vtkGenericCellTessellator Class Reference

#include <vtkGenericCellTessellator.h>

Inheritance diagram for vtkGenericCellTessellator:

[legend]Collaboration diagram for vtkGenericCellTessellator:

[legend]List of all members.

Detailed Description

helper class to perform cell tessellation

vtkGenericCellTessellator 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.

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

Created by:

Bertel, Francois

CVS contributions (if > 5%):

Bertel, Francois (99%)

CVS logs (CVSweb):

.cxx (/Filtering/vtkGenericCellTessellator.cxx)
.h (/Filtering/vtkGenericCellTessellator.h)

Tests:: vtkGenericCellTessellator (Tests)

Definition at line 70 of file vtkGenericCellTessellator.h.

[NOHEADER]

void InsertEdgesIntoEdgeTable (vtkTriangleTile &tri)

void RemoveEdgesFromEdgeTable (vtkTriangleTile &tri)

void InsertPointsIntoEdgeTable (vtkTriangleTile &tri)

vtkGenericEdgeTable * EdgeTable

Public Types

typedef vtkObject Superclass

Public Member Functions

virtual const char * GetClassName ()

virtual int IsA (const char *type)

void PrintSelf (ostream &os, vtkIndent indent)

void Reset ()

void Initialize (vtkIdType numPts)

vtkGenericEdgeTable * GetEdgeTable ()

virtual vtkGenericAdaptorCell * GetGenericCell ()

virtual void TessellateTriangleFace (vtkGenericAdaptorCell *cell, vtkGenericAttributeCollection *att, vtkIdType index, vtkDoubleArray *points, vtkCellArray *cellArray, vtkDoubleArray *scalars)

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

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

virtual void SetErrorMetric (vtkGenericSubdivisionErrorMetric *subAlgorithm)

virtual vtkGenericSubdivisionErrorMetric * GetErrorMetric ()

Static Public Member Functions

vtkGenericCellTessellator * New ()

int IsTypeOf (const char *type)

vtkGenericCellTessellator * SafeDownCast (vtkObject *o)

Protected Member Functions

vtkGenericCellTessellator ()

~vtkGenericCellTessellator ()

void InsertEdgesIntoEdgeTable (vtkTetraTile &tetra)

void RemoveEdgesFromEdgeTable (vtkTetraTile &tetra)

void InsertPointsIntoEdgeTable (vtkTetraTile &tetra)

void InternalTessellateTriangle (vtkTriangleTile &root)

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)

Protected Attributes

vtkGenericAdaptorCell * GenericCell

vtkGenericCellIterator * CellIterator

vtkGenericAttributeCollection * AttributeCollection

vtkGenericSubdivisionErrorMetric * ErrorMetric

double * Scalars

int ScalarsCapacity

vtkDoubleArray * TessellatePoints

vtkCellArray * TessellateCellArray

vtkDoubleArray * TessellateScalars

Member Typedef Documentation

typedef vtkObject vtkGenericCellTessellator::Superclass

Reimplemented from vtkObject.
Definition at line 74 of file vtkGenericCellTessellator.h.

Constructor & Destructor Documentation

vtkGenericCellTessellator::vtkGenericCellTessellator ( ) [protected]

vtkGenericCellTessellator::~vtkGenericCellTessellator ( ) [protected]

Member Function Documentation

vtkGenericCellTessellator* vtkGenericCellTessellator::New ( ) [static]

Create an object with Debug turned off, modified time initialized to zero, and reference counting on.
Reimplemented from vtkObject.

virtual const char* vtkGenericCellTessellator::GetClassName ( ) [virtual]

Reimplemented from vtkObject.

int vtkGenericCellTessellator::IsTypeOf ( const char * type ) [static]

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

virtual int vtkGenericCellTessellator::IsA ( const char * type ) [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 vtkTypeRevisionMacro found in vtkSetGet.h.
Reimplemented from vtkObject.

vtkGenericCellTessellator* vtkGenericCellTessellator::SafeDownCast ( vtkObject * o ) [static]

Reimplemented from vtkObject.

