ShellElement Class Reference

The shell element class defines triangular and quadrilateral polygonal elements. More...

#include <Mesh/DataStructures/shellelement.h>

Inheritance diagram for ShellElement:

Public Member Functions
	ShellElement (long ID, long compID, Node &n0, Node &n1, Node &n2, bool allowBadNormal=false, unsigned stateSize=0, unsigned integerDataSize=0)
	ShellElement (long ID, long compID, Node &n0, Node &n1, Node &n2, Node &n3, bool allowBadNormal=false, unsigned stateSize=0, unsigned integerDataSize=0)
	~ShellElement () override
void	addToNormal (const Vector3d &v)
double	area () const
void	attachElement () override
void	attachNodes () override
bool	calcNormal (bool allowWarnings=true, bool updateOldNormal=true)
void	convertToQuad (Node &oppositeNode, int afterIndex)
void	copyNormal (ShellElement &elem)
void	detachElement () override
const Vector3d &	getNormal () const
const Vector3d &	getOldNormal () const
bool	isDuplicateOf (const ShellElement &elem) const
bool	isQuad () const
bool	isSplinter (double edgeDistTol_2) const
bool	isTri () const
double	minNodeToEdgeDist () const
double	minNodeToEdgeDist (Node *&closeNode) const
double	minNodeToEdgeDist2 () const
double	minNodeToEdgeDist2 (Node *&closeNode) const
Node &	nearestNode (Node &node) const
void	scaleNormal (double d)
void	scaleOldNormal (double d)
void	scaleToUnitNormal ()
void	setNormal (const Vector3d &v)
void	setOldNormal (const Vector3d &v)
ShellElement *	sharedEdge (int indexToNode) const
ShellElement *	sharedEdge (Node &node_A, Node &node_B) const
void	truncateToTRI3 (ElementNodes::iterator j)
void	truncateToTRI3 (Node &node)
void	updateOldNormal ()
Deprecated functions
bool	CalcNormal (bool allowWarnings=true, bool updateOldNormal=true)
void	CopyNormal (ShellElement &elem)
void	UpdateOldNormal ()
ShellElementTypes	GetElementType () const
bool	IsDuplicateOf (const ShellElement &elem) const
void	TruncateToTRI3 (ElementNodes::iterator j)
void	TruncateToTRI3 (Node &node)
void	ConvertToQuad (Node &oppositeNode, int afterIndex)
bool	IsTri () const
bool	IsQuad () const
bool	IsSplinter (double edgeDistTol_2) const
bool	IsPorousInterface () const
bool	IsInflow () const
bool	IsBoundary () const
bool	InvolvedInCollision () const
void	SetCollided ()
double	MinNodeToEdgeDist2 (Node *&closeNode) const
double	MinNodeToEdgeDist2 () const
double	MinNodeToEdgeDist (Node *&closeNode) const
double	MinNodeToEdgeDist () const
Node &	NearestNode (Node &node) const
double	Area () const
ShellElement *	SharedEdge (Node &node_A, Node &node_B) const
ShellElement *	SharedEdge (int indexToNode) const
const Vector3d &	GetNormal () const
const Vector3d &	GetOldNormal () const
void	SetOldNormal (const Vector3d &v)
void	ScaleOldNormal (double d)
void	SetNormal (const Vector3d &v)
void	ScaleNormal (double d)
void	AddToNormal (const Vector3d &v)
void	ScaleToUnitNormal ()
Public Member Functions inherited from Element
virtual	~Element ()=default
virtual void	attachElement ()=0
virtual void	attachNodes ()=0
virtual void	detachElement ()=0
Vector3d	getCentroid () const
Node &	getNode (int index) const
ElementNodes &	getNodes ()
