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vtkTableBasedClipDataSet Class Reference

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

#include <vtkTableBasedClipDataSet.h>

Inherits vtkUnstructuredGridAlgorithm.

Public Types

typedef
vtkUnstructuredGridAlgorithm 
Superclass
 

Public Member Functions

virtual int IsA (const char *type)
 
vtkTableBasedClipDataSetNewInstance () const
 
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 ()
 
virtual void SetOutputPointsPrecision (int)
 
virtual int GetOutputPointsPrecision ()
 

Static Public Member Functions

static int IsTypeOf (const char *type)
 
static vtkTableBasedClipDataSetSafeDownCast (vtkObjectBase *o)
 
static vtkTableBasedClipDataSetNew ()
 

Protected Member Functions

virtual vtkObjectBase * NewInstanceInternal () const
 
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
 
int OutputPointsPrecision
 
virtual int ProcessRequest (vtkInformation *, vtkInformationVector **, vtkInformationVector *)
 
 vtkTableBasedClipDataSet (vtkImplicitFunction *cf=NULL)
 
 ~vtkTableBasedClipDataSet ()
 

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
Tests:
vtkTableBasedClipDataSet (Tests)

Definition at line 105 of file vtkTableBasedClipDataSet.h.

Member Typedef Documentation

typedef vtkUnstructuredGridAlgorithm vtkTableBasedClipDataSet::Superclass

Definition at line 108 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

static int vtkTableBasedClipDataSet::IsTypeOf ( const char *  type)
static
virtual int vtkTableBasedClipDataSet::IsA ( const char *  type)
virtual
static vtkTableBasedClipDataSet* vtkTableBasedClipDataSet::SafeDownCast ( vtkObjectBase *  o)
static
virtual vtkObjectBase* vtkTableBasedClipDataSet::NewInstanceInternal ( ) const
protectedvirtual
vtkTableBasedClipDataSet* vtkTableBasedClipDataSet::NewInstance ( ) const
void vtkTableBasedClipDataSet::PrintSelf ( ostream &  os,
vtkIndent  indent 
)
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.

unsigned long vtkTableBasedClipDataSet::GetMTime ( )

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

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 void vtkTableBasedClipDataSet::SetOutputPointsPrecision ( int  )
virtual

Set/get the desired precision for the output types. See the documentation for the vtkAlgorithm::Precision enum for an explanation of the available precision settings.

virtual int vtkTableBasedClipDataSet::GetOutputPointsPrecision ( )
virtual

Set/get the desired precision for the output types. See the documentation for the vtkAlgorithm::Precision enum for an explanation of the available precision settings.

virtual int vtkTableBasedClipDataSet::ProcessRequest ( vtkInformation *  ,
vtkInformationVector **  ,
vtkInformationVector *   
)
virtual

Overridden to process REQUEST_UPDATE_EXTENT_INFORMATION.

virtual int vtkTableBasedClipDataSet::RequestData ( vtkInformation *  ,
vtkInformationVector **  ,
vtkInformationVector *   
)
protectedvirtual
virtual int vtkTableBasedClipDataSet::FillInputPortInformation ( int  port,
vtkInformation *  info 
)
protectedvirtual
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.

static void vtkTableBasedClipDataSet::InternalProgressCallbackFunction ( vtkObject *  ,
unsigned  long,
void *  clientdata,
void *   
)
staticprotected

Register a callback function with the InternalProgressObserver.

void vtkTableBasedClipDataSet::InternalProgressCallback ( vtkAlgorithm *  algorithm)
protected

The actual operation executed by the callback function.

Member Data Documentation

int vtkTableBasedClipDataSet::InsideOut
protected

Definition at line 293 of file vtkTableBasedClipDataSet.h.

int vtkTableBasedClipDataSet::GenerateClipScalars
protected

Definition at line 294 of file vtkTableBasedClipDataSet.h.

int vtkTableBasedClipDataSet::GenerateClippedOutput
protected

Definition at line 295 of file vtkTableBasedClipDataSet.h.

bool vtkTableBasedClipDataSet::UseValueAsOffset
protected

Definition at line 296 of file vtkTableBasedClipDataSet.h.

double vtkTableBasedClipDataSet::Value
protected

Definition at line 297 of file vtkTableBasedClipDataSet.h.

double vtkTableBasedClipDataSet::MergeTolerance
protected

Definition at line 298 of file vtkTableBasedClipDataSet.h.

vtkCallbackCommand* vtkTableBasedClipDataSet::InternalProgressObserver
protected

Definition at line 299 of file vtkTableBasedClipDataSet.h.

vtkImplicitFunction* vtkTableBasedClipDataSet::ClipFunction
protected

Definition at line 300 of file vtkTableBasedClipDataSet.h.

vtkIncrementalPointLocator* vtkTableBasedClipDataSet::Locator
protected

Definition at line 301 of file vtkTableBasedClipDataSet.h.

int vtkTableBasedClipDataSet::OutputPointsPrecision
protected

Definition at line 303 of file vtkTableBasedClipDataSet.h.


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