helper class to perform cell tessellation More...

#include <vtkSimpleCellTessellator.h>

Inheritance diagram for vtkSimpleCellTessellator:

Collaboration diagram for vtkSimpleCellTessellator:

Public Types
typedef vtkGenericCellTessellator	Superclass

Public Types inherited from vtkGenericCellTessellator
typedef vtkObject	Superclass

Public Types inherited from vtkObject
typedef vtkObjectBase	Superclass

Public Member Functions
virtual int	IsA (const char *type)

vtkSimpleCellTessellator *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent)

void	Reset ()

void	Initialize (vtkGenericDataSet *ds)

int	GetFixedSubdivisions ()

int	GetMaxSubdivisionLevel ()

int	GetMaxAdaptiveSubdivisions ()

void	SetFixedSubdivisions (int level)

void	SetMaxSubdivisionLevel (int level)


virtual vtkGenericAdaptorCell *	GetGenericCell ()


void	TessellateFace (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkIdType index, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)


void	Tessellate (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)


void	Triangulate (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)


void	SetSubdivisionLevels (int fixed, int maxLevel)

Public Member Functions inherited from vtkGenericCellTessellator
vtkGenericCellTessellator *	NewInstance () const

void	InitErrorMetrics (vtkGenericDataSet *ds)

void	GetMaxErrors (double *errors)

virtual void	SetErrorMetrics (vtkCollection *someErrorMetrics)

virtual vtkCollection *	GetErrorMetrics ()

virtual int	GetMeasurement ()

virtual void	SetMeasurement (int)

Public Member Functions inherited from vtkObject
vtkObject *	NewInstance () const

virtual void	DebugOn ()

virtual void	DebugOff ()

bool	GetDebug ()

void	SetDebug (bool debugFlag)

virtual void	Modified ()

virtual unsigned long	GetMTime ()

unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)

unsigned long	AddObserver (const char event, vtkCommand , float priority=0.0f)

vtkCommand *	GetCommand (unsigned long tag)

void	RemoveObserver (vtkCommand *)

void	RemoveObservers (unsigned long event, vtkCommand *)

void	RemoveObservers (const char event, vtkCommand )

int	HasObserver (unsigned long event, vtkCommand *)

int	HasObserver (const char event, vtkCommand )

void	RemoveObserver (unsigned long tag)

void	RemoveObservers (unsigned long event)

void	RemoveObservers (const char *event)

void	RemoveAllObservers ()

int	HasObserver (unsigned long event)

int	HasObserver (const char *event)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)

int	InvokeEvent (unsigned long event, void *callData)

int	InvokeEvent (const char event, void callData)

int	InvokeEvent (unsigned long event)

int	InvokeEvent (const char *event)

Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const

virtual void	Delete ()

virtual void	FastDelete ()

void	Print (ostream &os)

virtual void	Register (vtkObjectBase *o)

virtual void	UnRegister (vtkObjectBase *o)

void	SetReferenceCount (int)

void	PrintRevisions (ostream &)

virtual void	PrintHeader (ostream &os, vtkIndent indent)

virtual void	PrintTrailer (ostream &os, vtkIndent indent)

int	GetReferenceCount ()

Static Public Member Functions
static vtkSimpleCellTessellator *	New ()

static int	IsTypeOf (const char *type)

static vtkSimpleCellTessellator *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkGenericCellTessellator
static int	IsTypeOf (const char *type)

static vtkGenericCellTessellator *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkObject
static int	IsTypeOf (const char *type)

static vtkObject *	SafeDownCast (vtkObjectBase *o)

static vtkObject *	New ()

static void	BreakOnError ()

static void	SetGlobalWarningDisplay (int val)

static void	GlobalWarningDisplayOn ()

static void	GlobalWarningDisplayOff ()

static int	GetGlobalWarningDisplay ()

Static Public Member Functions inherited from vtkObjectBase
static int	IsTypeOf (const char *name)

static vtkObjectBase *	New ()

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkSimpleCellTessellator ()

