vtkGaussianSplatter Class Reference

#include <vtkGaussianSplatter.h>

Inheritance diagram for vtkGaussianSplatter:

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Collaboration diagram for vtkGaussianSplatter:

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List of all members.

Detailed Description

splat points into a volume with an elliptical, Gaussian distribution

vtkGaussianSplatter is a filter that injects input points into a structured points (volume) dataset. As each point is injected, it "splats" or distributes values to nearby voxels. Data is distributed using an elliptical, Gaussian distribution function. The distribution function is modified using scalar values (expands distribution) or normals (creates ellipsoidal distribution rather than spherical).

In general, the Gaussian distribution function f(x) around a given splat point p is given by

f(x) = ScaleFactor * exp( ExponentFactor*((r/Radius)**2) )

where x is the current voxel sample point; r is the distance |x-p| ExponentFactor <= 0.0, and ScaleFactor can be multiplied by the scalar value of the point p that is currently being splatted.

If points normals are present (and NormalWarping is on), then the splat function becomes elliptical (as compared to the spherical one described by the previous equation). The Gaussian distribution function then becomes:

f(x) = ScaleFactor * exp( ExponentFactor*( ((rxy/E)**2 + z**2)/R**2) )

where E is a user-defined eccentricity factor that controls the elliptical shape of the splat; z is the distance of the current voxel sample point along normal N; and rxy is the distance of x in the direction prependicular to N.

This class is typically used to convert point-valued distributions into a volume representation. The volume is then usually iso-surfaced or volume rendered to generate a visualization. It can be used to create surfaces from point distributions, or to create structure (i.e., topology) when none exists.

Warning:: The input to this filter is any dataset type. This filter can be used to resample any form of data, i.e., the input data need not be unstructured.
Some voxels may never receive a contribution during the splatting process. The final value of these points can be specified with the "NullValue" instance variable.

See also:: vtkShepardMethod

Examples:: vtkGaussianSplatter (Examples)

Tests:: vtkGaussianSplatter (Tests)

Definition at line 84 of file vtkGaussianSplatter.h.


Public Types
typedef vtkImageAlgorithm	Superclass
Public Member Functions
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)

void	SetSampleDimensions (int i, int j, int k)
void	SetSampleDimensions (int dim[3])
virtual int *	GetSampleDimensions ()
virtual void	GetSampleDimensions (int data[3])

virtual void	SetModelBounds (double, double, double, double, double, double)
virtual void	SetModelBounds (double[6])
virtual double *	GetModelBounds ()
virtual void	GetModelBounds (double data[6])

virtual void	SetRadius (double)
virtual double	GetRadius ()

virtual void	SetScaleFactor (double)
virtual double	GetScaleFactor ()

virtual void	SetExponentFactor (double)
virtual double	GetExponentFactor ()

virtual void	SetNormalWarping (int)
virtual int	GetNormalWarping ()
virtual void	NormalWarpingOn ()
virtual void	NormalWarpingOff ()

virtual void	SetEccentricity (double)
virtual double	GetEccentricity ()

virtual void	SetScalarWarping (int)
virtual int	GetScalarWarping ()
virtual void	ScalarWarpingOn ()
virtual void	ScalarWarpingOff ()

virtual void	SetCapping (int)
virtual int	GetCapping ()
virtual void	CappingOn ()
virtual void	CappingOff ()

virtual void	SetCapValue (double)
virtual double	GetCapValue ()

virtual void	SetAccumulationMode (int)
virtual int	GetAccumulationMode ()
void	SetAccumulationModeToMin ()
void	SetAccumulationModeToMax ()
void	SetAccumulationModeToSum ()
const char *	GetAccumulationModeAsString ()

virtual void	SetNullValue (double)
virtual double	GetNullValue ()

void	ComputeModelBounds (vtkDataSet input, vtkImageData output, vtkInformation *outInfo)
Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkGaussianSplatter *	SafeDownCast (vtkObject *o)
static vtkGaussianSplatter *	New ()
Protected Member Functions
	vtkGaussianSplatter ()
	~vtkGaussianSplatter ()
virtual int	FillInputPortInformation (int port, vtkInformation *info)
virtual int	RequestInformation (vtkInformation , vtkInformationVector , vtkInformationVector )
virtual int	RequestData (vtkInformation , vtkInformationVector , vtkInformationVector )
void	Cap (vtkDoubleArray *s)
double	Gaussian (double x[3])
double	EccentricGaussian (double x[3])
double	ScalarSampling (double s)
double	PositionSampling (double)
void	SetScalar (int idx, double dist2, vtkDoubleArray *newScalars)
Protected Attributes
int	SampleDimensions [3]
double	Radius
double	ExponentFactor
double	ModelBounds [6]
int	NormalWarping
double	Eccentricity
int	ScalarWarping
double	ScaleFactor
int	Capping
double	CapValue
int	AccumulationMode

Member Typedef Documentation

typedef vtkImageAlgorithm vtkGaussianSplatter::Superclass

Reimplemented from vtkImageAlgorithm.