void vtkGenericCellTessellator::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 vtkObject.

virtual vtkGenericAdaptorCell* vtkGenericCellTessellator::GetGenericCell ( ) [virtual]

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

virtual void vtkGenericCellTessellator::TessellateTriangleFace ( vtkGenericAdaptorCell * cell,

vtkGenericAttributeCollection * att,

vtkIdType index,

vtkDoubleArray * points,

vtkCellArray * cellArray,

vtkDoubleArray * scalars

) [virtual]

Tessellate a face of a tetrahedron cell. The face is specified by the index value.
Precondition:
cell_exists: cell!=0
is_a_tetra: (cell->GetType()==VTK_TETRA) ||(cell->GetType()==VTK_QUADRATIC_TETRA) ||(cell->GetType()==VTK_HIGHER_ORDER_TETRAHEDRON)
valid_index_range: (index>=0) && (index<4)

void vtkGenericCellTessellator::Tessellate ( vtkGenericAdaptorCell * cell,

vtkGenericAttributeCollection * att,

vtkDoubleArray * points,

vtkCellArray * cellArray,

vtkDoubleArray * scalars

)

Tessellate a tetrahedron `cell'. The result is a set of smaller linear cells `cellArray' with `points' and point data `scalars'.
Precondition:
cell_exists: cell!=0
is_a_tetra: (cell->GetType()==VTK_TETRA) ||(cell->GetType()==VTK_QUADRATIC_TETRA) ||(cell->GetType()==VTK_HIGHER_ORDER_TETRAHEDRON)

void vtkGenericCellTessellator::Triangulate ( vtkGenericAdaptorCell * cell,

vtkGenericAttributeCollection * att,

vtkDoubleArray * points,

vtkCellArray * cellArray,

vtkDoubleArray * scalars

)

Triangulate a triangle `cell'.
Precondition:
cell_exists: cell!=0
is_a_triangle: (cell->GetType()==VTK_TRIANGLE) ||(cell->GetType()==VTK_QUADRATIC_TRIANGLE) ||(cell->GetType()==VTK_HIGHER_ORDER_TRIANGLE)

virtual void vtkGenericCellTessellator::SetErrorMetric ( vtkGenericSubdivisionErrorMetric * subAlgorithm ) [virtual]

Specify the object to use to compute the error metric.

virtual vtkGenericSubdivisionErrorMetric* vtkGenericCellTessellator::GetErrorMetric ( ) [virtual]

Specify the object to use to compute the error metric.

void vtkGenericCellTessellator::Reset ( )

Reset the output for repeated use of this class.

void vtkGenericCellTessellator::Initialize ( vtkIdType numPts )

Initialize the internal hash table.

vtkGenericEdgeTable* vtkGenericCellTessellator::GetEdgeTable ( )

Return the internal edge table.

void vtkGenericCellTessellator::InsertEdgesIntoEdgeTable ( vtkTriangleTile & tri ) [protected]

void vtkGenericCellTessellator::RemoveEdgesFromEdgeTable ( vtkTriangleTile & tri ) [protected]

void vtkGenericCellTessellator::InsertPointsIntoEdgeTable ( vtkTriangleTile & tri ) [protected]

void vtkGenericCellTessellator::InsertEdgesIntoEdgeTable ( vtkTetraTile & tetra ) [protected]

void vtkGenericCellTessellator::RemoveEdgesFromEdgeTable ( vtkTetraTile & tetra ) [protected]

void vtkGenericCellTessellator::InsertPointsIntoEdgeTable ( vtkTetraTile & tetra ) [protected]

void vtkGenericCellTessellator::InternalTessellateTriangle ( vtkTriangleTile & root ) [protected]

Internal function used to tessellate a triangle

int vtkGenericCellTessellator::FindEdgeReferenceCount ( double p1[3],

double p2[3],

vtkIdType & e1,

vtkIdType & e2

) [protected]

int vtkGenericCellTessellator::GetNumberOfCellsUsingFace ( int faceId ) [protected]

int vtkGenericCellTessellator::GetNumberOfCellsUsingEdge ( int edgeId ) [protected]

int vtkGenericCellTessellator::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 vtkGenericCellTessellator::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 vtkGenericCellTessellator::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