	~vtkSimpleCellTessellator ()

void	CopyPoint (vtkIdType pointId)

void	InsertEdgesIntoEdgeTable (vtkTriangleTile &tri)

void	RemoveEdgesFromEdgeTable (vtkTriangleTile &tri)

void	InsertPointsIntoEdgeTable (vtkTriangleTile &tri)

void	InsertEdgesIntoEdgeTable (vtkTetraTile &tetra)

void	RemoveEdgesFromEdgeTable (vtkTetraTile &tetra)

void	AllocateScalars (int size)

int	FindEdgeReferenceCount (double p1[3], double p2[3], vtkIdType &e1, vtkIdType &e2)

int	GetNumberOfCellsUsingFace (int faceId)

int	GetNumberOfCellsUsingEdge (int edgeId)

int	IsEdgeOnFace (double p1[3], double p2[3])

int	FindEdgeParent2D (double p1[3], double p2[3], int &localId)

int	FindEdgeParent (double p1[3], double p2[3], int &localId)

void	AllocatePointIds (int size)


void	InitTetraTile (vtkTetraTile &root, vtkIdType localIds, vtkIdType ids, int edgeIds, int faceIds)


void	TriangulateTriangle (vtkGenericAdaptorCell cell, vtkIdType localIds, vtkIdType ids, int edgeIds, vtkGenericAttributeCollection att, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData internalPd)


int	FacesAreEqual (int *originalFace, int face[3])

Protected Member Functions inherited from vtkGenericCellTessellator
	vtkGenericCellTessellator ()

	~vtkGenericCellTessellator ()

void	ResetMaxErrors ()

void	SetGenericCell (vtkGenericAdaptorCell *cell)

int	RequiresEdgeSubdivision (double left, double mid, double *right, double alpha)

virtual void	UpdateMaxError (double leftPoint, double midPoint, double *rightPoint, double alpha)

Protected Member Functions inherited from vtkObject
	vtkObject ()

virtual	~vtkObject ()

virtual void	RegisterInternal (vtkObjectBase *, int check)

virtual void	UnRegisterInternal (vtkObjectBase *, int check)

void	InternalGrabFocus (vtkCommand mouseEvents, vtkCommand keypressEvents=NULL)

void	InternalReleaseFocus ()

Protected Member Functions inherited from vtkObjectBase
	vtkObjectBase ()

virtual	~vtkObjectBase ()

virtual void	CollectRevisions (ostream &)

virtual void	ReportReferences (vtkGarbageCollector *)

	vtkObjectBase (const vtkObjectBase &)

void	operator= (const vtkObjectBase &)

Protected Attributes
vtkGenericEdgeTable *	EdgeTable

vtkGenericAdaptorCell *	GenericCell

double *	Scalars

int	ScalarsCapacity

int	PointOffset

vtkGenericCellIterator *	CellIterator

vtkGenericAttributeCollection *	AttributeCollection

vtkGenericDataSet *	DataSet

vtkIdType	NumberOfPoints

int	FixedSubdivisions

int	MaxSubdivisionLevel

int	CurrentSubdivisionLevel

int *	EdgeIds

int *	FaceIds

vtkOrderedTriangulator *	Triangulator

vtkCellArray *	Connectivity

vtkPolygon *	Polygon

vtkIdList *	TriangleIds

vtkIdType *	PointIds

int	PointIdsCapacity


vtkDoubleArray *	TessellatePoints

vtkCellArray *	TessellateCellArray

vtkPointData *	TessellatePointData

Protected Attributes inherited from vtkGenericCellTessellator
vtkCollection *	ErrorMetrics

vtkGenericDataSet *	DataSet

int	Measurement

double *	MaxErrors

int	MaxErrorsCapacity

Protected Attributes inherited from vtkObject
bool	Debug

vtkTimeStamp	MTime

vtkSubjectHelper *	SubjectHelper

Protected Attributes inherited from vtkObjectBase
vtkAtomicInt32	ReferenceCount

vtkWeakPointerBase **	WeakPointers

Friends
class	vtkTetraTile

class	vtkTriangleTile

Detailed Description

helper class to perform cell tessellation

vtkSimpleCellTessellator is a helper class to perform adaptive tessellation of particular cell topologies. The major purpose for this class is to transform higher-order cell types (e.g., higher-order finite elements) into linear cells that can then be easily visualized by VTK. This class works in conjunction with the vtkGenericDataSet and vtkGenericAdaptorCell classes.

This algorithm is based on edge subdivision. An error metric along each edge is evaluated, and if the error is greater than some tolerance, the edge is subdivided (as well as all connected 2D and 3D cells). The process repeats until the error metric is satisfied. Since the algorithm is based on edge subdivision it inherently avoid T-junctions.

A significant issue addressed by this algorithm is to insure face compatibility across neigboring cells. That is, diagonals due to face triangulation must match to insure that the mesh is compatible. The algorithm employs a precomputed table to accelerate the tessellation process. The table was generated with the help of vtkOrderedTriangulator the basic idea is that the choice of diagonal is made only by considering the relative value of the point ids.

