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vtkImplicitModeller Class Reference

compute distance from input geometry on structured point dataset. More...

#include <vtkImplicitModeller.h>

Inheritance diagram for vtkImplicitModeller:

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Collaboration diagram for vtkImplicitModeller:

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List of all members.

Public Methods

virtual const char * GetClassName ()
virtual int IsA (const char *type)
void PrintSelf (ostream &os, vtkIndent indent)
float ComputeModelBounds (vtkDataSet *input=NULL)
virtual int * GetSampleDimensions ()
virtual void GetSampleDimensions (int data[3])
void SetSampleDimensions (int i, int j, int k)
void SetSampleDimensions (int dim[3])
virtual void SetMaximumDistance (float)
virtual float GetMaximumDistance ()
virtual void SetModelBounds (float, float, float, float, float, float)
virtual void SetModelBounds (float[6])
virtual float * GetModelBounds ()
virtual void GetModelBounds (float data[6])
virtual void SetAdjustBounds (int)
virtual int GetAdjustBounds ()
virtual void AdjustBoundsOn ()
virtual void AdjustBoundsOff ()
virtual void SetAdjustDistance (float)
virtual float GetAdjustDistance ()
virtual void SetCapping (int)
virtual int GetCapping ()
virtual void CappingOn ()
virtual void CappingOff ()
virtual void SetCapValue (float)
virtual float GetCapValue ()
virtual void SetProcessMode (int)
virtual int GetProcessMode ()
void SetProcessModeToPerVoxel ()
void SetProcessModeToPerCell ()
const char * GetProcessModeAsString (void)
virtual void SetLocatorMaxLevel (int)
virtual int GetLocatorMaxLevel ()
virtual void SetNumberOfThreads (int)
virtual int GetNumberOfThreads ()
void StartAppend ()
void Append (vtkDataSet *input)
void EndAppend ()
virtual void UpdateData (vtkDataObject *output)

Static Public Methods

int IsTypeOf (const char *type)
vtkImplicitModeller * SafeDownCast (vtkObject *o)
vtkImplicitModeller * New ()

Protected Methods

 vtkImplicitModeller ()
 ~vtkImplicitModeller ()
 vtkImplicitModeller (const vtkImplicitModeller &)
void operator= (const vtkImplicitModeller &)
void Execute ()
void ExecuteInformation ()
void Cap (vtkScalars *s)

Protected Attributes

int NumberOfThreads
int SampleDimensions [3]
float MaximumDistance
float ModelBounds [6]
int Capping
float CapValue
int DataAppended
int AdjustBounds
float AdjustDistance
int ProcessMode
int LocatorMaxLevel
int BoundsComputed
float InternalMaxDistance

Detailed Description

compute distance from input geometry on structured point dataset.

2000/12/10 20:08:39

vtkImplicitModeller is a filter that computes the distance from the input geometry to the points of an output structured point set. This distance function can then be "contoured" to generate new, offset surfaces from the original geometry. An important feature of this object is "capping". If capping is turned on, after the implicit model is created, the values on the boundary of the structured points dataset are set to the cap value. This is used to force closure of the resulting contoured surface. Note, however, that large cap values can generate weird surface normals in those cells adjacent to the boundary of the dataset. Using smaller cap value will reduce this effect.

Another important ivar is MaximumDistance. This controls how far into the volume the distance function is computed from the input geometry. Small values give significant increases in performance. However, there can strange sampling effects at the extreme range of the MaximumDistance.

In order to properly execute and sample the input data, a rectangular region in space must be defined (this is the ivar ModelBounds). If not explicitly defined, the model bounds will be computed. Note that to avoid boundary effects, it is possible to adjust the model bounds (i.e., using the AdjustBounds and AdjustDistance ivars) to strictly contain the sampled data.

This filter has one other unusual capability: it is possible to append data in a sequence of operations to generate a single output. This is useful when you have multiple datasets and want to create a conglomeration of all the data. However, the user must be careful to either specify the ModelBounds or specify the first item such that its bounds completely contain all other items. This is because the rectangular region of the output can not be changed after the 1st Append.