Definition at line 87 of file vtkGaussianSplatter.h.

Constructor & Destructor Documentation

vtkGaussianSplatter::vtkGaussianSplatter ( ) [protected]

vtkGaussianSplatter::~vtkGaussianSplatter ( ) [inline, protected]

Definition at line 211 of file vtkGaussianSplatter.h.

Member Function Documentation

virtual const char* vtkGaussianSplatter::GetClassName ( ) [virtual]

Reimplemented from vtkImageAlgorithm.

static int vtkGaussianSplatter::IsTypeOf ( const char * name ) [static]

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkImageAlgorithm.

virtual int vtkGaussianSplatter::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 vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkImageAlgorithm.

static vtkGaussianSplatter* vtkGaussianSplatter::SafeDownCast ( vtkObject * o ) [static]

Reimplemented from vtkImageAlgorithm.

void vtkGaussianSplatter::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 vtkImageAlgorithm.

static vtkGaussianSplatter* vtkGaussianSplatter::New ( ) [static]

Construct object with dimensions=(50,50,50); automatic computation of bounds; a splat radius of 0.1; an exponent factor of -5; and normal and scalar warping turned on.

Reimplemented from vtkAlgorithm.

void vtkGaussianSplatter::SetSampleDimensions	(	int	i,
		int	j,
		int	k
	)

Set / get the dimensions of the sampling structured point set. Higher values produce better results but are much slower.

void vtkGaussianSplatter::SetSampleDimensions ( int dim[3] )

Set / get the dimensions of the sampling structured point set. Higher values produce better results but are much slower.

virtual int* vtkGaussianSplatter::GetSampleDimensions ( ) [virtual]

Set / get the dimensions of the sampling structured point set. Higher values produce better results but are much slower.

virtual void vtkGaussianSplatter::GetSampleDimensions ( int data[3] ) [virtual]

Set / get the dimensions of the sampling structured point set. Higher values produce better results but are much slower.

virtual void vtkGaussianSplatter::SetModelBounds	(	double	,
		double	,
		double	,
		double	,
		double	,
		double
	)			`[virtual]`

Set / get the (xmin,xmax, ymin,ymax, zmin,zmax) bounding box in which the sampling is performed. If any of the (min,max) bounds values are min >= max, then the bounds will be computed automatically from the input data. Otherwise, the user-specified bounds will be used.

virtual void vtkGaussianSplatter::SetModelBounds ( double [6] ) [virtual]

Set / get the (xmin,xmax, ymin,ymax, zmin,zmax) bounding box in which the sampling is performed. If any of the (min,max) bounds values are min >= max, then the bounds will be computed automatically from the input data. Otherwise, the user-specified bounds will be used.

virtual double* vtkGaussianSplatter::GetModelBounds ( ) [virtual]

Set / get the (xmin,xmax, ymin,ymax, zmin,zmax) bounding box in which the sampling is performed. If any of the (min,max) bounds values are min >= max, then the bounds will be computed automatically from the input data. Otherwise, the user-specified bounds will be used.

virtual void vtkGaussianSplatter::GetModelBounds ( double data[6] ) [virtual]

Set / get the (xmin,xmax, ymin,ymax, zmin,zmax) bounding box in which the sampling is performed. If any of the (min,max) bounds values are min >= max, then the bounds will be computed automatically from the input data. Otherwise, the user-specified bounds will be used.

virtual void vtkGaussianSplatter::SetRadius ( double ) [virtual]

Set / get the radius of propagation of the splat. This value is expressed as a percentage of the length of the longest side of the sampling volume. Smaller numbers greatly reduce execution time.

virtual double vtkGaussianSplatter::GetRadius ( ) [virtual]

Set / get the radius of propagation of the splat. This value is expressed as a percentage of the length of the longest side of the sampling volume. Smaller numbers greatly reduce execution time.