const ElementNodes &	getNodes () const
Node *	nodeAfter (const Node &node) const
Node *	nodeBefore (const Node &node) const
unsigned	numNodes () const
void	setNode (int index, Node &n)
void	setNodeStates (int index, const Vector3d &v)
void	setNodeStates (int index, double v)
void	setNodeStates (int index, int v)
bool	usesNode (const Node &node) const
bool	UsesNode (const Node &node) const
bool	usesNode (long id) const
bool	UsesNode (long id) const
const ElementNodes &	GetNodes () const
ElementNodes &	GetNodes ()
Node &	GetNode (int index) const
void	SetNode (int index, Node &n)
Node *	NodeBefore (const Node &node) const
Node *	NodeAfter (const Node &node) const
void	setNodeFlags (unsigned flag, bool b=true)
void	SetNodeFlags (unsigned flag, bool b=true)
void	SetNodeStates (int index, double v)
void	SetNodeStates (int index, const Vector3d &v)
Vector3d	GetCentroid () const
Public Member Functions inherited from Entity
long	getCompID () const
	Get the ID of the component this entity belongs to.
void	setCompID (long compID)
void	SetCompID (long compID)
long	GetCompID () const
Public Member Functions inherited from NumberedObject
	NumberedObject (long ID)
	Create an object with the specified ID and all flags except isValid not set.
void	clearFlag (unsigned flag)
	Clear flag. Do not use this to manipulate the isValid flag, since list managers are responsible for that.
void	copyFlags (const NumberedObject &t)
long	getID () const
long	getIndex () const
bool	isFlagSet (unsigned flag) const
bool	isValid () const
void	setFlag (unsigned flag, bool b=true)
	Set flag to b. Do not use this to manipulate the isValid flag, since list managers are responsible for that.
void	setID (long ID)
void	setIndex (long i)
void	SetID (long ID)
long	GetID () const
void	SetIndex (long i)
long	GetIndex () const
bool	IsFlagSet (unsigned flag) const
void	ClearFlag (unsigned flag)
void	SetFlag (unsigned flag)
void	setFlagTo (unsigned flag, bool b=true)
void	SetFlagTo (unsigned flag, bool b=true)
bool	IsValid () const
Public Member Functions inherited from State
	State (unsigned stateSize, unsigned integerDataSize)
	~State ()
void	addToIntegerData (int index, long val)
void	addToState (int index, const Vector3d &v)
void	addToState (int index, double val)
void	copyIntegerData (int index, const State &s)
void	copyState (int index, const State &s)
void	copyStateVector (int index, const State &s)
long	getIntegerData (int index) const
double	getState (int index) const
Vector3d	getStateVector (int index) const
void	setIntegerData (int index, long val)
void	setState (int index, const Vector3d &v)
void	setState (int index, double val)
void	CopyIntegerData (int index, const State &s)
void	AddToIntegerData (int index, long val)
void	SetIntegerData (int index, long val)
long	GetIntegerData (int index) const
void	CopyStateVector (int index, const State &s)
void	CopyState (int index, const State &s)
void	AddToState (int index, const Vector3d &v)
void	AddToState (int index, double val)
double	GetState (int index) const
Vector3d	GetStateVector (int index) const
void	SetState (int index, double val)
void	SetState (int index, const Vector3d &v)

