reduce the number of triangles in a mesh More...

#include <vtkQuadricDecimation.h>

Inheritance diagram for vtkQuadricDecimation:

Collaboration diagram for vtkQuadricDecimation:

Classes
struct	ErrorQuadric

Public Types
typedef vtkPolyDataAlgorithm	Superclass

Public Types inherited from vtkPolyDataAlgorithm
typedef vtkAlgorithm	Superclass

Public Types inherited from vtkAlgorithm
typedef vtkObject	Superclass

enum	DesiredOutputPrecision { SINGLE_PRECISION, DOUBLE_PRECISION, DEFAULT_PRECISION }

Public Types inherited from vtkObject
typedef vtkObjectBase	Superclass

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

vtkQuadricDecimation *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent)


virtual void	SetTargetReduction (double)

virtual double	GetTargetReduction ()


virtual void	SetAttributeErrorMetric (int)

virtual int	GetAttributeErrorMetric ()

virtual void	AttributeErrorMetricOn ()

virtual void	AttributeErrorMetricOff ()


virtual void	SetScalarsAttribute (int)

virtual int	GetScalarsAttribute ()

virtual void	ScalarsAttributeOn ()

virtual void	ScalarsAttributeOff ()

virtual void	SetVectorsAttribute (int)

virtual int	GetVectorsAttribute ()

virtual void	VectorsAttributeOn ()

virtual void	VectorsAttributeOff ()

virtual void	SetNormalsAttribute (int)

virtual int	GetNormalsAttribute ()

virtual void	NormalsAttributeOn ()

virtual void	NormalsAttributeOff ()

virtual void	SetTCoordsAttribute (int)

virtual int	GetTCoordsAttribute ()

virtual void	TCoordsAttributeOn ()

virtual void	TCoordsAttributeOff ()

virtual void	SetTensorsAttribute (int)

virtual int	GetTensorsAttribute ()

virtual void	TensorsAttributeOn ()

virtual void	TensorsAttributeOff ()


virtual void	SetScalarsWeight (double)

virtual void	SetVectorsWeight (double)

virtual void	SetNormalsWeight (double)

virtual void	SetTCoordsWeight (double)

virtual void	SetTensorsWeight (double)

virtual double	GetScalarsWeight ()

virtual double	GetVectorsWeight ()

virtual double	GetNormalsWeight ()

virtual double	GetTCoordsWeight ()

virtual double	GetTensorsWeight ()


virtual double	GetActualReduction ()

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

vtkDataObject *	GetInput ()

vtkDataObject *	GetInput (int port)

vtkPolyData *	GetPolyDataInput (int port)

vtkPolyData *	GetOutput ()

vtkPolyData *	GetOutput (int)

virtual void	SetOutput (vtkDataObject *d)

virtual int	ProcessRequest (vtkInformation , vtkInformationVector , vtkInformationVector )

void	SetInputData (vtkDataObject *)

void	SetInputData (int, vtkDataObject *)

void	AddInputData (vtkDataObject *)

void	AddInputData (int, vtkDataObject *)

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

int	HasExecutive ()

vtkExecutive *	GetExecutive ()

virtual void	SetExecutive (vtkExecutive *executive)

virtual int	ModifyRequest (vtkInformation *request, int when)

vtkInformation *	GetInputPortInformation (int port)

vtkInformation *	GetOutputPortInformation (int port)

int	GetNumberOfInputPorts ()

int	GetNumberOfOutputPorts ()

void	UpdateProgress (double amount)

vtkInformation *	GetInputArrayInformation (int idx)

void	RemoveAllInputs ()

vtkDataObject *	GetOutputDataObject (int port)

virtual void	RemoveInputConnection (int port, vtkAlgorithmOutput *input)

virtual void	RemoveInputConnection (int port, int idx)

virtual void	RemoveAllInputConnections (int port)

int	GetNumberOfInputConnections (int port)

int	GetTotalNumberOfInputConnections ()

vtkAlgorithmOutput *	GetInputConnection (int port, int index)

vtkAlgorithm *	GetInputAlgorithm (int port, int index, int &algPort)

vtkAlgorithm *	GetInputAlgorithm (int port, int index)

vtkExecutive *	GetInputExecutive (int port, int index)

vtkInformation *	GetInputInformation (int port, int index)

vtkInformation *	GetOutputInformation (int port)

virtual void	UpdateInformation ()

virtual void	UpdateDataObject ()

virtual void	PropagateUpdateExtent ()

virtual void	UpdateWholeExtent ()

void	ConvertTotalInputToPortConnection (int ind, int &port, int &conn)

int	SetUpdateExtentToWholeExtent (int port)

int	SetUpdateExtentToWholeExtent ()

void	SetUpdateExtent (int port, int extent[6])

int	ProcessRequest (vtkInformation request, vtkCollection inInfo, vtkInformationVector *outInfo)

