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vtkCurvatures Class Reference

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

#include <vtkCurvatures.h>

Inheritance diagram for vtkCurvatures:
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Collaboration diagram for vtkCurvatures:
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Public Types

typedef vtkPolyDataAlgorithm Superclass
 
- Public Types inherited from vtkPolyDataAlgorithm
typedef vtkAlgorithm Superclass
 
- Public Types inherited from vtkAlgorithm
typedef vtkObject Superclass
 
- Public Types inherited from vtkObject
typedef vtkObjectBase Superclass
 

Public Member Functions

virtual const char * GetClassName ()
 
virtual int IsA (const char *type)
 
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
vtkDataObjectGetInput ()
 
vtkDataObjectGetInput (int port)
 
vtkPolyDataGetPolyDataInput (int port)
 
vtkPolyDataGetOutput ()
 
vtkPolyDataGetOutput (int)
 
virtual void SetOutput (vtkDataObject *d)
 
virtual int ProcessRequest (vtkInformation *, vtkInformationVector **, vtkInformationVector *)
 
void SetInput (vtkDataObject *)
 
void SetInput (int, vtkDataObject *)
 
void AddInput (vtkDataObject *)
 
void AddInput (int, vtkDataObject *)
 
- Public Member Functions inherited from vtkAlgorithm
int HasExecutive ()
 
vtkExecutiveGetExecutive ()
 
virtual void SetExecutive (vtkExecutive *executive)
 
virtual int ModifyRequest (vtkInformation *request, int when)
 
vtkInformationGetInputPortInformation (int port)
 
vtkInformationGetOutputPortInformation (int port)
 
int GetNumberOfInputPorts ()
 
int GetNumberOfOutputPorts ()
 
void UpdateProgress (double amount)
 
vtkInformationGetInputArrayInformation (int idx)
 
void RemoveAllInputs ()
 
vtkDataObjectGetOutputDataObject (int port)
 
virtual void RemoveInputConnection (int port, vtkAlgorithmOutput *input)
 
int GetNumberOfInputConnections (int port)
 
int GetTotalNumberOfInputConnections ()
 
vtkAlgorithmOutputGetInputConnection (int port, int index)
 
virtual void Update ()
 
virtual void UpdateInformation ()
 
virtual void UpdateWholeExtent ()
 
void ConvertTotalInputToPortConnection (int ind, int &port, int &conn)
 
virtual double ComputePriority ()
 
int ProcessRequest (vtkInformation *request, vtkCollection *inInfo, vtkInformationVector *outInfo)
 
virtual int ComputePipelineMTime (vtkInformation *request, vtkInformationVector **inInfoVec, vtkInformationVector *outInfoVec, int requestFromOutputPort, unsigned long *mtime)
 
virtual vtkInformationGetInformation ()
 
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)
 
vtkDataObjectGetInputDataObject (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)
 
vtkAlgorithmOutputGetOutputPort (int index)
 
vtkAlgorithmOutputGetOutputPort ()
 
virtual void SetReleaseDataFlag (int)
 
virtual int GetReleaseDataFlag ()
 
void ReleaseDataFlagOn ()
 
void ReleaseDataFlagOff ()
 
int UpdateExtentIsEmpty (vtkDataObject *output)
 
int UpdateExtentIsEmpty (vtkInformation *pinfo, int extentType)
 
- Public Member Functions inherited from vtkObject
virtual void DebugOn ()
 
virtual void DebugOff ()
 
unsigned char GetDebug ()
 
void SetDebug (unsigned char 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)
 
vtkCommandGetCommand (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)
 
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 &os)
 
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 vtkCurvaturesSafeDownCast (vtkObject *o)
 
static vtkCurvaturesNew ()
 
- Static Public Member Functions inherited from vtkPolyDataAlgorithm
static vtkPolyDataAlgorithmNew ()
 
static int IsTypeOf (const char *type)
 
static vtkPolyDataAlgorithmSafeDownCast (vtkObject *o)
 
- Static Public Member Functions inherited from vtkAlgorithm
static vtkAlgorithmNew ()
 
static int IsTypeOf (const char *type)
 
static vtkAlgorithmSafeDownCast (vtkObject *o)
 
static void SetDefaultExecutivePrototype (vtkExecutive *proto)
 
static vtkInformationIntegerKeyINPUT_IS_OPTIONAL ()
 
static vtkInformationIntegerKeyINPUT_IS_REPEATABLE ()
 
static
vtkInformationInformationVectorKey
INPUT_REQUIRED_FIELDS ()
 
static
vtkInformationStringVectorKey
INPUT_REQUIRED_DATA_TYPE ()
 
static
vtkInformationInformationVectorKey
INPUT_ARRAYS_TO_PROCESS ()
 
static vtkInformationIntegerKeyINPUT_PORT ()
 
static vtkInformationIntegerKeyINPUT_CONNECTION ()
 
static vtkInformationIntegerKeyPRESERVES_DATASET ()
 
static vtkInformationIntegerKeyPRESERVES_GEOMETRY ()
 
static vtkInformationIntegerKeyPRESERVES_BOUNDS ()
 
static vtkInformationIntegerKeyPRESERVES_TOPOLOGY ()
 
static vtkInformationIntegerKeyPRESERVES_ATTRIBUTES ()
 
static vtkInformationIntegerKeyPRESERVES_RANGES ()
 
