vtkTableBasedClipDataSet Class Reference

#include <vtkTableBasedClipDataSet.h>

Inheritance diagram for vtkTableBasedClipDataSet:

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Collaboration diagram for vtkTableBasedClipDataSet:

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List of all members.

Detailed Description

Clip any dataset with a user-specified implicit function or an input scalar point data array.

vtkTableBasedClipDataSet is a filter that clips any type of dataset using either any subclass of vtkImplicitFunction or an input scalar point data array. Clipping means that it actually "cuts" through the cells of the dataset, returning everything outside the specified implicit function (or greater than the scalar value) including "pieces" of a cell (Note to compare this with vtkExtractGeometry, which pulls out entire, uncut cells). The output of this filter is a vtkUnstructuredGrid data.

To use this filter, you need to decide whether an implicit function or an input scalar point data array is used for clipping. For the former case, 1) define an implicit function 2) provide it to this filter via SetClipFunction() If a clipping function is not specified, or GenerateClipScalars is off( the default), the input scalar point data array is then employed for clipping.

You can also specify a scalar (iso-)value, which is used to decide what is inside and outside the implicit function. You can also reverse the sense of what inside/outside is by setting IVAR InsideOut. The clipping algorithm proceeds by computing an implicit function value or using the input scalar point data value for each point in the dataset. This is compared against the scalar (iso-)value to determine the inside/outside status.

Although this filter sometimes (but rarely) may resort to the sibling class vtkClipDataSet for handling some special grids (such as cylinders or cones with capping faces in the form of a vtkPolyData), it itself is able to deal with most grids. It is worth mentioning that vtkTableBasedClipDataSet is capable of addressing the artifacts that may occur with vtkClipDataSet due to the possibly inconsistent triangulation modes between neighboring cells. In addition, the former is much faster than the latter. Furthermore, the former produces less cells (with ratio usually being 5~6) than by the latter in the output. In other words, this filter retains the original cells (i.e., without triangulation / tetrahedralization) wherever possible. All these advantages are gained by adopting the unique clipping and triangulation tables proposed by VisIt.

Warning:: vtkTableBasedClipDataSet makes use of a hash table (that is provided by class maintained by internal class vtkTableBasedClipperDataSetFromVolume) to achieve rapid removal of duplicate points. The hash-based mechanism simply compares the point Ids, without considering the actual inter-point distance (vtkClipDataSet adopts vtkMergePoints that though considers the inter-point distance for robust points merging ). As a result, some duplicate points may be present in the output. This problem occurs when some boundary (cut-through cells) happen to have faces EXACTLY aligned with the clipping plane (such as Plane, Box, or other implicit functions with planar shapes). The occurrence (though very rare) of duplicate points produces degenerate cells, which can be fixed by post-processing the output with a filter like vtkCleanGrid.

Thanks:: This filter was adapted from the VisIt clipper (vtkVisItClipper).

See also:: vtkClipDataSet vtkClipVolume vtkClipPolyData vtkCutter vtkImplicitFunction

Definition at line 101 of file vtkTableBasedClipDataSet.h.


virtual int	ProcessRequest (vtkInformation , vtkInformationVector , vtkInformationVector )
	vtkTableBasedClipDataSet (vtkImplicitFunction *cf=NULL)
	~vtkTableBasedClipDataSet ()
Public Types
typedef vtkUnstructuredGridAlgorithm	Superclass
Public Member Functions
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
void	PrintSelf (ostream &os, vtkIndent indent)
unsigned long	GetMTime ()
void	CreateDefaultLocator ()
vtkUnstructuredGrid *	GetClippedOutput ()

virtual void	SetInsideOut (int)
virtual int	GetInsideOut ()
virtual void	InsideOutOn ()
virtual void	InsideOutOff ()

virtual void	SetValue (double)
virtual double	GetValue ()

virtual void	SetUseValueAsOffset (bool)
virtual bool	GetUseValueAsOffset ()
virtual void	UseValueAsOffsetOn ()
virtual void	UseValueAsOffsetOff ()

virtual void	SetClipFunction (vtkImplicitFunction *)
virtual vtkImplicitFunction *	GetClipFunction ()

virtual void	SetGenerateClipScalars (int)
virtual int	GetGenerateClipScalars ()
virtual void	GenerateClipScalarsOn ()
virtual void	GenerateClipScalarsOff ()

void	SetLocator (vtkIncrementalPointLocator *locator)
virtual vtkIncrementalPointLocator *	GetLocator ()

virtual void	SetMergeTolerance (double)
virtual double	GetMergeTolerance ()