Member Data Documentation

vtkGenericEdgeTable* vtkGenericCellTessellator::EdgeTable [protected]

HashTable instead of vtkPointLocator
Definition at line 142 of file vtkGenericCellTessellator.h.

vtkGenericAdaptorCell* vtkGenericCellTessellator::GenericCell [protected]

To access the higher order cell from third party library
Definition at line 153 of file vtkGenericCellTessellator.h.

double* vtkGenericCellTessellator::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 159 of file vtkGenericCellTessellator.h.

int vtkGenericCellTessellator::ScalarsCapacity [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 160 of file vtkGenericCellTessellator.h.

vtkGenericCellIterator* vtkGenericCellTessellator::CellIterator [protected]

Used to iterate over edges boundaries in GetNumberOfCellsUsingEdges()
Definition at line 164 of file vtkGenericCellTessellator.h.

vtkGenericAttributeCollection* vtkGenericCellTessellator::AttributeCollection [protected]

To access the higher order field from third party library
Definition at line 167 of file vtkGenericCellTessellator.h.

vtkDoubleArray* vtkGenericCellTessellator::TessellatePoints [protected]

To avoid New/Delete
Definition at line 171 of file vtkGenericCellTessellator.h.

vtkCellArray* vtkGenericCellTessellator::TessellateCellArray [protected]

To avoid New/Delete
Definition at line 172 of file vtkGenericCellTessellator.h.

vtkDoubleArray* vtkGenericCellTessellator::TessellateScalars [protected]

To avoid New/Delete
Definition at line 173 of file vtkGenericCellTessellator.h.

vtkGenericSubdivisionErrorMetric* vtkGenericCellTessellator::ErrorMetric [protected]

Contains the error metric
Definition at line 177 of file vtkGenericCellTessellator.h.

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

dox/Filtering/vtkGenericCellTessellator.h


[NOHEADER]
void	InsertEdgesIntoEdgeTable (vtkTriangleTile &tri)
void	RemoveEdgesFromEdgeTable (vtkTriangleTile &tri)
void	InsertPointsIntoEdgeTable (vtkTriangleTile &tri)
vtkGenericEdgeTable *	EdgeTable
Public Types
typedef vtkObject	Superclass
Public Member Functions
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
void	Reset ()
void	Initialize (vtkIdType numPts)
vtkGenericEdgeTable *	GetEdgeTable ()

virtual vtkGenericAdaptorCell *	GetGenericCell ()

virtual void	TessellateTriangleFace (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkIdType index, vtkDoubleArray points, vtkCellArray cellArray, vtkDoubleArray *scalars)

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

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

virtual void	SetErrorMetric (vtkGenericSubdivisionErrorMetric *subAlgorithm)
virtual vtkGenericSubdivisionErrorMetric *	GetErrorMetric ()
Static Public Member Functions
vtkGenericCellTessellator *	New ()
int	IsTypeOf (const char *type)
vtkGenericCellTessellator *	SafeDownCast (vtkObject *o)
Protected Member Functions
	vtkGenericCellTessellator ()
	~vtkGenericCellTessellator ()
void	InsertEdgesIntoEdgeTable (vtkTetraTile &tetra)
void	RemoveEdgesFromEdgeTable (vtkTetraTile &tetra)
void	InsertPointsIntoEdgeTable (vtkTetraTile &tetra)
void	InternalTessellateTriangle (vtkTriangleTile &root)
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)
Protected Attributes
vtkGenericAdaptorCell *	GenericCell
vtkGenericCellIterator *	CellIterator
vtkGenericAttributeCollection *	AttributeCollection
vtkGenericSubdivisionErrorMetric *	ErrorMetric

double *	Scalars
int	ScalarsCapacity

vtkDoubleArray *	TessellatePoints
vtkCellArray *	TessellateCellArray
vtkDoubleArray *	TessellateScalars