helper class to perform cell tessellation More...

#include <vtkGenericCellTessellator.h>

Inheritance diagram for vtkGenericCellTessellator:

Collaboration diagram for vtkGenericCellTessellator:

Public Types
typedef vtkObject	Superclass

Public Member Functions
virtual vtkTypeBool	IsA (const char *type)
	Return 1 if this class is the same type of (or a subclass of) the named class. More...

vtkGenericCellTessellator *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent) override
	Methods invoked by print to print information about the object including superclasses. More...

virtual void	TessellateFace (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkIdType index, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)=0
	Tessellate a face of a 3D `cell'. More...

virtual void	Tessellate (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)=0
	Tessellate a 3D `cell'. More...

virtual void	Triangulate (vtkGenericAdaptorCell cell, vtkGenericAttributeCollection att, vtkDoubleArray points, vtkCellArray cellArray, vtkPointData *internalPd)=0
	Triangulate a 2D `cell'. More...

virtual void	Initialize (vtkGenericDataSet *ds)=0
	Initialize the tessellator with a data set `ds'. More...

void	InitErrorMetrics (vtkGenericDataSet *ds)
	Init the error metric with the dataset. More...

void	GetMaxErrors (double *errors)
	Get the maximum error measured after the fixed subdivision. More...


virtual void	SetErrorMetrics (vtkCollection *someErrorMetrics)
	Specify the list of error metrics used to decide if an edge has to be split or not. More...

virtual vtkCollection *	GetErrorMetrics ()
	Specify the list of error metrics used to decide if an edge has to be split or not. More...


virtual int	GetMeasurement ()
	If true, measure the quality of the fixed subdivision. More...

virtual void	SetMeasurement (int)
	If true, measure the quality of the fixed subdivision. More...

Public Member Functions inherited from vtkObject
	vtkBaseTypeMacro (vtkObject, vtkObjectBase)

virtual void	DebugOn ()
	Turn debugging output on. More...

virtual void	DebugOff ()
	Turn debugging output off. More...

bool	GetDebug ()
	Get the value of the debug flag. More...

void	SetDebug (bool debugFlag)
	Set the value of the debug flag. More...

virtual void	Modified ()
	Update the modification time for this object. More...

virtual vtkMTimeType	GetMTime ()
	Return this object's modified time. More...

void	RemoveObserver (unsigned long tag)

void	RemoveObservers (unsigned long event)

void	RemoveObservers (const char *event)

void	RemoveAllObservers ()

vtkTypeBool	HasObserver (unsigned long event)

vtkTypeBool	HasObserver (const char *event)

int	InvokeEvent (unsigned long event)

int	InvokeEvent (const char *event)

unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

unsigned long	AddObserver (const char event, vtkCommand , float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkCommand *	GetCommand (unsigned long tag)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObserver (vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObservers (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

void	RemoveObservers (const char event, vtkCommand )
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkTypeBool	HasObserver (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

vtkTypeBool	HasObserver (const char event, vtkCommand )
	Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)
	Allow user to set the AbortFlagOn() with the return value of the callback method. More...

int	InvokeEvent (unsigned long event, void *callData)
	This method invokes an event and return whether the event was aborted or not. More...

int	InvokeEvent (const char event, void callData)
	This method invokes an event and return whether the event was aborted or not. More...

Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const
	Return the class name as a string. More...

virtual void	Delete ()
	Delete a VTK object. More...

virtual void	FastDelete ()
	Delete a reference to this object. More...

void	InitializeObjectBase ()

void	Print (ostream &os)
	Print an object to an ostream. More...

virtual void	Register (vtkObjectBase *o)
	Increase the reference count (mark as used by another object). More...

virtual void	UnRegister (vtkObjectBase *o)
	Decrease the reference count (release by another object). More...

int	GetReferenceCount ()
	Return the current reference count of this object. More...

void	SetReferenceCount (int)
	Sets the reference count. More...

void	PrintRevisions (ostream &)
	Legacy. More...

virtual void	PrintHeader (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses. More...

virtual void	PrintTrailer (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses. More...

Static Public Member Functions
static vtkTypeBool	IsTypeOf (const char *type)

static vtkGenericCellTessellator *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkObject
static vtkObject *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...

static void	BreakOnError ()
	This method is called when vtkErrorMacro executes. More...

static void	SetGlobalWarningDisplay (int val)
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static void	GlobalWarningDisplayOn ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static void	GlobalWarningDisplayOff ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

static int	GetGlobalWarningDisplay ()
	This is a global flag that controls whether any debug, warning or error messages are displayed. More...

Static Public Member Functions inherited from vtkObjectBase
static vtkTypeBool	IsTypeOf (const char *name)
	Return 1 if this class type is the same type of (or a subclass of) the named class. More...

static vtkObjectBase *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkGenericCellTessellator ()

	~vtkGenericCellTessellator () override

int	RequiresEdgeSubdivision (double left, double mid, double *right, double alpha)
	Does the edge need to be subdivided according to at least one error metric? The edge is defined by its `leftPoint' and its `rightPoint'. More...

virtual void	UpdateMaxError (double leftPoint, double midPoint, double *rightPoint, double alpha)
	Update the max error of each error metric according to the error at the mid-point. More...

void	ResetMaxErrors ()
	Reset the maximal error of each error metric. More...

void	SetGenericCell (vtkGenericAdaptorCell *cell)
	Send the current cell to error metrics. More...