virtual void	SetGenerateClippedOutput (int)
virtual int	GetGenerateClippedOutput ()
virtual void	GenerateClippedOutputOn ()
virtual void	GenerateClippedOutputOff ()
Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkTableBasedClipDataSet *	SafeDownCast (vtkObject *o)
static vtkTableBasedClipDataSet *	New ()
Protected Member Functions
virtual int	RequestData (vtkInformation , vtkInformationVector , vtkInformationVector )
virtual int	FillInputPortInformation (int port, vtkInformation *info)
void	InternalProgressCallback (vtkAlgorithm *algorithm)

void	ClipDataSet (vtkDataSet pDataSet, vtkDataArray clipAray, vtkUnstructuredGrid *unstruct)

void	ClipImageData (vtkDataSet inputGrd, vtkDataArray clipAray, double isoValue, vtkUnstructuredGrid *outputUG)

void	ClipPolyData (vtkDataSet inputGrd, vtkDataArray clipAray, double isoValue, vtkUnstructuredGrid *outputUG)

void	ClipRectilinearGridData (vtkDataSet inputGrd, vtkDataArray clipAray, double isoValue, vtkUnstructuredGrid *outputUG)

void	ClipStructuredGridData (vtkDataSet inputGrd, vtkDataArray clipAray, double isoValue, vtkUnstructuredGrid *outputUG)

void	ClipUnstructuredGridData (vtkDataSet inputGrd, vtkDataArray clipAray, double isoValue, vtkUnstructuredGrid *outputUG)
Static Protected Member Functions

static void	InternalProgressCallbackFunction (vtkObject , unsigned long, void clientdata, void *)
Protected Attributes
int	InsideOut
int	GenerateClipScalars
int	GenerateClippedOutput
bool	UseValueAsOffset
double	Value
double	MergeTolerance
vtkCallbackCommand *	InternalProgressObserver
vtkImplicitFunction *	ClipFunction
vtkIncrementalPointLocator *	Locator

Member Typedef Documentation

typedef vtkUnstructuredGridAlgorithm vtkTableBasedClipDataSet::Superclass

Reimplemented from vtkUnstructuredGridAlgorithm.

Definition at line 104 of file vtkTableBasedClipDataSet.h.

Constructor & Destructor Documentation

vtkTableBasedClipDataSet::vtkTableBasedClipDataSet ( vtkImplicitFunction * cf = NULL ) [protected]

Overridden to process REQUEST_UPDATE_EXTENT_INFORMATION.

vtkTableBasedClipDataSet::~vtkTableBasedClipDataSet ( ) [protected]

Overridden to process REQUEST_UPDATE_EXTENT_INFORMATION.

Member Function Documentation

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

Reimplemented from vtkUnstructuredGridAlgorithm.

static int vtkTableBasedClipDataSet::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 vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkUnstructuredGridAlgorithm.

virtual int vtkTableBasedClipDataSet::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 vtkUnstructuredGridAlgorithm.

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

Reimplemented from vtkUnstructuredGridAlgorithm.

void vtkTableBasedClipDataSet::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 vtkUnstructuredGridAlgorithm.

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

Create an instance with a user-specified implicit function, turning off IVARs InsideOut and GenerateClipScalars and setting IVAR Value to 0.0.

Reimplemented from vtkUnstructuredGridAlgorithm.

unsigned long vtkTableBasedClipDataSet::GetMTime ( ) [virtual]

Get the MTime for which the point locator and clip function are consdiered.

Reimplemented from vtkObject.

virtual void vtkTableBasedClipDataSet::SetInsideOut ( int ) [virtual]

Set/Get the InsideOut flag. With this flag off, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is greater than IVAR Value. With this flag on, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is less than or equal to IVAR Value. This flag is off by default.

virtual int vtkTableBasedClipDataSet::GetInsideOut ( ) [virtual]

Set/Get the InsideOut flag. With this flag off, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is greater than IVAR Value. With this flag on, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is less than or equal to IVAR Value. This flag is off by default.

virtual void vtkTableBasedClipDataSet::InsideOutOn ( ) [virtual]

Set/Get the InsideOut flag. With this flag off, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is greater than IVAR Value. With this flag on, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is less than or equal to IVAR Value. This flag is off by default.

virtual void vtkTableBasedClipDataSet::InsideOutOff ( ) [virtual]

Set/Get the InsideOut flag. With this flag off, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is greater than IVAR Value. With this flag on, a vertex is considered inside (the implicit function or the isosurface) if the (function or scalar) value is less than or equal to IVAR Value. This flag is off by default.

virtual void vtkTableBasedClipDataSet::SetValue ( double ) [virtual]

Set/Get the clipping value of the implicit function (if an implicit function is applied) or scalar data array (if a scalar data array is used), with 0.0 as the default value. This value is ignored if flag UseValueAsOffset is true AND a clip function is defined.