virtual int	ComputePipelineMTime (vtkInformation request, vtkInformationVector inInfoVec, vtkInformationVector outInfoVec, int requestFromOutputPort, unsigned long *mtime)

virtual vtkInformation *	GetInformation ()

virtual void	SetInformation (vtkInformation *)

virtual void	Register (vtkObjectBase *o)

virtual void	UnRegister (vtkObjectBase *o)

virtual void	SetAbortExecute (int)

virtual int	GetAbortExecute ()

virtual void	AbortExecuteOn ()

virtual void	AbortExecuteOff ()

virtual void	SetProgress (double)

virtual double	GetProgress ()

void	SetProgressText (const char *ptext)

virtual char *	GetProgressText ()

virtual unsigned long	GetErrorCode ()

virtual void	SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, const char *name)

virtual void	SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, int fieldAttributeType)

virtual void	SetInputArrayToProcess (int idx, vtkInformation *info)

virtual void	SetInputArrayToProcess (int idx, int port, int connection, const char fieldAssociation, const char attributeTypeorName)

vtkDataObject *	GetInputDataObject (int port, int connection)

virtual void	SetInputConnection (int port, vtkAlgorithmOutput *input)

virtual void	SetInputConnection (vtkAlgorithmOutput *input)

virtual void	AddInputConnection (int port, vtkAlgorithmOutput *input)

virtual void	AddInputConnection (vtkAlgorithmOutput *input)

virtual void	SetInputDataObject (int port, vtkDataObject *data)

virtual void	SetInputDataObject (vtkDataObject *data)

virtual void	AddInputDataObject (int port, vtkDataObject *data)

virtual void	AddInputDataObject (vtkDataObject *data)

vtkAlgorithmOutput *	GetOutputPort (int index)

vtkAlgorithmOutput *	GetOutputPort ()

vtkAlgorithm *	GetInputAlgorithm ()

vtkExecutive *	GetInputExecutive ()

vtkInformation *	GetInputInformation ()

virtual void	Update (int port)

virtual void	Update ()

virtual void	SetReleaseDataFlag (int)

virtual int	GetReleaseDataFlag ()

void	ReleaseDataFlagOn ()

void	ReleaseDataFlagOff ()

int	UpdateExtentIsEmpty (vtkInformation pinfo, vtkDataObject output)

int	UpdateExtentIsEmpty (vtkInformation *pinfo, int extentType)

void	SetUpdateExtent (int port, int piece, int numPieces, int ghostLevel)

void	SetUpdateExtent (int piece, int numPieces, int ghostLevel)

void	SetUpdateExtent (int extent[6])

int *	GetUpdateExtent ()

int *	GetUpdateExtent (int port)

void	GetUpdateExtent (int &x0, int &x1, int &y0, int &y1, int &z0, int &z1)

void	GetUpdateExtent (int port, int &x0, int &x1, int &y0, int &y1, int &z0, int &z1)

void	GetUpdateExtent (int extent[6])

void	GetUpdateExtent (int port, int extent[6])

int	GetUpdatePiece ()

int	GetUpdatePiece (int port)

int	GetUpdateNumberOfPieces ()

int	GetUpdateNumberOfPieces (int port)

int	GetUpdateGhostLevel ()

int	GetUpdateGhostLevel (int port)

void	SetProgressObserver (vtkProgressObserver *)

virtual vtkProgressObserver *	GetProgressObserver ()

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)

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 int	IsTypeOf (const char *type)

static vtkQuadricDecimation *	SafeDownCast (vtkObjectBase *o)

static vtkQuadricDecimation *	New ()

Static Public Member Functions inherited from vtkPolyDataAlgorithm
static vtkPolyDataAlgorithm *	New ()

static int	IsTypeOf (const char *type)

static vtkPolyDataAlgorithm *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkAlgorithm
static vtkAlgorithm *	New ()

static int	IsTypeOf (const char *type)

static vtkAlgorithm *	SafeDownCast (vtkObjectBase *o)

static vtkInformationIntegerKey *	INPUT_IS_OPTIONAL ()

static vtkInformationIntegerKey *	INPUT_IS_REPEATABLE ()

static vtkInformationInformationVectorKey *	INPUT_REQUIRED_FIELDS ()

static vtkInformationStringVectorKey *	INPUT_REQUIRED_DATA_TYPE ()

static vtkInformationInformationVectorKey *	INPUT_ARRAYS_TO_PROCESS ()

static vtkInformationIntegerKey *	INPUT_PORT ()

static vtkInformationIntegerKey *	INPUT_CONNECTION ()

static vtkInformationIntegerKey *	CAN_PRODUCE_SUB_EXTENT ()

static vtkInformationIntegerKey *	CAN_HANDLE_PIECE_REQUEST ()

static void	SetDefaultExecutivePrototype (vtkExecutive *proto)