See also: vtkGenericCellTessellator vtkGenericSubdivisionErrorMetric vtkAttributesErrorMetric vtkGeometricErrorMetric vtkViewDependentErrorMetric

Tests:: vtkSimpleCellTessellator (Tests)

Definition at line 70 of file vtkSimpleCellTessellator.h.

Member Typedef Documentation

typedef vtkGenericCellTessellator vtkSimpleCellTessellator::Superclass

Definition at line 74 of file vtkSimpleCellTessellator.h.

Constructor & Destructor Documentation

vtkSimpleCellTessellator::vtkSimpleCellTessellator ( )

protected

vtkSimpleCellTessellator::~vtkSimpleCellTessellator ( )

protected

Member Function Documentation

static vtkSimpleCellTessellator* vtkSimpleCellTessellator::New ( )

static

static int vtkSimpleCellTessellator::IsTypeOf ( const char * type )

static

virtual int vtkSimpleCellTessellator::IsA ( const char * name )

virtual

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkGenericCellTessellator.

static vtkSimpleCellTessellator* vtkSimpleCellTessellator::SafeDownCast ( vtkObjectBase * o )

static

virtual vtkObjectBase* vtkSimpleCellTessellator::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkGenericCellTessellator.

vtkSimpleCellTessellator* vtkSimpleCellTessellator::NewInstance ( ) const

void vtkSimpleCellTessellator::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)

virtual

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkGenericCellTessellator.

virtual vtkGenericAdaptorCell* vtkSimpleCellTessellator::GetGenericCell ( )

virtual

Get the higher order cell in order to access the evaluation function.

void vtkSimpleCellTessellator::TessellateFace	(	vtkGenericAdaptorCell *	cell,
		vtkGenericAttributeCollection *	att,
		vtkIdType	index,
		vtkDoubleArray *	points,
		vtkCellArray *	cellArray,
		vtkPointData *	internalPd
	)

virtual

Tessellate a face of a 3D `cell'. The face is specified by the index value. The result is a set of smaller linear triangles in `cellArray' with `points' and point data `internalPd'.

Precondition: cell_exists: cell!=0; valid_dimension: cell->GetDimension()==3; valid_index_range: (index>=0) && (index<cell->GetNumberOfBoundaries(2)); att_exists: att!=0; points_exists: points!=0; cellArray_exists: cellArray!=0; internalPd_exists: internalPd!=0

Implements vtkGenericCellTessellator.

void vtkSimpleCellTessellator::Tessellate	(	vtkGenericAdaptorCell *	cell,
		vtkGenericAttributeCollection *	att,
		vtkDoubleArray *	points,
		vtkCellArray *	cellArray,
		vtkPointData *	internalPd
	)

virtual

Tessellate a 3D `cell'. The result is a set of smaller linear tetrahedra in `cellArray' with `points' and point data `internalPd'.

Precondition: cell_exists: cell!=0; valid_dimension: cell->GetDimension()==3; att_exists: att!=0; points_exists: points!=0; cellArray_exists: cellArray!=0; internalPd_exists: internalPd!=0

Implements vtkGenericCellTessellator.

void vtkSimpleCellTessellator::Triangulate	(	vtkGenericAdaptorCell *	cell,
		vtkGenericAttributeCollection *	att,
		vtkDoubleArray *	points,
		vtkCellArray *	cellArray,
		vtkPointData *	internalPd
	)

virtual

Triangulate a 2D `cell'. The result is a set of smaller linear triangles in `cellArray' with `points' and point data `internalPd'.

Precondition: cell_exists: cell!=0; valid_dimension: cell->GetDimension()==2; att_exists: att!=0; points_exists: points!=0; cellArray_exists: cellArray!=0; internalPd_exists: internalPd!=0

Implements vtkGenericCellTessellator.

void vtkSimpleCellTessellator::Reset ( )

Reset the output for repeated use of this class.

void vtkSimpleCellTessellator::Initialize ( vtkGenericDataSet * ds )

virtual

Initialize the tessellator with a data set `ds'.

Implements vtkGenericCellTessellator.

int vtkSimpleCellTessellator::GetFixedSubdivisions ( )

Return the number of fixed subdivisions. It is used to prevent from infinite loop in degenerated cases. For order 3 or higher, if the inflection point is exactly on the mid-point, error metric will not detect that a subdivision is required. 0 means no fixed subdivision: there will be only adaptive subdivisions. The algorithm first performs `GetFixedSubdivisions' non adaptive subdivisions followed by at most `GetMaxAdaptiveSubdivisions' adaptive subdivisions. Hence, there are at most `GetMaxSubdivisionLevel' subdivisions.