Protected Member Functions inherited from vtkObject
	vtkObject ()

	~vtkObject () override

void	RegisterInternal (vtkObjectBase *, vtkTypeBool check) override

void	UnRegisterInternal (vtkObjectBase *, vtkTypeBool check) override

void	InternalGrabFocus (vtkCommand mouseEvents, vtkCommand keypressEvents=nullptr)
	These methods allow a command to exclusively grab all events. More...

void	InternalReleaseFocus ()
	These methods allow a command to exclusively grab all events. More...

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
vtkCollection *	ErrorMetrics
	List of error metrics. More...

vtkGenericDataSet *	DataSet
	Dataset to be tessellated. More...

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

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, 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 by considering the relative value of the point ids.

Definition at line 58 of file vtkGenericCellTessellator.h.

Member Typedef Documentation

typedef vtkObject vtkGenericCellTessellator::Superclass

Definition at line 61 of file vtkGenericCellTessellator.h.

Constructor & Destructor Documentation

vtkGenericCellTessellator::vtkGenericCellTessellator ( )

protected

vtkGenericCellTessellator::~vtkGenericCellTessellator ( )

overrideprotected

Member Function Documentation

static vtkTypeBool vtkGenericCellTessellator::IsTypeOf ( const char * type )

static

virtual vtkTypeBool vtkGenericCellTessellator::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 vtkObjectBase.

Reimplemented in vtkSimpleCellTessellator.

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

static

virtual vtkObjectBase* vtkGenericCellTessellator::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented in vtkSimpleCellTessellator.

vtkGenericCellTessellator* vtkGenericCellTessellator::NewInstance ( ) const

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

overridevirtual

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.

Reimplemented in vtkSimpleCellTessellator.

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

pure 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

Implemented in vtkSimpleCellTessellator.

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

pure 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

Implemented in vtkSimpleCellTessellator.

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

pure 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

Implemented in vtkSimpleCellTessellator.

virtual void vtkGenericCellTessellator::SetErrorMetrics ( vtkCollection * someErrorMetrics )

virtual

Specify the list of error metrics used to decide if an edge has to be split or not.

It is a collection of vtkGenericSubdivisionErrorMetric-s.

virtual vtkCollection* vtkGenericCellTessellator::GetErrorMetrics ( )

virtual

Specify the list of error metrics used to decide if an edge has to be split or not.

It is a collection of vtkGenericSubdivisionErrorMetric-s.

virtual void vtkGenericCellTessellator::Initialize ( vtkGenericDataSet * ds )

pure virtual

Initialize the tessellator with a data set `ds'.

Implemented in vtkSimpleCellTessellator.

void vtkGenericCellTessellator::InitErrorMetrics ( vtkGenericDataSet * ds )

Init the error metric with the dataset.

Should be called in each filter before any tessellation of any cell.

virtual int vtkGenericCellTessellator::GetMeasurement ( )

virtual

If true, measure the quality of the fixed subdivision.

virtual void vtkGenericCellTessellator::SetMeasurement ( int )

virtual

If true, measure the quality of the fixed subdivision.

void vtkGenericCellTessellator::GetMaxErrors ( double * errors )

Get the maximum error measured after the fixed subdivision.

Precondition: errors_exists: errors!=0; valid_size: sizeof(errors)==GetErrorMetrics()->GetNumberOfItems()

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

protected

Does the edge need to be subdivided according to at least one error metric? The edge is defined by its `leftPoint' and its `rightPoint'.

`leftPoint', `midPoint' and `rightPoint' have to be initialized before calling RequiresEdgeSubdivision(). Their format is global coordinates, parametric coordinates and point centered attributes: xyx rst abc de... `alpha' is the normalized abscissa of the midpoint along the edge. (close to 0 means close to the left point, close to 1 means close to the right point)

Precondition: leftPoint_exists: leftPoint!=0; midPoint_exists: midPoint!=0; rightPoint_exists: rightPoint!=0; clamped_alpha: alpha>0 && alpha<1; valid_size: sizeof(leftPoint)=sizeof(midPoint)=sizeof(rightPoint) =GetAttributeCollection()->GetNumberOfPointCenteredComponents()+6

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

protectedvirtual

Update the max error of each error metric according to the error at the mid-point.

The type of error depends on the state of the concrete error metric. For instance, it can return an absolute or relative error metric. See RequiresEdgeSubdivision() for a description of the arguments.

Precondition: leftPoint_exists: leftPoint!=0; midPoint_exists: midPoint!=0; rightPoint_exists: rightPoint!=0; clamped_alpha: alpha>0 && alpha<1; valid_size: sizeof(leftPoint)=sizeof(midPoint)=sizeof(rightPoint) =GetAttributeCollection()->GetNumberOfPointCenteredComponents()+6

void vtkGenericCellTessellator::ResetMaxErrors ( )

protected

Reset the maximal error of each error metric.

The purpose of the maximal error is to measure the quality of a fixed subdivision.

void vtkGenericCellTessellator::SetGenericCell ( vtkGenericAdaptorCell * cell )

protected

Send the current cell to error metrics.

Should be called at the beginning of the implementation of Tessellate(), Triangulate() or TessellateFace()