compute curvatures (Gauss and mean) of a Polydata object More...

#include <vtkCurvatures.h>

Inheritance diagram for vtkCurvatures:

Collaboration diagram for vtkCurvatures:

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)

vtkCurvatures *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent)


virtual void	SetCurvatureType (int)

virtual int	GetCurvatureType ()

void	SetCurvatureTypeToGaussian ()

void	SetCurvatureTypeToMean ()

void	SetCurvatureTypeToMaximum ()

void	SetCurvatureTypeToMinimum ()

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 vtkCurvatures *	SafeDownCast (vtkObjectBase *o)

static vtkCurvatures *	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

int	RequestData (vtkInformation , vtkInformationVector , vtkInformationVector )

void	GetGaussCurvature (vtkPolyData *output)

void	GetMeanCurvature (vtkPolyData *output)

void	GetMaximumCurvature (vtkPolyData input, vtkPolyData output)

void	GetMinimumCurvature (vtkPolyData input, vtkPolyData output)

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
int	CurvatureType

int	InvertMeanCurvature

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

virtual void	SetInvertMeanCurvature (int)

virtual int	GetInvertMeanCurvature ()

virtual void	InvertMeanCurvatureOn ()

virtual void	InvertMeanCurvatureOff ()

	vtkCurvatures ()

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

compute curvatures (Gauss and mean) of a Polydata object

vtkCurvatures takes a polydata input and computes the curvature of the mesh at each point. Four possible methods of computation are available :

Gauss Curvature discrete Gauss curvature (K) computation, $K(vertex v) = 2*PI-\sum_{facet neighbs f of v} (angle_f at v)$ The contribution of every facet is for the moment weighted by $Area(facet)/3$ The units of Gaussian Curvature are $[1/m^2]$

Mean Curvature $H(vertex v) = average over edges neighbs e of H(e)$ $H(edge e) = length(e)*dihedral_angle(e)$ NB: dihedral_angle is the ORIENTED angle between -PI and PI, this means that the surface is assumed to be orientable the computation creates the orientation The units of Mean Curvature are [1/m]

Maximum ( $k_max$ ) and Minimum ( $k_min$ ) Principal Curvatures $k_max = H + sqrt(H^2 - K)$ $k_min = H - sqrt(H^2 - K)$ Excepting spherical and planar surfaces which have equal principal curvatures, the curvature at a point on a surface varies with the direction one "sets off" from the point. For all directions, the curvature will pass through two extrema: a minimum ( $k_min$ ) and a maximum ( $k_max$ ) which occur at mutually orthogonal directions to each other.

NB. The sign of the Gauss curvature is a geometric ivariant, it should be +ve when the surface looks like a sphere, -ve when it looks like a saddle, however, the sign of the Mean curvature is not, it depends on the convention for normals - This code assumes that normals point outwards (ie from the surface of a sphere outwards). If a given mesh produces curvatures of opposite senses then the flag InvertMeanCurvature can be set and the Curvature reported by the Mean calculation will be inverted.

Thanks:: Philip Batchelor phili.nosp@m.pp.b.nosp@m.atche.nosp@m.lor@.nosp@m.kcl.a.nosp@m.c.uk for creating and contributing the class and Andrew Maclean a.mac.nosp@m.lean.nosp@m.@acfr.nosp@m..usy.nosp@m.d.edu.nosp@m..au for cleanups and fixes. Thanks also to Goodwin Lawlor for contributing patch to calculate principal curvatures

Tests:: vtkCurvatures (Tests)

Definition at line 76 of file vtkCurvatures.h.

Member Typedef Documentation

typedef vtkPolyDataAlgorithm vtkCurvatures::Superclass

Definition at line 79 of file vtkCurvatures.h.

Constructor & Destructor Documentation

vtkCurvatures::vtkCurvatures ( )

protected

Set/Get the flag which inverts the mean curvature calculation for meshes with inward pointing normals (default false)

Member Function Documentation

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

static

virtual int vtkCurvatures::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 vtkCurvatures* vtkCurvatures::SafeDownCast ( vtkObjectBase * o )

static

virtual vtkObjectBase* vtkCurvatures::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkPolyDataAlgorithm.

vtkCurvatures* vtkCurvatures::NewInstance ( ) const

void vtkCurvatures::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 vtkCurvatures* vtkCurvatures::New ( )

static

Construct with curvature type set to Gauss

virtual void vtkCurvatures::SetCurvatureType ( int )

virtual