Static Public Member Functions
static void	copyElementStates (const StateInfoArray &states, const ShellElement &source, ShellElement &dest)

Additional Inherited Members
Public Types inherited from Element
typedef std::vector< Node * >	ElementNodes
Public Types inherited from NumberedObject
enum	{   flag0 , flag1 , flag2 , flag3 ,   flag4 , flag5 , flag6 , flag7 ,   flag8 , flag9 , flag10 , flag11 ,   flag12 , flag13 , flag14 , flag15 }
Protected Member Functions inherited from Element
	Element (long IDnum, long compIDnum, unsigned stateSize=0, unsigned integerDataSize=0)
Protected Member Functions inherited from Entity
	Entity (long id, long compID)
Protected Attributes inherited from Element
ElementNodes	nodes_
Related Functions inherited from NumberedObject
int	bitMask (unsigned pos)

Detailed Description

There are some assumptions made in various algorithms about some of the data stored for a shell element. In general, you should not try to modify a shell element directly, but most non-modifying member functions that return information about the element should be safe to call. Note that a shell element should only be created and removed by a ShellElementList and never directly by the user.

The node ordering of a shell element is such that the normal vector follows the right-hand rule.

Constructor & Destructor Documentation

ShellElement() [1/2]

ShellElement	(	long	ID,
		long	compID,
		Node &	n0,
		Node &	n1,
		Node &	n2,
		bool	allowBadNormal = false,
		unsigned	stateSize = 0,
		unsigned	integerDataSize = 0
	)

Creates a tri shell element and calculates its normal by calling CalcNormal() just before returning. It does not try to attach the element to anything. In particular, it does not update the attached element lists for the nodes it uses. This is the responsibility of the caller.

ShellElement() [2/2]

ShellElement	(	long	ID,
		long	compID,
		Node &	n0,
		Node &	n1,
		Node &	n2,
		Node &	n3,
		bool	allowBadNormal = false,
		unsigned	stateSize = 0,
		unsigned	integerDataSize = 0
	)

Creates a quad shell element and calculates its normal by calling CalcNormal() just before returning. It does not try to attach the element to anything. In particular, it does not update the attached element lists for the nodes it uses. This is the responsibility of the caller.

~ShellElement()

~ShellElement ( )

override

Member Function Documentation

addToNormal()

void addToNormal ( const Vector3d &  v )

inline

AddToNormal()

void AddToNormal ( const Vector3d &  v )

inline

area()

double area

(

)

const

Returns

The area of the element.

Area()

double Area ( ) const

inline

attachElement()

void attachElement ( )

overridevirtual

Implements Element.

attachNodes()

void attachNodes ( )

overridevirtual

The shell element's nodes are attached to each other only around the edges. Diagonally opposing nodes are not attached to each other.

Implements Element.

calcNormal()

bool calcNormal	(	bool	allowWarnings = true,
		bool	updateOldNormal = true
	)

Parameters

allowWarnings	If this is true, then any problems found will be reported. If it is false, then if a problem is encountered, the old normal is retained where an invalid normal has been created, and the function then returns.
updateOldNormal	The shell element also retains a copy of a previous normal vector (this is useful for some algorithms). If this parameter is true, the old normal vector is set to the element's normal vector at the time this function was called, regardless of whether or not the calculation of the new normal vector is successful.

For triangular elements, the normal is calculated from the cross-product of the three nodes. For quad elements, the normal is an area-weighted average of the four cross-products (i.e. remove a node and generate the cross-product for the remaining three). This is necessary because quad elements can be warped, so we cannot just take any three nodes to find the element normal. The area-weighting is a natural part of using the cross-product and sensibly weights each of the normals.

A check is made to see if the normal appears to have flipped its direction. Some algorithms rely on this to detect severe local distortions in the mesh between iterations.

The normal vector is always of unit length.

Returns

True if a warning was found or if a fatal error was found but was explicitly allowed.

CalcNormal()

bool CalcNormal ( bool  allowWarnings = true, bool  updateOldNormal = true  )

inline

convertToQuad()

void convertToQuad	(	Node &	oppositeNode,
		int	afterIndex
	)

ConvertToQuad()

void ConvertToQuad ( Node &  oppositeNode, int  afterIndex  )

inline

copyElementStates()

void copyElementStates ( const StateInfoArray &  states, const ShellElement &  source, ShellElement &  dest  )

static

copyNormal()

void copyNormal

(

ShellElement &

elem

)

CopyNormal()

void CopyNormal ( ShellElement &  elem )

inline

detachElement()

void detachElement ( )

overridevirtual

Detach this element from its nodes' attached elements list, then rebuild the attached nodes list for each element node too.

Note

Unlike the detachElement() function for Segment and VolumeElement, the ShellElement class forcibly rebuilds the attached node lists at the end of this call. This behavior will eventually be changed to make it consistent with those classes, but currently the PreProcess module depends on this behavior.

Implements Element.

GetElementType()

ShellElementTypes GetElementType ( ) const

inline

getNormal()

const Vector3d & getNormal ( ) const

inline

Returns

The normal vector for the shell element. This vector can get out of date, such as when the element's nodes are moved but the normal hasn't yet been updated. If you want to be sure the normal vector is current, call CalcNormal first.

GetNormal()

const Vector3d & GetNormal ( ) const

inline

getOldNormal()

const Vector3d & getOldNormal ( ) const

inline

GetOldNormal()

const Vector3d & GetOldNormal ( ) const

inline

InvolvedInCollision()

bool InvolvedInCollision ( ) const

inline

IsBoundary()

bool IsBoundary ( ) const

inline

isDuplicateOf()

bool isDuplicateOf

(

const ShellElement &

elem

)

const

Returns

True if elem is a duplicate of this element, ignoring the direction of the normal vector.