Postcondition: positive_result: result>=0 && result<=GetMaxSubdivisionLevel()

int vtkSimpleCellTessellator::GetMaxSubdivisionLevel ( )

Return the maximum level of subdivision. It is used to prevent from infinite loop in degenerated cases. For order 3 or higher, if the inflection point is exactly on the mid-point, error metric will not detect that a subdivision is required. 0 means no subdivision, neither fixed nor adaptive.

Postcondition: positive_result: result>=GetFixedSubdivisions()

int vtkSimpleCellTessellator::GetMaxAdaptiveSubdivisions ( )

Return the maximum number of adaptive subdivisions.

Postcondition: valid_result: result==GetMaxSubdivisionLevel()-GetFixedSubdivisions()

void vtkSimpleCellTessellator::SetFixedSubdivisions ( int level )

Set the number of fixed subdivisions. See GetFixedSubdivisions() for more explanations.

Precondition: positive_level: level>=0 && level<=GetMaxSubdivisionLevel()

Postcondition: is_set: GetFixedSubdivisions()==level

void vtkSimpleCellTessellator::SetMaxSubdivisionLevel ( int level )

Set the maximum level of subdivision. See GetMaxSubdivisionLevel() for more explanations.

Precondition: positive_level: level>=GetFixedSubdivisions()

Postcondition: is_set: level==GetMaxSubdivisionLevel()

void vtkSimpleCellTessellator::SetSubdivisionLevels	(	int	fixed,
		int	maxLevel
	)

Set both the number of fixed subdivisions and the maximum level of subdivisions. See GetFixedSubdivisions(), GetMaxSubdivisionLevel() and GetMaxAdaptiveSubdivisions() for more explanations.

Precondition: positive_fixed: fixed>=0; valid_range: fixed<=maxLevel

Postcondition: fixed_is_set: fixed==GetFixedSubdivisions(); maxLevel_is_set: maxLevel==GetMaxSubdivisionLevel()

void vtkSimpleCellTessellator::CopyPoint ( vtkIdType pointId )

protected

Extract point `pointId' from the edge table to the output point and output point data.

void vtkSimpleCellTessellator::InsertEdgesIntoEdgeTable ( vtkTriangleTile & tri )

protected

void vtkSimpleCellTessellator::RemoveEdgesFromEdgeTable ( vtkTriangleTile & tri )

protected

void vtkSimpleCellTessellator::InsertPointsIntoEdgeTable ( vtkTriangleTile & tri )

protected

void vtkSimpleCellTessellator::InsertEdgesIntoEdgeTable ( vtkTetraTile & tetra )

protected

void vtkSimpleCellTessellator::RemoveEdgesFromEdgeTable ( vtkTetraTile & tetra )

protected

void vtkSimpleCellTessellator::InitTetraTile	(	vtkTetraTile &	root,
		vtkIdType *	localIds,
		vtkIdType *	ids,
		int *	edgeIds,
		int *	faceIds
	)

protected

Initialize `root' with the sub-tetra defined by the `localIds' points on the complex cell, `ids' are the global ids over the mesh of those points. The sub-tetra is also defined by the ids of its edges and of its faces relative to the complex cell. -1 means that the edge or the face of the sub-tetra is not an original edge or face of the complex cell.

Precondition: cell_exists: this->GenericCell!=0; localIds_exists: localIds!=0; localIds_size: sizeof(localIds)==4; ids_exists: ids!=0; ids_size: sizeof(ids)==4; edgeIds_exists: edgeIds!=0; edgeIds_size: sizeof(edgeIds)==6; faceIds_exists: faceIds!=0; faceIds_size: sizeof(faceIds)==4

void vtkSimpleCellTessellator::TriangulateTriangle	(	vtkGenericAdaptorCell *	cell,
		vtkIdType *	localIds,
		vtkIdType *	ids,
		int *	edgeIds,
		vtkGenericAttributeCollection *	att,
		vtkDoubleArray *	points,
		vtkCellArray *	cellArray,
		vtkPointData *	internalPd
	)

protected

Triangulate a triangle of `cell'. This triangle can be the top-level triangle if the cell is a triangle or a toplevel sub-triangle is the cell is a polygon, or a triangular face of a 3D cell or a top-level sub-triangle of a face of a 3D cell if the face is not a triangle. Arguments `localIds', `ids' and `edgeIds' have the same meaning than for InitTetraTile.

