Use finite differences to estimate gradient. More...

#include <vtkFiniteDifferenceGradientEstimator.h>

Inheritance diagram for vtkFiniteDifferenceGradientEstimator:

Collaboration diagram for vtkFiniteDifferenceGradientEstimator:

Public Types
typedef vtkEncodedGradientEstimator	Superclass

Public Types inherited from vtkEncodedGradientEstimator
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...

vtkFiniteDifferenceGradientEstimator *	NewInstance () const

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


virtual void	SetSampleSpacingInVoxels (int)
	Set/Get the spacing between samples for the finite differences method used to compute the normal. More...

virtual int	GetSampleSpacingInVoxels ()
	Set/Get the spacing between samples for the finite differences method used to compute the normal. More...

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

vtkEncodedGradientEstimator *	NewInstance () const

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

void	Update (void)
	Recompute the encoded normals and gradient magnitudes. More...

unsigned short *	GetEncodedNormals (void)
	Get the encoded normals. More...

unsigned char *	GetGradientMagnitudes (void)
	Get the gradient magnitudes. More...

virtual int	GetUseCylinderClip ()

int *	GetCircleLimits ()

virtual int *	GetInputSize ()

virtual void	GetInputSize (int data[3])

virtual float *	GetInputAspect ()

virtual void	GetInputAspect (float data[3])

virtual void	SetInputData (vtkImageData *)
	Set/Get the scalar input for which the normals will be calculated. More...

virtual vtkImageData *	GetInputData ()
	Set/Get the scalar input for which the normals will be calculated. More...

virtual void	SetGradientMagnitudeScale (float)
	Set/Get the scale and bias for the gradient magnitude. More...

virtual float	GetGradientMagnitudeScale ()
	Set/Get the scale and bias for the gradient magnitude. More...

virtual void	SetGradientMagnitudeBias (float)
	Set/Get the scale and bias for the gradient magnitude. More...

virtual float	GetGradientMagnitudeBias ()
	Set/Get the scale and bias for the gradient magnitude. More...

virtual void	SetBoundsClip (vtkTypeBool)
	Turn on / off the bounding of the normal computation by the this->Bounds bounding box. More...

virtual vtkTypeBool	GetBoundsClip ()
	Turn on / off the bounding of the normal computation by the this->Bounds bounding box. More...

virtual void	BoundsClipOn ()
	Turn on / off the bounding of the normal computation by the this->Bounds bounding box. More...

virtual void	BoundsClipOff ()
	Turn on / off the bounding of the normal computation by the this->Bounds bounding box. More...

virtual void	SetBounds (int, int, int, int, int, int)
	Set / Get the bounds of the computation (used if this->ComputationBounds is 1.) The bounds are specified xmin, xmax, ymin, ymax, zmin, zmax. More...

virtual void	SetBounds (int[6])
	Set / Get the bounds of the computation (used if this->ComputationBounds is 1.) The bounds are specified xmin, xmax, ymin, ymax, zmin, zmax. More...

virtual int *	GetBounds ()
	Set / Get the bounds of the computation (used if this->ComputationBounds is 1.) The bounds are specified xmin, xmax, ymin, ymax, zmin, zmax. More...

virtual void	GetBounds (int data[6])
	Set / Get the bounds of the computation (used if this->ComputationBounds is 1.) The bounds are specified xmin, xmax, ymin, ymax, zmin, zmax. More...

int	GetEncodedNormalIndex (vtkIdType xyzIndex)
	Get the encoded normal at an x,y,z location in the volume. More...

int	GetEncodedNormalIndex (int xIndex, int yIndex, int zIndex)
	Get the encoded normal at an x,y,z location in the volume. More...

virtual void	SetNumberOfThreads (int)
	Get/Set the number of threads to create when encoding normals This defaults to the number of available processors on the machine. More...

virtual int	GetNumberOfThreads ()
	Get/Set the number of threads to create when encoding normals This defaults to the number of available processors on the machine. More...

void	SetDirectionEncoder (vtkDirectionEncoder *direnc)
	Set / Get the direction encoder used to encode normal directions to fit within two bytes. More...

virtual vtkDirectionEncoder *	GetDirectionEncoder ()
	Set / Get the direction encoder used to encode normal directions to fit within two bytes. More...

virtual void	SetComputeGradientMagnitudes (vtkTypeBool)
	If you don't want to compute gradient magnitudes (but you do want normals for shading) this can be used. More...

virtual vtkTypeBool	GetComputeGradientMagnitudes ()
	If you don't want to compute gradient magnitudes (but you do want normals for shading) this can be used. More...

virtual void	ComputeGradientMagnitudesOn ()
	If you don't want to compute gradient magnitudes (but you do want normals for shading) this can be used. More...

virtual void	ComputeGradientMagnitudesOff ()
	If you don't want to compute gradient magnitudes (but you do want normals for shading) this can be used. More...