virtual double vtkTableBasedClipDataSet::GetValue ( ) [virtual]

Set/Get the clipping value of the implicit function (if an implicit function is applied) or scalar data array (if a scalar data array is used), with 0.0 as the default value. This value is ignored if flag UseValueAsOffset is true AND a clip function is defined.

virtual void vtkTableBasedClipDataSet::SetUseValueAsOffset ( bool ) [virtual]

Set/Get flag UseValueAsOffset, with true as the default value. With this flag on, IVAR Value is used as an offset parameter to the implicit function. Value is used only when clipping using a scalar array.

virtual bool vtkTableBasedClipDataSet::GetUseValueAsOffset ( ) [virtual]

Set/Get flag UseValueAsOffset, with true as the default value. With this flag on, IVAR Value is used as an offset parameter to the implicit function. Value is used only when clipping using a scalar array.

virtual void vtkTableBasedClipDataSet::UseValueAsOffsetOn ( ) [virtual]

Set/Get flag UseValueAsOffset, with true as the default value. With this flag on, IVAR Value is used as an offset parameter to the implicit function. Value is used only when clipping using a scalar array.

virtual void vtkTableBasedClipDataSet::UseValueAsOffsetOff ( ) [virtual]

Set/Get flag UseValueAsOffset, with true as the default value. With this flag on, IVAR Value is used as an offset parameter to the implicit function. Value is used only when clipping using a scalar array.

virtual void vtkTableBasedClipDataSet::SetClipFunction ( vtkImplicitFunction * ) [virtual]

Set/Get the implicit function with which to perform the clipping operation. Unless an implicit function is defined, the specified input scalar data will be used for clipping.

virtual vtkImplicitFunction* vtkTableBasedClipDataSet::GetClipFunction ( ) [virtual]

Set/Get the implicit function with which to perform the clipping operation. Unless an implicit function is defined, the specified input scalar data will be used for clipping.

virtual void vtkTableBasedClipDataSet::SetGenerateClipScalars ( int ) [virtual]

Set/Get flag GenerateClipScalars, with 0 as the default value. With this flag on, the scalar point data values obtained by evaluating the implicit function will be exported to the output. Note that this flag requries that an implicit function be provided.

virtual int vtkTableBasedClipDataSet::GetGenerateClipScalars ( ) [virtual]

Set/Get flag GenerateClipScalars, with 0 as the default value. With this flag on, the scalar point data values obtained by evaluating the implicit function will be exported to the output. Note that this flag requries that an implicit function be provided.

virtual void vtkTableBasedClipDataSet::GenerateClipScalarsOn ( ) [virtual]

Set/Get flag GenerateClipScalars, with 0 as the default value. With this flag on, the scalar point data values obtained by evaluating the implicit function will be exported to the output. Note that this flag requries that an implicit function be provided.

virtual void vtkTableBasedClipDataSet::GenerateClipScalarsOff ( ) [virtual]

Set/Get flag GenerateClipScalars, with 0 as the default value. With this flag on, the scalar point data values obtained by evaluating the implicit function will be exported to the output. Note that this flag requries that an implicit function be provided.

void vtkTableBasedClipDataSet::SetLocator ( vtkIncrementalPointLocator * locator )

Set/Get a point locator locator for merging duplicate points. By default, an instance of vtkMergePoints is used. Note that this IVAR is provided in this class only because this filter may resort to its sibling class vtkClipDataSet when processing some special grids (such as cylinders or cones with capping faces in the form of a vtkPolyData) while the latter requires a point locator. This filter itself does not need a locator.

virtual vtkIncrementalPointLocator* vtkTableBasedClipDataSet::GetLocator ( ) [virtual]

Set/Get a point locator locator for merging duplicate points. By default, an instance of vtkMergePoints is used. Note that this IVAR is provided in this class only because this filter may resort to its sibling class vtkClipDataSet when processing some special grids (such as cylinders or cones with capping faces in the form of a vtkPolyData) while the latter requires a point locator. This filter itself does not need a locator.

virtual void vtkTableBasedClipDataSet::SetMergeTolerance ( double ) [virtual]

Set/Get the tolerance used for merging duplicate points near the clipping intersection cells. This tolerance may prevent the generation of degenerate primitives. Note that only 3D cells actually use this IVAR.

virtual double vtkTableBasedClipDataSet::GetMergeTolerance ( ) [virtual]

Set/Get the tolerance used for merging duplicate points near the clipping intersection cells. This tolerance may prevent the generation of degenerate primitives. Note that only 3D cells actually use this IVAR.

void vtkTableBasedClipDataSet::CreateDefaultLocator ( )