IsDuplicateOf()

bool IsDuplicateOf ( const ShellElement &  elem ) const

inline

IsInflow()

bool IsInflow ( ) const

inline

IsPorousInterface()

bool IsPorousInterface ( ) const

inline

isQuad()

bool isQuad ( ) const

inline

Returns

True if this element is a quad.

IsQuad()

bool IsQuad ( ) const

inline

isSplinter()

bool isSplinter ( double  edgeDistTol_2 ) const

inline

IsSplinter()

bool IsSplinter ( double  edgeDistTol_2 ) const

inline

isTri()

bool isTri ( ) const

inline

Returns

True if this element is a tri.

IsTri()

bool IsTri ( ) const

inline

minNodeToEdgeDist() [1/2]

double minNodeToEdgeDist ( ) const

inline

MinNodeToEdgeDist() [1/2]

double MinNodeToEdgeDist ( ) const

inline

minNodeToEdgeDist() [2/2]

double minNodeToEdgeDist ( Node *&  closeNode ) const

inline

MinNodeToEdgeDist() [2/2]

double MinNodeToEdgeDist ( Node *&  closeNode ) const

inline

minNodeToEdgeDist2() [1/2]

double minNodeToEdgeDist2

(

)

const

MinNodeToEdgeDist2() [1/2]

double MinNodeToEdgeDist2 ( ) const

inline

minNodeToEdgeDist2() [2/2]

double minNodeToEdgeDist2

(

Node *&

closeNode

)

const

MinNodeToEdgeDist2() [2/2]

double MinNodeToEdgeDist2 ( Node *&  closeNode ) const

inline

nearestNode()

Node & nearestNode

(

Node &

node

)

const

NearestNode()

Node & NearestNode ( Node &  node ) const

inline

scaleNormal()

void scaleNormal ( double  d )

inline

ScaleNormal()

void ScaleNormal ( double  d )

inline

scaleOldNormal()

void scaleOldNormal ( double  d )

inline

ScaleOldNormal()

void ScaleOldNormal ( double  d )

inline

scaleToUnitNormal()

void scaleToUnitNormal ( )

inline

Make sure this element's normal is a unit vector. If the normal was a zero vector, an exception of type ScaledZeroVectorError is thrown.

ScaleToUnitNormal()

void ScaleToUnitNormal ( )

inline

SetCollided()

void SetCollided ( )

inline

setNormal()

void setNormal ( const Vector3d &  v )

inline

Set the normal vector of this element to v. No attempt is made to check if this makes sense for the element.

SetNormal()

void SetNormal ( const Vector3d &  v )

inline

setOldNormal()

void setOldNormal ( const Vector3d &  v )

inline

SetOldNormal()

void SetOldNormal ( const Vector3d &  v )

inline

sharedEdge() [1/2]

ShellElement * sharedEdge

(

int

indexToNode

)

const

Returns

The first element found to share this element's edge as defined by the start of the edge at nodes[indexToNode ]. If no element shares the edge, it returns NULL.

SharedEdge() [1/2]

ShellElement * SharedEdge ( int  indexToNode ) const

inline

sharedEdge() [2/2]

ShellElement * sharedEdge	(	Node &	node_A,
		Node &	node_B
	)		const

Returns

The first element found to share this element's edge as defined by the two nodes node_A and node_B. If no element shares the edge, it returns NULL. The relative ordering of node_A and node_B is not important.

SharedEdge() [2/2]

ShellElement * SharedEdge ( Node &  node_A, Node &  node_B  ) const

inline

truncateToTRI3() [1/2]

void truncateToTRI3

(

ElementNodes::iterator

j

)

TruncateToTRI3() [1/2]

void TruncateToTRI3 ( ElementNodes::iterator  j )

inline

truncateToTRI3() [2/2]

void truncateToTRI3 ( Node &  node )

inline

TruncateToTRI3() [2/2]

void TruncateToTRI3 ( Node &  node )

inline

updateOldNormal()

void updateOldNormal ( )

inline

UpdateOldNormal()

void UpdateOldNormal ( )

inline