Public Member Functions |
| vtkWindowedSincPolyDataFilter (IntPtr rawCppThis, bool callDisposalMethod, bool strong) |
| Automatically generated constructor - called from generated code. DO NOT call directly.
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| vtkWindowedSincPolyDataFilter () |
| Construct object with number of iterations 20; passband .1; feature edge smoothing turned off; feature angle 45 degrees; edge angle 15 degrees; and boundary smoothing turned on. Error scalars and vectors are not generated (by default). The convergence criterion is 0.0 of the bounding box diagonal.
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virtual void | BoundarySmoothingOff () |
| Turn on/off the smoothing of vertices on the boundary of the mesh.
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virtual void | BoundarySmoothingOn () |
| Turn on/off the smoothing of vertices on the boundary of the mesh.
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virtual void | FeatureEdgeSmoothingOff () |
| Turn on/off smoothing along sharp interior edges.
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virtual void | FeatureEdgeSmoothingOn () |
| Turn on/off smoothing along sharp interior edges.
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virtual void | GenerateErrorScalarsOff () |
| Turn on/off the generation of scalar distance values.
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virtual void | GenerateErrorScalarsOn () |
| Turn on/off the generation of scalar distance values.
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virtual void | GenerateErrorVectorsOff () |
| Turn on/off the generation of error vectors.
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virtual void | GenerateErrorVectorsOn () |
| Turn on/off the generation of error vectors.
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virtual int | GetBoundarySmoothing () |
| Turn on/off the smoothing of vertices on the boundary of the mesh.
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virtual double | GetEdgeAngle () |
| Specify the edge angle to control smoothing along edges (either interior or boundary).
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virtual double | GetEdgeAngleMaxValue () |
| Specify the edge angle to control smoothing along edges (either interior or boundary).
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virtual double | GetEdgeAngleMinValue () |
| Specify the edge angle to control smoothing along edges (either interior or boundary).
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virtual double | GetFeatureAngle () |
| Specify the feature angle for sharp edge identification.
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virtual double | GetFeatureAngleMaxValue () |
| Specify the feature angle for sharp edge identification.
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virtual double | GetFeatureAngleMinValue () |
| Specify the feature angle for sharp edge identification.
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virtual int | GetFeatureEdgeSmoothing () |
| Turn on/off smoothing along sharp interior edges.
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virtual int | GetGenerateErrorScalars () |
| Turn on/off the generation of scalar distance values.
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virtual int | GetGenerateErrorVectors () |
| Turn on/off the generation of error vectors.
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virtual int | GetNonManifoldSmoothing () |
| Smooth non-manifold vertices.
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virtual int | GetNormalizeCoordinates () |
| Turn on/off coordinate normalization. The positions can be translated and scaled such that they fit within a [-1, 1] prior to the smoothing computation. The default is off. The numerical stability of the solution can be improved by turning normalization on. If normalization is on, the coordinates will be rescaled to the original coordinate system after smoothing has completed.
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virtual int | GetNumberOfIterations () |
| Specify the number of iterations (or degree of the polynomial approximating the windowed sinc function).
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virtual int | GetNumberOfIterationsMaxValue () |
| Specify the number of iterations (or degree of the polynomial approximating the windowed sinc function).
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virtual int | GetNumberOfIterationsMinValue () |
| Specify the number of iterations (or degree of the polynomial approximating the windowed sinc function).
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virtual double | GetPassBand () |
| Set the passband value for the windowed sinc filter
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virtual double | GetPassBandMaxValue () |
| Set the passband value for the windowed sinc filter
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virtual double | GetPassBandMinValue () |
| Set the passband value for the windowed sinc filter
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override int | IsA (string type) |
| Undocumented Block
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new vtkWindowedSincPolyDataFilter | NewInstance () |
| Undocumented Block
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virtual void | NonManifoldSmoothingOff () |
| Smooth non-manifold vertices.
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virtual void | NonManifoldSmoothingOn () |
| Smooth non-manifold vertices.
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virtual void | NormalizeCoordinatesOff () |
| Turn on/off coordinate normalization. The positions can be translated and scaled such that they fit within a [-1, 1] prior to the smoothing computation. The default is off. The numerical stability of the solution can be improved by turning normalization on. If normalization is on, the coordinates will be rescaled to the original coordinate system after smoothing has completed.
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virtual void | NormalizeCoordinatesOn () |
| Turn on/off coordinate normalization. The positions can be translated and scaled such that they fit within a [-1, 1] prior to the smoothing computation. The default is off. The numerical stability of the solution can be improved by turning normalization on. If normalization is on, the coordinates will be rescaled to the original coordinate system after smoothing has completed.
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virtual void | SetBoundarySmoothing (int _arg) |
| Turn on/off the smoothing of vertices on the boundary of the mesh.
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virtual void | SetEdgeAngle (double _arg) |
| Specify the edge angle to control smoothing along edges (either interior or boundary).
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virtual void | SetFeatureAngle (double _arg) |
| Specify the feature angle for sharp edge identification.
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virtual void | SetFeatureEdgeSmoothing (int _arg) |
| Turn on/off smoothing along sharp interior edges.
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virtual void | SetGenerateErrorScalars (int _arg) |
| Turn on/off the generation of scalar distance values.