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

	vtkQuadricDecimation ()

	~vtkQuadricDecimation ()

int	RequestData (vtkInformation , vtkInformationVector , vtkInformationVector )

int	CollapseEdge (vtkIdType pt0Id, vtkIdType pt1Id)

void	InitializeQuadrics (vtkIdType numPts)

void	AddBoundaryConstraints (void)

void	ComputeQuadric (vtkIdType pointId)

void	AddQuadric (vtkIdType oldPtId, vtkIdType newPtId)

void	FindAffectedEdges (vtkIdType p1Id, vtkIdType p2Id, vtkIdList *edges)

vtkIdType	GetEdgeCellId (vtkIdType p1Id, vtkIdType p2Id)

int	IsGoodPlacement (vtkIdType pt0Id, vtkIdType pt1Id, const double *x)

int	TrianglePlaneCheck (const double t0[3], const double t1[3], const double t2[3], const double *x)

void	ComputeNumberOfComponents (void)

void	UpdateEdgeData (vtkIdType ptoId, vtkIdType pt1Id)

void	GetAttributeComponents ()


double	ComputeCost (vtkIdType edgeId, double *x)

double	ComputeCost2 (vtkIdType edgeId, double *x)


void	SetPointAttributeArray (vtkIdType ptId, const double *x)

void	GetPointAttributeArray (vtkIdType ptId, double *x)

Protected Member Functions inherited from vtkPolyDataAlgorithm
	vtkPolyDataAlgorithm ()

	~vtkPolyDataAlgorithm ()

virtual int	RequestInformation (vtkInformation request, vtkInformationVector inputVector, vtkInformationVector outputVector)

virtual int	FillOutputPortInformation (int port, vtkInformation *info)

virtual int	FillInputPortInformation (int port, vtkInformation *info)

virtual int	RequestUpdateExtent (vtkInformation , vtkInformationVector , vtkInformationVector )

Protected Member Functions inherited from vtkAlgorithm
	vtkAlgorithm ()

	~vtkAlgorithm ()

virtual void	SetNumberOfInputPorts (int n)

virtual void	SetNumberOfOutputPorts (int n)

int	InputPortIndexInRange (int index, const char *action)

int	OutputPortIndexInRange (int index, const char *action)

int	GetInputArrayAssociation (int idx, vtkInformationVector **inputVector)

virtual vtkExecutive *	CreateDefaultExecutive ()

virtual void	ReportReferences (vtkGarbageCollector *)

virtual void	SetNumberOfInputConnections (int port, int n)

int	GetInputArrayAssociation (int idx, int connection, vtkInformationVector **inputVector)

int	GetInputArrayAssociation (int idx, vtkDataObject *input)

vtkDataArray *	GetInputArrayToProcess (int idx, vtkInformationVector **inputVector)

vtkDataArray *	GetInputArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)

vtkDataArray *	GetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)

vtkDataArray *	GetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)

vtkDataArray *	GetInputArrayToProcess (int idx, vtkDataObject *input)

vtkDataArray *	GetInputArrayToProcess (int idx, vtkDataObject *input, int &association)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, vtkDataObject *input)

vtkAbstractArray *	GetInputAbstractArrayToProcess (int idx, vtkDataObject *input, int &association)

vtkInformation *	GetInputArrayFieldInformation (int idx, vtkInformationVector **inputVector)

virtual void	SetNthInputConnection (int port, int index, vtkAlgorithmOutput *input)

void	SetInputDataInternal (int port, vtkDataObject *input)

void	AddInputDataInternal (int port, vtkDataObject *input)

virtual void	SetErrorCode (unsigned long)

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 &)

	vtkObjectBase (const vtkObjectBase &)

void	operator= (const vtkObjectBase &)

Protected Attributes
double	TargetReduction

double	ActualReduction

int	AttributeErrorMetric

int	ScalarsAttribute

int	VectorsAttribute

int	NormalsAttribute

int	TCoordsAttribute

int	TensorsAttribute

double	ScalarsWeight

double	VectorsWeight

double	NormalsWeight

double	TCoordsWeight

double	TensorsWeight

int	NumberOfEdgeCollapses

vtkEdgeTable *	Edges

vtkIdList *	EndPoint1List

vtkIdList *	EndPoint2List

vtkPriorityQueue *	EdgeCosts

vtkDoubleArray *	TargetPoints

int	NumberOfComponents

vtkPolyData *	Mesh

ErrorQuadric *	ErrorQuadrics

int	AttributeComponents [6]

double	AttributeScale [6]

vtkIdList *	CollapseCellIds

double *	TempX

double *	TempQuad

double *	TempB

double **	TempA

double *	TempData

Protected Attributes inherited from vtkAlgorithm
vtkInformation *	Information

double	Progress

char *	ProgressText

vtkProgressObserver *	ProgressObserver

unsigned long	ErrorCode

Protected Attributes inherited from vtkObject
bool	Debug

vtkTimeStamp	MTime

vtkSubjectHelper *	SubjectHelper

Protected Attributes inherited from vtkObjectBase
vtkAtomicInt32	ReferenceCount

vtkWeakPointerBase **	WeakPointers

Additional Inherited Members
Public Attributes inherited from vtkAlgorithm
int	AbortExecute