virtual void vtkGaussianSplatter::SetScaleFactor ( double ) [virtual]

Multiply Gaussian splat distribution by this value. If ScalarWarping is on, then the Scalar value will be multiplied by the ScaleFactor times the Gaussian function.

virtual double vtkGaussianSplatter::GetScaleFactor ( ) [virtual]

Multiply Gaussian splat distribution by this value. If ScalarWarping is on, then the Scalar value will be multiplied by the ScaleFactor times the Gaussian function.

virtual void vtkGaussianSplatter::SetExponentFactor ( double ) [virtual]

Set / get the sharpness of decay of the splats. This is the exponent constant in the Gaussian equation. Normally this is a negative value.

virtual double vtkGaussianSplatter::GetExponentFactor ( ) [virtual]

Set / get the sharpness of decay of the splats. This is the exponent constant in the Gaussian equation. Normally this is a negative value.

virtual void vtkGaussianSplatter::SetNormalWarping ( int ) [virtual]

Turn on/off the generation of elliptical splats. If normal warping is on, then the input normals affect the distribution of the splat. This boolean is used in combination with the Eccentricity ivar.

virtual int vtkGaussianSplatter::GetNormalWarping ( ) [virtual]

Turn on/off the generation of elliptical splats. If normal warping is on, then the input normals affect the distribution of the splat. This boolean is used in combination with the Eccentricity ivar.

virtual void vtkGaussianSplatter::NormalWarpingOn ( ) [virtual]

Turn on/off the generation of elliptical splats. If normal warping is on, then the input normals affect the distribution of the splat. This boolean is used in combination with the Eccentricity ivar.

virtual void vtkGaussianSplatter::NormalWarpingOff ( ) [virtual]

Turn on/off the generation of elliptical splats. If normal warping is on, then the input normals affect the distribution of the splat. This boolean is used in combination with the Eccentricity ivar.

virtual void vtkGaussianSplatter::SetEccentricity ( double ) [virtual]

Control the shape of elliptical splatting. Eccentricity is the ratio of the major axis (aligned along normal) to the minor (axes) aligned along other two axes. So Eccentricity > 1 creates needles with the long axis in the direction of the normal; Eccentricity<1 creates pancakes perpendicular to the normal vector.

virtual double vtkGaussianSplatter::GetEccentricity ( ) [virtual]

Control the shape of elliptical splatting. Eccentricity is the ratio of the major axis (aligned along normal) to the minor (axes) aligned along other two axes. So Eccentricity > 1 creates needles with the long axis in the direction of the normal; Eccentricity<1 creates pancakes perpendicular to the normal vector.

virtual void vtkGaussianSplatter::SetScalarWarping ( int ) [virtual]

Turn on/off the scaling of splats by scalar value.

virtual int vtkGaussianSplatter::GetScalarWarping ( ) [virtual]

Turn on/off the scaling of splats by scalar value.

virtual void vtkGaussianSplatter::ScalarWarpingOn ( ) [virtual]

Turn on/off the scaling of splats by scalar value.

virtual void vtkGaussianSplatter::ScalarWarpingOff ( ) [virtual]

Turn on/off the scaling of splats by scalar value.

virtual void vtkGaussianSplatter::SetCapping ( int ) [virtual]

Turn on/off the capping of the outer boundary of the volume to a specified cap value. This can be used to close surfaces (after iso-surfacing) and create other effects.

virtual int vtkGaussianSplatter::GetCapping ( ) [virtual]

Turn on/off the capping of the outer boundary of the volume to a specified cap value. This can be used to close surfaces (after iso-surfacing) and create other effects.

virtual void vtkGaussianSplatter::CappingOn ( ) [virtual]

Turn on/off the capping of the outer boundary of the volume to a specified cap value. This can be used to close surfaces (after iso-surfacing) and create other effects.

virtual void vtkGaussianSplatter::CappingOff ( ) [virtual]

Turn on/off the capping of the outer boundary of the volume to a specified cap value. This can be used to close surfaces (after iso-surfacing) and create other effects.

virtual void vtkGaussianSplatter::SetCapValue ( double ) [virtual]

Specify the cap value to use. (This instance variable only has effect if the ivar Capping is on.)

virtual double vtkGaussianSplatter::GetCapValue ( ) [virtual]

Specify the cap value to use. (This instance variable only has effect if the ivar Capping is on.)

virtual void vtkGaussianSplatter::SetAccumulationMode ( int ) [virtual]