virtual void	SetCylinderClip (vtkTypeBool)
	If the data in each slice is only contained within a circle circumscribed within the slice, and the slice is square, then don't compute anything outside the circle. More...

virtual vtkTypeBool	GetCylinderClip ()
	If the data in each slice is only contained within a circle circumscribed within the slice, and the slice is square, then don't compute anything outside the circle. More...

virtual void	CylinderClipOn ()
	If the data in each slice is only contained within a circle circumscribed within the slice, and the slice is square, then don't compute anything outside the circle. More...

virtual void	CylinderClipOff ()
	If the data in each slice is only contained within a circle circumscribed within the slice, and the slice is square, then don't compute anything outside the circle. More...

virtual float	GetLastUpdateTimeInSeconds ()
	Get the time required for the last update in seconds or cpu seconds. More...

virtual float	GetLastUpdateTimeInCPUSeconds ()
	Get the time required for the last update in seconds or cpu seconds. More...

void	SetZeroNormalThreshold (float v)
	Set / Get the ZeroNormalThreshold - this defines the minimum magnitude of a gradient that is considered sufficient to define a direction. More...

virtual float	GetZeroNormalThreshold ()
	Set / Get the ZeroNormalThreshold - this defines the minimum magnitude of a gradient that is considered sufficient to define a direction. More...

virtual void	SetZeroPad (vtkTypeBool)
	Assume that the data value outside the volume is zero when computing normals. More...

virtual vtkTypeBool	GetZeroPad ()
	Assume that the data value outside the volume is zero when computing normals. More...

virtual void	ZeroPadOn ()
	Assume that the data value outside the volume is zero when computing normals. More...

virtual void	ZeroPadOff ()
	Assume that the data value outside the volume is zero when computing normals. 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	PrintSelf (ostream &os, vtkIndent indent) override
	Methods invoked by print to print information about the object including superclasses. 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 vtkTypeBool	IsA (const char *name)
	Return 1 if this class is the same type of (or a subclass of) the named class. More...

virtual vtkIdType	GetNumberOfGenerationsFromBase (const char *name)
	Given the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). 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...

bool	GetIsInMemkind () const
	A local state flag that remembers whether this object lives in the normal or extended memory space. 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 vtkFiniteDifferenceGradientEstimator *	SafeDownCast (vtkObjectBase *o)

static vtkFiniteDifferenceGradientEstimator *	New ()
	Construct a vtkFiniteDifferenceGradientEstimator with a SampleSpacingInVoxels of 1. More...

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

static vtkEncodedGradientEstimator *	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 vtkIdType	GetNumberOfGenerationsFromBaseType (const char *name)
	Given a the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). More...

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

static void	SetMemkindDirectory (const char *directoryname)
	The name of a directory, ideally mounted -o dax, to memory map an extended memory space within. More...

static bool	GetUsingMemkind ()
	A global state flag that controls whether vtkObjects are constructed in the usual way (the default) or within the extended memory space. More...

Public Attributes
int	SampleSpacingInVoxels

Public Attributes inherited from vtkEncodedGradientEstimator
vtkImageData *	InputData

unsigned short *	EncodedNormals

int	EncodedNormalsSize [3]

unsigned char *	GradientMagnitudes

vtkTimeStamp	BuildTime

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkFiniteDifferenceGradientEstimator ()

	~vtkFiniteDifferenceGradientEstimator () override

void	UpdateNormals (void) override
	Recompute the encoded normals and gradient magnitudes. More...

Protected Member Functions inherited from vtkEncodedGradientEstimator
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkEncodedGradientEstimator ()

	~vtkEncodedGradientEstimator () override

void	ReportReferences (vtkGarbageCollector *) override

virtual void	UpdateNormals (void)=0

void	ComputeCircleLimits (int size)

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	RegisterInternal (vtkObjectBase *, vtkTypeBool check)

virtual void	UnRegisterInternal (vtkObjectBase *, vtkTypeBool check)

virtual void	ReportReferences (vtkGarbageCollector *)

	vtkObjectBase (const vtkObjectBase &)

void	operator= (const vtkObjectBase &)

Additional Inherited Members
Static Protected Member Functions inherited from vtkObjectBase
static vtkMallocingFunction	GetCurrentMallocFunction ()

static vtkReallocingFunction	GetCurrentReallocFunction ()

static vtkFreeingFunction	GetCurrentFreeFunction ()

static vtkFreeingFunction	GetAlternateFreeFunction ()