Precondition: cell_exists: cell!=0; localIds_exists: localIds!=0; localIds_size: sizeof(localIds)==3; ids_exists: ids!=0; ids_size: sizeof(ids)==3; edgeIds_exists: edgeIds!=0; edgeIds_size: sizeof(edgeIds)==3

void vtkSimpleCellTessellator::AllocateScalars ( int size )

protected

Allocate some memory if Scalars does not exists or is smaller than size.

Precondition: positive_size: size>0

int vtkSimpleCellTessellator::FindEdgeReferenceCount	(	double	p1[3],
		double	p2[3],
		vtkIdType &	e1,
		vtkIdType &	e2
	)

protected

int vtkSimpleCellTessellator::GetNumberOfCellsUsingFace ( int faceId )

protected

int vtkSimpleCellTessellator::GetNumberOfCellsUsingEdge ( int edgeId )

protected

int vtkSimpleCellTessellator::IsEdgeOnFace	(	double	p1[3],
		double	p2[3]
	)

protected

Is the edge defined by vertices (`p1',`p2') in parametric coordinates on some edge of the original tetrahedron? If yes return on which edge it is, else return -1.

Precondition: p1!=p2; p1 and p2 are in bounding box (0,0,0) (1,1,1)

Postcondition: valid_result: (result==-1) || ( result>=0 && result<=5 )

int vtkSimpleCellTessellator::FindEdgeParent2D	(	double	p1[3],
		double	p2[3],
		int &	localId
	)

protected

Return 1 if the parent of edge defined by vertices (`p1',`p2') in parametric coordinates, is an edge; 3 if there is no parent (the edge is inside). If the parent is an edge, return its id in `localId'.

Precondition: p1!=p2; p1 and p2 are in bounding box (0,0,0) (1,1,1)

Postcondition: valid_result: (result==1)||(result==3)

int vtkSimpleCellTessellator::FindEdgeParent	(	double	p1[3],
		double	p2[3],
		int &	localId
	)

protected

Return 1 if the parent of edge defined by vertices (`p1',`p2') in parametric coordinates, is an edge; 2 if the parent is a face, 3 if there is no parent (the edge is inside). If the parent is an edge or a face, return its id in `localId'.

Precondition: p1!=p2; p1 and p2 are in bounding box (0,0,0) (1,1,1)

Postcondition: valid_result: result>=1 && result<=3

void vtkSimpleCellTessellator::AllocatePointIds ( int size )

protected

Allocate some memory if PointIds does not exist or is smaller than size.

Precondition: positive_size: size>0

int vtkSimpleCellTessellator::FacesAreEqual	(	int *	originalFace,
		int	face[3]
	)

protected

Are the faces `originalFace' and `face' equal? The result is independent from any order or orientation.

Precondition: originalFace_exists: originalFace!=0

Friends And Related Function Documentation

friend class vtkTetraTile

friend

Definition at line 354 of file vtkSimpleCellTessellator.h.

friend class vtkTriangleTile

friend

Definition at line 355 of file vtkSimpleCellTessellator.h.

Member Data Documentation

vtkGenericEdgeTable* vtkSimpleCellTessellator::EdgeTable

protected

HashTable instead of vtkPointLocator

Definition at line 189 of file vtkSimpleCellTessellator.h.

vtkGenericAdaptorCell* vtkSimpleCellTessellator::GenericCell

protected

To access the higher order cell from third party library

Definition at line 237 of file vtkSimpleCellTessellator.h.

double* vtkSimpleCellTessellator::Scalars

protected

Scalar buffer used to save the interpolate values of the attributes The capacity is at least the number of components of the attribute collection ot the current cell.

Definition at line 253 of file vtkSimpleCellTessellator.h.

int vtkSimpleCellTessellator::ScalarsCapacity

protected

Definition at line 254 of file vtkSimpleCellTessellator.h.

int vtkSimpleCellTessellator::PointOffset

protected

Number of double value to skip to go to the next point into Scalars array It is 6+attributeCollection->GetNumberOfComponents()

Definition at line 258 of file vtkSimpleCellTessellator.h.

vtkGenericCellIterator* vtkSimpleCellTessellator::CellIterator

protected

Used to iterate over edges boundaries in GetNumberOfCellsUsingEdges()

Definition at line 261 of file vtkSimpleCellTessellator.h.