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vtkPiecewiseFunction Class Reference

Defines a 1D piecewise function. More...

#include <vtkPiecewiseFunction.h>

Inheritance diagram for vtkPiecewiseFunction:

[legend]Collaboration diagram for vtkPiecewiseFunction:

[legend]List of all members.

Public Methods
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
vtkDataObject *	MakeObject ()
void	Initialize ()
void	DeepCopy (vtkDataObject *f)
void	ShallowCopy (vtkDataObject *f)
int	GetDataObjectType ()
int	GetSize ()
void	RemoveAllPoints ()
void	AddSegment (float x1, float val1, float x2, float val2)
float	GetValue (float x)
float *	GetDataPointer ()
float *	GetRange ()
void	GetTable (float x1, float x2, int size, float *table, int stride=1)
const char *	GetType ()
unsigned long	GetMTime ()
float	GetFirstNonZeroValue ()
void	AddPoint (float x, float val)
void	RemovePoint (float x)
void	BuildFunctionFromTable (float x1, float x2, int size, float *table, int stride=1)
virtual void	SetClamping (int)
virtual int	GetClamping ()
virtual void	ClampingOn ()
virtual void	ClampingOff ()
Static Public Methods
vtkPiecewiseFunction *	New ()
int	IsTypeOf (const char *type)
vtkPiecewiseFunction *	SafeDownCast (vtkObject *o)
Protected Methods
	vtkPiecewiseFunction ()
	~vtkPiecewiseFunction ()
void	IncreaseArraySize ()
int	InsertPoint (float x, float val)
void	MovePoints (int index, int down)
Protected Attributes
int	ArraySize
int	Clamping
float *	Function
int	FunctionSize
float	FunctionRange [2]

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Detailed Description

Defines a 1D piecewise function.

Date:

2001/11/13 14:12:57

Revision:

1.28

Defines a piecewise linear function mapping. Used for transfer functions in volume rendering.

Examples:

vtkPiecewiseFunction (Examples)

Tests:

vtkPiecewiseFunction (Tests)

Definition at line 63 of file vtkPiecewiseFunction.h.

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Constructor & Destructor Documentation

vtkPiecewiseFunction::vtkPiecewiseFunction (    )  [protected]

vtkPiecewiseFunction::~vtkPiecewiseFunction (    )  [protected]

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Member Function Documentation

vtkPiecewiseFunction* vtkPiecewiseFunction::New (    )  [static]

Create an object with Debug turned off, modified time initialized to zero, and reference counting on. Reimplemented from vtkDataObject.

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

Return the class name as a string. This method is defined in all subclasses of vtkObject with the vtkTypeMacro found in vtkSetGet.h. Reimplemented from vtkDataObject.

int vtkPiecewiseFunction::IsTypeOf (  const char *    type )  [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 vtkTypeMacro found in vtkSetGet.h. Reimplemented from vtkDataObject.

virtual int vtkPiecewiseFunction::IsA (  const char *    type )  [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 vtkDataObject.

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

Will cast the supplied object to vtkObject* is this is a safe operation (i.e., a safe downcast); otherwise NULL is returned. This method is defined in all subclasses of vtkObject with the vtkTypeMacro found in vtkSetGet.h. Reimplemented from vtkDataObject.

void vtkPiecewiseFunction::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 vtkDataObject.

vtkDataObject* vtkPiecewiseFunction::MakeObject (    )  [virtual]

Create concrete instance of this data object. Reimplemented from vtkDataObject.

void vtkPiecewiseFunction::Initialize (    )  [virtual]

Reimplemented from vtkDataObject.

void vtkPiecewiseFunction::DeepCopy (  vtkDataObject *    f )  [virtual]

Shallow and Deep copy. These copy the data, but not any of the pipeline connections. Reimplemented from vtkDataObject.

void vtkPiecewiseFunction::ShallowCopy (  vtkDataObject *    f )  [virtual]

Shallow and Deep copy. These copy the data, but not any of the pipeline connections. Reimplemented from vtkDataObject.

int vtkPiecewiseFunction::GetDataObjectType (    )  [inline, virtual]

Return what type of dataset this is. Reimplemented from vtkDataObject. Definition at line 76 of file vtkPiecewiseFunction.h.

int vtkPiecewiseFunction::GetSize (    )

Get the number of points used to specify the function

void vtkPiecewiseFunction::AddPoint (  float    x, float    val )

Add/Remove points to/from the function. If a duplicate point is added then the function value is changed at that location.

void vtkPiecewiseFunction::RemovePoint (  float    x )