The ProcessMode ivar controls the method used within the Append function (where the actual work is done regardless if the Append function is explicitly called) to compute the implicit model. If set to work in voxel mode, each voxel is visited once. If set to cell mode, each cell is visited once. Tests have shown once per voxel to be faster when there are a lot of cells (at least a thousand?); relative performance improvement increases with addition cells. Primitives should not be stripped for best performance of the voxel mode. Also, if explicitly using the Append feature many times, the cell mode will probably be better because each voxel will be visited each Append. Append the data before input if possible when using the voxel mode.

Further performance improvement is now possible using the PerVoxel process mode on multi-processor machines (the mode is now multithreaded). Each thread processes a different "slab" of the output. Also, if the input is vtkPolyData, it is appropriately clipped for each thread; that is, each thread only considers the input which could affect its slab of the output.

See also:
vtkSampleFunction vtkContourFilter
vtkImplicitModeller (examples)

Definition at line 112 of file vtkImplicitModeller.h.

Constructor & Destructor Documentation

vtkImplicitModeller::vtkImplicitModeller   [protected]

vtkImplicitModeller::~vtkImplicitModeller   [protected]

vtkImplicitModeller::vtkImplicitModeller const vtkImplicitModeller &    [inline, protected]

Definition at line 208 of file vtkImplicitModeller.h.

Member Function Documentation

virtual const char* vtkImplicitModeller::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 vtkDataSetToStructuredPointsFilter.

int vtkImplicitModeller::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 vtkDataSetToStructuredPointsFilter.

virtual int vtkImplicitModeller::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 vtkDataSetToStructuredPointsFilter.

vtkImplicitModeller* vtkImplicitModeller::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 vtkDataSetToStructuredPointsFilter.

void vtkImplicitModeller::PrintSelf ostream &    os,
vtkIndent    indent

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 vtkSource.

vtkImplicitModeller* vtkImplicitModeller::New   [static]

Construct with sample dimensions=(50,50,50), and so that model bounds are automatically computed from the input. Capping is turned on with CapValue equal to a large positive number.

Reimplemented from vtkStructuredPointsSource.

float vtkImplicitModeller::ComputeModelBounds vtkDataSet   input = NULL

Compute ModelBounds from input geometry. If input is not specified, the input of the filter will be used.

virtual int* vtkImplicitModeller::GetSampleDimensions   [virtual]

Set/Get the i-j-k dimensions on which to sample distance function.

virtual void vtkImplicitModeller::GetSampleDimensions int    data[3] [virtual]

void vtkImplicitModeller::SetSampleDimensions int    i,
int    j,
int    k

void vtkImplicitModeller::SetSampleDimensions int    dim[3]

virtual void vtkImplicitModeller::SetMaximumDistance float    [virtual]

Set / get the distance away from surface of input geometry to sample. Smaller values make large increases in performance.

virtual float vtkImplicitModeller::GetMaximumDistance   [virtual]

virtual void vtkImplicitModeller::SetModelBounds float   ,
float   ,
float   ,
float   ,
float   ,

Set / get the region in space in which to perform the sampling. If not specified, it will be computed automatically.

virtual void vtkImplicitModeller::SetModelBounds float   [6] [virtual]

virtual float* vtkImplicitModeller::GetModelBounds   [virtual]

virtual void vtkImplicitModeller::GetModelBounds float    data[6] [virtual]

virtual void vtkImplicitModeller::SetAdjustBounds int    [virtual]

Control how the model bounds are computed. If the ivar AdjustBounds is set, then the bounds specified (or computed automatically) is modified by the fraction given by AdjustDistance. This means that the model bounds is expanded in each of the x-y-z directions.

virtual int vtkImplicitModeller::GetAdjustBounds   [virtual]

virtual void vtkImplicitModeller::AdjustBoundsOn   [virtual]

virtual void vtkImplicitModeller::AdjustBoundsOff   [virtual]

virtual void vtkImplicitModeller::SetAdjustDistance float    [virtual]

Specify the amount to grow the model bounds (if the ivar AdjustBounds is set). The value is a fraction of the maximum length of the sides of the box specified by the model bounds.

virtual float vtkImplicitModeller::GetAdjustDistance   [virtual]

virtual void vtkImplicitModeller::SetCapping int    [virtual]

The outer boundary of the structured point set can be assigned a particular value. This can be used to close or "cap" all surfaces.

virtual int vtkImplicitModeller::GetCapping   [virtual]

virtual void vtkImplicitModeller::CappingOn   [virtual]

virtual void vtkImplicitModeller::CappingOff   [virtual]

virtual void vtkImplicitModeller::SetCapValue float    [virtual]