- Static Public Member Functions inherited from vtkObject
static int IsTypeOf (const char *type)
 
static vtkObjectSafeDownCast (vtkObject *o)
 
static vtkObjectNew ()
 
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 vtkObjectBaseNew ()
 

Protected Member Functions

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 *)
 
virtual void ExecuteData (vtkDataObject *output)
 
virtual void Execute ()
 
- 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 vtkExecutiveCreateDefaultExecutive ()
 
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)
 
vtkDataArrayGetInputArrayToProcess (int idx, vtkInformationVector **inputVector)
 
vtkDataArrayGetInputArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)
 
vtkDataArrayGetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)
 
vtkDataArrayGetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)
 
vtkDataArrayGetInputArrayToProcess (int idx, vtkDataObject *input)
 
vtkDataArrayGetInputArrayToProcess (int idx, vtkDataObject *input, int &association)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkDataObject *input)
 
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkDataObject *input, int &association)
 
vtkInformationGetInputArrayFieldInformation (int idx, vtkInformationVector **inputVector)
 
virtual void SetNthInputConnection (int port, int index, vtkAlgorithmOutput *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 &os)
 
 vtkObjectBase (const vtkObjectBase &)
 
void operator= (const vtkObjectBase &)
 

Protected Attributes

int CurvatureType
 
int InvertMeanCurvature
 
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 vtkInformationIntegerKeyPORT_REQUIREMENTS_FILLED ()
 
- Static Protected Attributes inherited from vtkAlgorithm
static vtkExecutiveDefaultExecutivePrototype
 
- Friends inherited from vtkObject

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 75 of file vtkCurvatures.h.

Member Typedef Documentation

Definition at line 78 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

virtual const char* vtkCurvatures::GetClassName ( )
virtual

Reimplemented from vtkPolyDataAlgorithm.

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 ( vtkObject o)
static
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

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

virtual int vtkCurvatures::GetCurvatureType ( )
virtual

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

void vtkCurvatures::SetCurvatureTypeToGaussian ( )
inline

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

Definition at line 90 of file vtkCurvatures.h.

void vtkCurvatures::SetCurvatureTypeToMean ( )
inline

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

Definition at line 92 of file vtkCurvatures.h.

void vtkCurvatures::SetCurvatureTypeToMaximum ( )
inline

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

Definition at line 94 of file vtkCurvatures.h.

void vtkCurvatures::SetCurvatureTypeToMinimum ( )
inline

Set/Get Curvature type VTK_CURVATURE_GAUSS: Gaussian curvature, stored as DataArray "Gauss_Curvature" VTK_CURVATURE_MEAN : Mean curvature, stored as DataArray "Mean_Curvature"

Definition at line 96 of file vtkCurvatures.h.

virtual void vtkCurvatures::SetInvertMeanCurvature ( int  )
virtual

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

virtual int vtkCurvatures::GetInvertMeanCurvature ( )
virtual

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

virtual void vtkCurvatures::InvertMeanCurvatureOn ( )
virtual

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

virtual void vtkCurvatures::InvertMeanCurvatureOff ( )
virtual

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

int vtkCurvatures::RequestData ( vtkInformation request,
vtkInformationVector **  inputVector,
vtkInformationVector outputVector 
)
protectedvirtual

This is called by the superclass. This is the method you should override.

Reimplemented from vtkPolyDataAlgorithm.

void vtkCurvatures::GetGaussCurvature ( vtkPolyData output)
protected

discrete Gauss curvature (K) computation, cf http://www-ipg.umds.ac.uk/p.batchelor/curvatures/curvatures.html

void vtkCurvatures::GetMeanCurvature ( vtkPolyData output)
protected
void vtkCurvatures::GetMaximumCurvature ( vtkPolyData input,
vtkPolyData output 
)
protected

Maximum principal curvature $k_max = H + sqrt(H^2 -K)$

void vtkCurvatures::GetMinimumCurvature ( vtkPolyData input,
vtkPolyData output 
)
protected

Minimum principal curvature $k_min = H - sqrt(H^2 -K)$

Member Data Documentation

int vtkCurvatures::CurvatureType
protected

Definition at line 129 of file vtkCurvatures.h.

int vtkCurvatures::InvertMeanCurvature
protected

Definition at line 130 of file vtkCurvatures.h.


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