Protected Attributes inherited from vtkEncodedGradientEstimator
int	NumberOfThreads

vtkMultiThreader *	Threader

vtkDirectionEncoder *	DirectionEncoder

float	GradientMagnitudeScale

float	GradientMagnitudeBias

float	LastUpdateTimeInSeconds

float	LastUpdateTimeInCPUSeconds

float	ZeroNormalThreshold

vtkTypeBool	CylinderClip

int *	CircleLimits

int	CircleLimitsSize

int	UseCylinderClip

vtkTypeBool	BoundsClip

int	Bounds [6]

int	InputSize [3]

float	InputAspect [3]

vtkTypeBool	ComputeGradientMagnitudes

vtkTypeBool	ZeroPad

Protected Attributes inherited from vtkObject
bool	Debug

vtkTimeStamp	MTime

vtkSubjectHelper *	SubjectHelper

Protected Attributes inherited from vtkObjectBase
std::atomic< int32_t >	ReferenceCount

vtkWeakPointerBase **	WeakPointers

Detailed Description

Use finite differences to estimate gradient.

vtkFiniteDifferenceGradientEstimator is a concrete subclass of vtkEncodedGradientEstimator that uses a central differences technique to estimate the gradient. The gradient at some sample location (x,y,z) would be estimated by:

 nx = (f(x-dx,y,z) - f(x+dx,y,z)) / 2*dx;
 ny = (f(x,y-dy,z) - f(x,y+dy,z)) / 2*dy;
 nz = (f(x,y,z-dz) - f(x,y,z+dz)) / 2*dz;

This value is normalized to determine a unit direction vector and a magnitude. The normal is computed in voxel space, and dx = dy = dz = SampleSpacingInVoxels. A scaling factor is applied to convert this normal from voxel space to world coordinates.

See also: vtkEncodedGradientEstimator

Online Examples:

MinIntensityRendering

Definition at line 64 of file vtkFiniteDifferenceGradientEstimator.h.

Member Typedef Documentation

◆ Superclass

typedef vtkEncodedGradientEstimator vtkFiniteDifferenceGradientEstimator::Superclass

Definition at line 68 of file vtkFiniteDifferenceGradientEstimator.h.

Constructor & Destructor Documentation

◆ vtkFiniteDifferenceGradientEstimator()

vtkFiniteDifferenceGradientEstimator::vtkFiniteDifferenceGradientEstimator ( )

protected

◆ ~vtkFiniteDifferenceGradientEstimator()

vtkFiniteDifferenceGradientEstimator::~vtkFiniteDifferenceGradientEstimator ( )

overrideprotected

Member Function Documentation

◆ IsTypeOf()

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

static

◆ IsA()

virtual vtkTypeBool vtkFiniteDifferenceGradientEstimator::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 vtkEncodedGradientEstimator.

◆ SafeDownCast()

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

static

◆ NewInstanceInternal()

virtual vtkObjectBase * vtkFiniteDifferenceGradientEstimator::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkEncodedGradientEstimator.

◆ NewInstance()

vtkFiniteDifferenceGradientEstimator * vtkFiniteDifferenceGradientEstimator::NewInstance ( ) const

◆ PrintSelf()

void vtkFiniteDifferenceGradientEstimator::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 vtkEncodedGradientEstimator.

◆ New()

static vtkFiniteDifferenceGradientEstimator * vtkFiniteDifferenceGradientEstimator::New ( )

static

Construct a vtkFiniteDifferenceGradientEstimator with a SampleSpacingInVoxels of 1.

◆ SetSampleSpacingInVoxels()

virtual void vtkFiniteDifferenceGradientEstimator::SetSampleSpacingInVoxels ( int )

virtual

Set/Get the spacing between samples for the finite differences method used to compute the normal.

This spacing is in voxel units.

◆ GetSampleSpacingInVoxels()

virtual int vtkFiniteDifferenceGradientEstimator::GetSampleSpacingInVoxels ( )

virtual

Set/Get the spacing between samples for the finite differences method used to compute the normal.

This spacing is in voxel units.

◆ UpdateNormals()

void vtkFiniteDifferenceGradientEstimator::UpdateNormals ( void )

overrideprotectedvirtual

Recompute the encoded normals and gradient magnitudes.

Implements vtkEncodedGradientEstimator.

Member Data Documentation

◆ SampleSpacingInVoxels

int vtkFiniteDifferenceGradientEstimator::SampleSpacingInVoxels

Definition at line 87 of file vtkFiniteDifferenceGradientEstimator.h.

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

Rendering/Volume/vtkFiniteDifferenceGradientEstimator.h

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Superclass

Constructor & Destructor Documentation

◆ vtkFiniteDifferenceGradientEstimator()

◆ ~vtkFiniteDifferenceGradientEstimator()

Member Function Documentation

◆ IsTypeOf()

◆ IsA()

◆ SafeDownCast()

◆ NewInstanceInternal()

◆ NewInstance()

◆ PrintSelf()

◆ New()

◆ SetSampleSpacingInVoxels()

◆ GetSampleSpacingInVoxels()

◆ UpdateNormals()

Member Data Documentation

◆ SampleSpacingInVoxels