Specify the capping value to use. The CapValue is also used as an initial distance value at each point in the dataset.

virtual float vtkImplicitModeller::GetCapValue   [virtual]

virtual void vtkImplicitModeller::SetProcessMode int    [virtual]

Specify whether to visit each cell once per append or each voxel once per append. Some tests have shown once per voxel to be faster when there are a lot of cells (at least a thousand?); relative performance improvement increases with addition cells. Primitives should not be stripped for best performance of the voxel mode.

virtual int vtkImplicitModeller::GetProcessMode   [virtual]

void vtkImplicitModeller::SetProcessModeToPerVoxel   [inline]

Definition at line 174 of file vtkImplicitModeller.h.

void vtkImplicitModeller::SetProcessModeToPerCell   [inline]

Definition at line 175 of file vtkImplicitModeller.h.

const char* vtkImplicitModeller::GetProcessModeAsString void   

virtual void vtkImplicitModeller::SetLocatorMaxLevel int    [virtual]

Specify the level of the locator to use when using the per voxel process mode.

virtual int vtkImplicitModeller::GetLocatorMaxLevel   [virtual]

virtual void vtkImplicitModeller::SetNumberOfThreads int    [virtual]

Set / Get the number of threads used during Per-Voxel processing mode

virtual int vtkImplicitModeller::GetNumberOfThreads   [virtual]

void vtkImplicitModeller::StartAppend  

Initialize the filter for appending data. You must invoke the StartAppend() method before doing successive Appends(). It's also a good idea to manually specify the model bounds; otherwise the input bounds for the data will be used.

void vtkImplicitModeller::Append vtkDataSet   input

Append a data set to the existing output. To use this function, you'll have to invoke the StartAppend() method before doing successive appends. It's also a good idea to specify the model bounds; otherwise the input model bounds is used. When you've finished appending, use the EndAppend() method.

void vtkImplicitModeller::EndAppend  

Method completes the append process.

virtual void vtkImplicitModeller::UpdateData vtkDataObject   output [virtual]

Reimplemented from vtkSource.

void vtkImplicitModeller::operator= const vtkImplicitModeller &    [inline, protected]

Definition at line 209 of file vtkImplicitModeller.h.

void vtkImplicitModeller::Execute   [protected, virtual]

Reimplemented from vtkSource.

void vtkImplicitModeller::ExecuteInformation   [protected, virtual]

Reimplemented from vtkStructuredPointsSource.

void vtkImplicitModeller::Cap vtkScalars   s [protected]

Member Data Documentation

vtkMultiThreader* vtkImplicitModeller::Threader [protected]

Definition at line 216 of file vtkImplicitModeller.h.

int vtkImplicitModeller::NumberOfThreads [protected]

Definition at line 217 of file vtkImplicitModeller.h.

int vtkImplicitModeller::SampleDimensions[3] [protected]

Definition at line 219 of file vtkImplicitModeller.h.

float vtkImplicitModeller::MaximumDistance [protected]

Definition at line 220 of file vtkImplicitModeller.h.

float vtkImplicitModeller::ModelBounds[6] [protected]

Definition at line 221 of file vtkImplicitModeller.h.

int vtkImplicitModeller::Capping [protected]

Definition at line 222 of file vtkImplicitModeller.h.

float vtkImplicitModeller::CapValue [protected]

Definition at line 223 of file vtkImplicitModeller.h.

int vtkImplicitModeller::DataAppended [protected]

Definition at line 224 of file vtkImplicitModeller.h.

int vtkImplicitModeller::AdjustBounds [protected]

Definition at line 225 of file vtkImplicitModeller.h.

float vtkImplicitModeller::AdjustDistance [protected]

Definition at line 226 of file vtkImplicitModeller.h.

int vtkImplicitModeller::ProcessMode [protected]

Definition at line 227 of file vtkImplicitModeller.h.

int vtkImplicitModeller::LocatorMaxLevel [protected]

Definition at line 228 of file vtkImplicitModeller.h.

int vtkImplicitModeller::BoundsComputed [protected]

Definition at line 230 of file vtkImplicitModeller.h.

float vtkImplicitModeller::InternalMaxDistance [protected]

Definition at line 231 of file vtkImplicitModeller.h.

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