This function will iterate through ALL faces in the mesh and return the value with the smallest magnitude. This is horrendously slow, which is why this function is almost never called. Rather, MeshT<T, Meta> can be embedded in a bounding volume hierarchy for faster access.

Note: This will call the other version with the object's search algorithm.

Returns: Signed distance to the mesh; negative inside, positive outside. Returns +infinity if the mesh has no faces.

◆ signedDistance() [2/2]

template<class T , class Meta >

T EBGeometry::DCEL::MeshT< T, Meta >::signedDistance	(	const Vec3 &	a_x0,
		SearchAlgorithm	a_algorithm
	)		const

inlinenoexcept

Compute the signed distance from a point to this mesh.

Parameters

[in]	a_x0	3D point in space.
[in]	a_algorithm	Search algorithm

This function will iterate through ALL faces in the mesh and return the value with the smallest magnitude. This is horrendously slow, which is why this function is almost never called. Rather, MeshT<T, Meta> can be embedded in a bounding volume hierarchy for faster access.

Returns: Signed distance to the mesh; negative inside, positive outside. Returns +infinity if the mesh has no faces.

◆ unsignedDistance2()

template<class T , class Meta >

T EBGeometry::DCEL::MeshT< T, Meta >::unsignedDistance2 ( const Vec3 & a_x0 ) const

inlinenoexcept

Compute the unsigned square distance from a point to this mesh.

Parameters

[in] a_x0 3D point in space.

This function will iterate through ALL faces in the mesh and return the value with the smallest magnitude. This is horrendously slow, which is why this function is almost never called. Rather, MeshT<T, Meta> can be embedded in a bounding volume hierarchy for faster access.

Returns: Squared unsigned distance to the nearest face, or +infinity if the mesh has no faces.

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

Source/EBGeometry_DCEL.hpp
Source/EBGeometry_DCEL_Mesh.hpp

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ SearchAlgorithm

Constructor & Destructor Documentation

◆ MeshT() [1/4]

◆ MeshT() [2/4]

◆ MeshT() [3/4]

◆ MeshT() [4/4]

Member Function Documentation

◆ deepCopy()

◆ DirectSignedDistance()

◆ DirectSignedDistance2()

◆ flip()

◆ getAllVertexCoordinates()

◆ getEdges() [1/2]

◆ getEdges() [2/2]

◆ getFaces() [1/2]

◆ getFaces() [2/2]

◆ getVertices() [1/2]

◆ getVertices() [2/2]

◆ incrementWarning()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ printWarnings()

◆ reconcile()

◆ reconcileEdges()

◆ reconcileFaces()

◆ reconcileVertices()

◆ sanityCheck()

◆ setInsideOutsideAlgorithm()

◆ setSearchAlgorithm()

◆ signedDistance() [1/2]

◆ signedDistance() [2/2]

◆ unsignedDistance2()