Static Protected Member Functions inherited from vtkAlgorithm
static vtkInformationIntegerKey *	PORT_REQUIREMENTS_FILLED ()

Static Protected Attributes inherited from vtkAlgorithm
static vtkExecutive *	DefaultExecutivePrototype

Detailed Description

reduce the number of triangles in a mesh

vtkQuadricDecimation is a filter to reduce the number of triangles in a triangle mesh, forming a good approximation to the original geometry. The input to vtkQuadricDecimation is a vtkPolyData object, and only triangles are treated. If you desire to decimate polygonal meshes, first triangulate the polygons with vtkTriangleFilter.

The algorithm is based on repeated edge collapses until the requested mesh reduction is achieved. Edges are placed in a priority queue based on the "cost" to delete the edge. The cost is an approximate measure of error (distance to the original surface)–described by the so-called quadric error measure. The quadric error measure is associated with each vertex of the mesh and represents a matrix of planes incident on that vertex. The distance of the planes to the vertex is the error in the position of the vertex (originally the vertex error iz zero). As edges are deleted, the quadric error measure associated with the two end points of the edge are summed (this combines the plane equations) and an optimal collapse point can be computed. Edges connected to the collapse point are then reinserted into the queue after computing the new cost to delete them. The process continues until the desired reduction level is reached or topological constraints prevent further reduction. Note that this basic algorithm can be extended to higher dimensions by taking into account variation in attributes (i.e., scalars, vectors, and so on).

This paper is based on the work of Garland and Heckbert who first presented the quadric error measure at Siggraph '97 "Surface Simplification Using Quadric Error Metrics". For details of the algorithm Michael Garland's Ph.D. thesis is also recommended. Hughues Hoppe's Vis '99 paper, "New Quadric Metric for Simplifying Meshes with Appearance Attributes" is also a good take on the subject especially as it pertains to the error metric applied to attributes.

Thanks:: Thanks to Bradley Lowekamp of the National Library of Medicine/NIH for contributing this class.

Tests:: vtkQuadricDecimation (Tests)

Definition at line 70 of file vtkQuadricDecimation.h.

Member Typedef Documentation

typedef vtkPolyDataAlgorithm vtkQuadricDecimation::Superclass

Definition at line 73 of file vtkQuadricDecimation.h.

Constructor & Destructor Documentation

vtkQuadricDecimation::vtkQuadricDecimation ( )

protected

vtkQuadricDecimation::~vtkQuadricDecimation ( )

protected

Member Function Documentation

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

static

virtual int vtkQuadricDecimation::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 vtkPolyDataAlgorithm.

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

static

virtual vtkObjectBase* vtkQuadricDecimation::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkPolyDataAlgorithm.

vtkQuadricDecimation* vtkQuadricDecimation::NewInstance ( ) const

void vtkQuadricDecimation::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 vtkPolyDataAlgorithm.

static vtkQuadricDecimation* vtkQuadricDecimation::New ( )

static

virtual void vtkQuadricDecimation::SetTargetReduction ( double )

virtual

Set/Get the desired reduction (expressed as a fraction of the original number of triangles). The actual reduction may be less depending on triangulation and topological constraints.

virtual double vtkQuadricDecimation::GetTargetReduction ( )

virtual

Set/Get the desired reduction (expressed as a fraction of the original number of triangles). The actual reduction may be less depending on triangulation and topological constraints.

virtual void vtkQuadricDecimation::SetAttributeErrorMetric ( int )

virtual

Decide whether to include data attributes in the error metric. If off, then only geometric error is used to control the decimation. By default the attribute errors are off.

virtual int vtkQuadricDecimation::GetAttributeErrorMetric ( )

virtual

Decide whether to include data attributes in the error metric. If off, then only geometric error is used to control the decimation. By default the attribute errors are off.

virtual void vtkQuadricDecimation::AttributeErrorMetricOn ( )

virtual

Decide whether to include data attributes in the error metric. If off, then only geometric error is used to control the decimation. By default the attribute errors are off.

virtual void vtkQuadricDecimation::AttributeErrorMetricOff ( )

virtual

Decide whether to include data attributes in the error metric. If off, then only geometric error is used to control the decimation. By default the attribute errors are off.

virtual void vtkQuadricDecimation::SetScalarsAttribute ( int )

virtual