Create a default point locator when none is specified. The point locator is used to merge coincident points.

virtual void vtkTableBasedClipDataSet::SetGenerateClippedOutput ( int ) [virtual]

Set/Get whether a second output is generated. The second output contains the polygonal data that is clipped away by the iso-surface.

virtual int vtkTableBasedClipDataSet::GetGenerateClippedOutput ( ) [virtual]

Set/Get whether a second output is generated. The second output contains the polygonal data that is clipped away by the iso-surface.

virtual void vtkTableBasedClipDataSet::GenerateClippedOutputOn ( ) [virtual]

Set/Get whether a second output is generated. The second output contains the polygonal data that is clipped away by the iso-surface.

virtual void vtkTableBasedClipDataSet::GenerateClippedOutputOff ( ) [virtual]

Set/Get whether a second output is generated. The second output contains the polygonal data that is clipped away by the iso-surface.

vtkUnstructuredGrid* vtkTableBasedClipDataSet::GetClippedOutput ( )

Return the clipped output.

virtual int vtkTableBasedClipDataSet::ProcessRequest	(	vtkInformation *	,
		vtkInformationVector **	,
		vtkInformationVector *
	)			`[virtual]`

Overridden to process REQUEST_UPDATE_EXTENT_INFORMATION.

Reimplemented from vtkUnstructuredGridAlgorithm.

virtual int vtkTableBasedClipDataSet::RequestData	(	vtkInformation *	request,
		vtkInformationVector **	inputVector,
		vtkInformationVector *	outputVector
	)			`[protected, virtual]`

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

Reimplemented from vtkUnstructuredGridAlgorithm.

virtual int vtkTableBasedClipDataSet::FillInputPortInformation	(	int	port,
		vtkInformation *	info
	)			`[protected, virtual]`

Fill the input port information objects for this algorithm. This is invoked by the first call to GetInputPortInformation for each port so subclasses can specify what they can handle.

Reimplemented from vtkUnstructuredGridAlgorithm.

void vtkTableBasedClipDataSet::ClipDataSet	(	vtkDataSet *	pDataSet,
		vtkDataArray *	clipAray,
		vtkUnstructuredGrid *	unstruct
	)			`[protected]`

This function resorts to the sibling class vtkClipDataSet to handle special grids (such as cylinders or cones with capping faces in the form a vtkPolyData).

void vtkTableBasedClipDataSet::ClipImageData	(	vtkDataSet *	inputGrd,
		vtkDataArray *	clipAray,
		double	isoValue,
		vtkUnstructuredGrid *	outputUG
	)			`[protected]`

This function takes a vtkImageData as a vtkRectilinearGrid, which is then clipped by ClipRectilinearGridData(......).

void vtkTableBasedClipDataSet::ClipPolyData	(	vtkDataSet *	inputGrd,
		vtkDataArray *	clipAray,
		double	isoValue,
		vtkUnstructuredGrid *	outputUG
	)			`[protected]`

This function clips a vtkPolyData object based on a specified iso-value (isoValue) using a scalar point data array (clipAray) that is either just an input scalar point data array or the result of evaluating an implicit function (provided via SetClipFunction()). The clipping result is exported to outputUG.

void vtkTableBasedClipDataSet::ClipRectilinearGridData	(	vtkDataSet *	inputGrd,
		vtkDataArray *	clipAray,
		double	isoValue,
		vtkUnstructuredGrid *	outputUG
	)			`[protected]`

This function clips a vtkRectilinearGrid based on a specified iso-value (isoValue) using a scalar point data array (clipAray) that is either just an input scalar point data array or the result of evaluating an implicit function (provided via SetClipFunction()). The clipping result is exported to outputUG.

void vtkTableBasedClipDataSet::ClipStructuredGridData	(	vtkDataSet *	inputGrd,
		vtkDataArray *	clipAray,
		double	isoValue,
		vtkUnstructuredGrid *	outputUG
	)			`[protected]`

This function clips a vtkStructuredGrid based on a specified iso-value (isoValue) using a scalar point data array (clipAray) that is either just an input scalar point data array or the result of evaluating an implicit function (provided via SetClipFunction()). The clipping result is exported to outputUG.

void vtkTableBasedClipDataSet::ClipUnstructuredGridData	(	vtkDataSet *	inputGrd,
		vtkDataArray *	clipAray,
		double	isoValue,
		vtkUnstructuredGrid *	outputUG
	)			`[protected]`

This function clips a vtkUnstructuredGrid based on a specified iso-value (isoValue) using a scalar point data array (clipAray) that is either just an input scalar point data array or the result of evaluating an implicit function (provided via SetClipFunction()). The clipping result is exported to outputUG.