Add/Remove points to/from the function. If a duplicate point is added then the function value is changed at that location.

void vtkPiecewiseFunction::RemoveAllPoints (    )

Removes all points from the function.

void vtkPiecewiseFunction::AddSegment (  float    x1, float    val1, float    x2, float    val2 )

Add a line segment to the function. All points defined between the two points specified are removed from the function.

float vtkPiecewiseFunction::GetValue (  float    x )

Returns the value of the function at the specified location using the specified interpolation. Returns zero if the specified location is outside the min and max points of the function.

float* vtkPiecewiseFunction::GetDataPointer (    )  [inline]

Returns a pointer to the data stored in the table. Definition at line 101 of file vtkPiecewiseFunction.h.

float* vtkPiecewiseFunction::GetRange (    )

Returns the min and max point locations of the function.

void vtkPiecewiseFunction::GetTable (  float    x1, float    x2, int    size, float *    table, int    stride = 1 )

Fills in an array of function values evaluated at regular intervals. Parameter "stride" is used to step through the output "table". It is used by vtkColorTransferFunction to fill in an rgb table using three separate piecewise functions and three separate calls to GetTable().

void vtkPiecewiseFunction::BuildFunctionFromTable (  float    x1, float    x2, int    size, float *    table, int    stride = 1 )

Constructs a piecewise function from a table. Function range is is set to [x1, x2], function size is set to size, and function points are regularly spaced between x1 and x2. Parameter "stride" is is step through the input table. It is used by vtkColorTransferFunction to construct 3 piecewise functions from an rgb table.

virtual void vtkPiecewiseFunction::SetClamping (  int    )  [virtual]

When zero range clamping is Off, GetValue() returns 0.0 when a value is requested outside of the points specified. When zero range clamping is On, GetValue() returns the value at the value at the lowest point for a request below all points specified and returns the value at the highest point for a request above all points specified. On is the default.

virtual int vtkPiecewiseFunction::GetClamping (    )  [virtual]

When zero range clamping is Off, GetValue() returns 0.0 when a value is requested outside of the points specified. When zero range clamping is On, GetValue() returns the value at the value at the lowest point for a request below all points specified and returns the value at the highest point for a request above all points specified. On is the default.

virtual void vtkPiecewiseFunction::ClampingOn (    )  [virtual]

When zero range clamping is Off, GetValue() returns 0.0 when a value is requested outside of the points specified. When zero range clamping is On, GetValue() returns the value at the value at the lowest point for a request below all points specified and returns the value at the highest point for a request above all points specified. On is the default.

virtual void vtkPiecewiseFunction::ClampingOff (    )  [virtual]

When zero range clamping is Off, GetValue() returns 0.0 when a value is requested outside of the points specified. When zero range clamping is On, GetValue() returns the value at the value at the lowest point for a request below all points specified and returns the value at the highest point for a request above all points specified. On is the default.

const char* vtkPiecewiseFunction::GetType (    )

Return the type of function: Function Types: 0 : Constant (No change in slope between end points) 1 : NonDecreasing (Always increasing or zero slope) 2 : NonIncreasing (Always decreasing or zero slope) 3 : Varied (Contains both decreasing and increasing slopes)

unsigned long vtkPiecewiseFunction::GetMTime (    )  [virtual]

Get the mtime of this object - override to consider the mtime of the source as well. Reimplemented from vtkDataObject.

float vtkPiecewiseFunction::GetFirstNonZeroValue (    )

Returns the first point location which precedes a non-zero segment of the function. Note that the value at this point may be zero.

void vtkPiecewiseFunction::IncreaseArraySize (    )  [protected]

int vtkPiecewiseFunction::InsertPoint (  float    x, float    val )  [protected]

void vtkPiecewiseFunction::MovePoints (  int    index, int    down )  [protected]

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Member Data Documentation

int vtkPiecewiseFunction::ArraySize [protected]

Definition at line 154 of file vtkPiecewiseFunction.h.

int vtkPiecewiseFunction::Clamping [protected]

Definition at line 160 of file vtkPiecewiseFunction.h.

float* vtkPiecewiseFunction::Function [protected]

Definition at line 163 of file vtkPiecewiseFunction.h.

int vtkPiecewiseFunction::FunctionSize [protected]

Definition at line 166 of file vtkPiecewiseFunction.h.

float vtkPiecewiseFunction::FunctionRange[2] [protected]

Definition at line 169 of file vtkPiecewiseFunction.h.

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

• Filtering/vtkPiecewiseFunction.h

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