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virtual void | SetGenerateErrorVectors (int _arg) |
| Turn on/off the generation of error vectors.
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virtual void | SetNonManifoldSmoothing (int _arg) |
| Smooth non-manifold vertices.
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virtual void | SetNormalizeCoordinates (int _arg) |
| Turn on/off coordinate normalization. The positions can be translated and scaled such that they fit within a [-1, 1] prior to the smoothing computation. The default is off. The numerical stability of the solution can be improved by turning normalization on. If normalization is on, the coordinates will be rescaled to the original coordinate system after smoothing has completed.
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virtual void | SetNumberOfIterations (int _arg) |
| Specify the number of iterations (or degree of the polynomial approximating the windowed sinc function).
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virtual void | SetPassBand (double _arg) |
| Set the passband value for the windowed sinc filter
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| vtkPolyDataAlgorithm (IntPtr rawCppThis, bool callDisposalMethod, bool strong) |
| Automatically generated constructor - called from generated code. DO NOT call directly.
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| vtkPolyDataAlgorithm () |
| Undocumented Block
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void | AddInput (vtkDataObject arg0) |
| Add an input of this algorithm. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::AddInputConnection(). See SetInput() for details.
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void | AddInput (int arg0, vtkDataObject arg1) |
| Add an input of this algorithm. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::AddInputConnection(). See SetInput() for details.
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vtkDataObject | GetInput () |
| this method is not recommended for use, but lots of old style filters use it
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vtkDataObject | GetInput (int port) |
| this method is not recommended for use, but lots of old style filters use it
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vtkPolyData | GetOutput () |
| Get the output data object for a port on this algorithm.
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vtkPolyData | GetOutput (int arg0) |
| Get the output data object for a port on this algorithm.
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vtkPolyData | GetPolyDataInput (int port) |
| this method is not recommended for use, but lots of old style filters use it
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void | SetInput (vtkDataObject arg0) |
| Set an input of this algorithm. You should not override these methods because they are not the only way to connect a pipeline. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::SetInputConnection(). These methods transform the input index to the input port index, not an index of a connection within a single port.
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void | SetInput (int arg0, vtkDataObject arg1) |
| Set an input of this algorithm. You should not override these methods because they are not the only way to connect a pipeline. Note that these methods support old-style pipeline connections. When writing new code you should use the more general vtkAlgorithm::SetInputConnection(). These methods transform the input index to the input port index, not an index of a connection within a single port.
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virtual void | SetOutput (vtkDataObject d) |
| Get the output data object for a port on this algorithm.
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| vtkAlgorithm (IntPtr rawCppThis, bool callDisposalMethod, bool strong) |
| Automatically generated constructor - called from generated code. DO NOT call directly.
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| vtkAlgorithm () |
| Undocumented Block
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override void | Register (vtkObjectBase o) |
| Participate in garbage collection.
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virtual void | AbortExecuteOff () |
| Set/Get the AbortExecute flag for the process object. Process objects may handle premature termination of execution in different ways.
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virtual void | AbortExecuteOn () |
| Set/Get the AbortExecute flag for the process object. Process objects may handle premature termination of execution in different ways.
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virtual void | AddInputConnection (int port, vtkAlgorithmOutput input) |
| Add a connection to the given input port index. See SetInputConnection() for details on input connections. This method is the complement to RemoveInputConnection() in that it adds only the connection specified without affecting other connections. Typical usage is
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virtual void | AddInputConnection (vtkAlgorithmOutput input) |
| Add a connection to the given input port index. See SetInputConnection() for details on input connections. This method is the complement to RemoveInputConnection() in that it adds only the connection specified without affecting other connections. Typical usage is
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virtual double | ComputePriority () |
| Returns the priority of the piece described by the current update extent. The priority is a number between 0.0 and 1.0 with 0 meaning skippable (REQUEST_DATA not needed) and 1.0 meaning important.
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void | ConvertTotalInputToPortConnection (int ind, ref int port, ref int conn) |
| Convenience routine to convert from a linear ordering of input connections to a port/connection pair.
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virtual int | GetAbortExecute () |
| Set/Get the AbortExecute flag for the process object. Process objects may handle premature termination of execution in different ways.
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virtual uint | GetErrorCode () |
| The error code contains a possible error that occured while reading or writing the file.
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vtkExecutive | GetExecutive () |
| Get this algorithm's executive. If it has none, a default executive will be created.
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virtual vtkInformation | GetInformation () |
| Set/Get the information object associated with this algorithm.
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vtkInformation | GetInputArrayInformation (int idx) |
| Get the info object for the specified input array to this algorithm
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vtkAlgorithmOutput | GetInputConnection (int port, int index) |
| Get the algorithm output port connected to an input port.
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vtkDataObject | GetInputDataObject (int port, int connection) |
| Get the data object that will contain the algorithm input for the given port and given connection.
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vtkInformation | GetInputPortInformation (int port) |
| Get the information object associated with an input port. There is one input port per kind of input to the algorithm. Each input port tells executives what kind of data and downstream requests this algorithm can handle for that input.
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int | GetNumberOfInputConnections (int port) |
| Get the number of inputs currently connected to a port.
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int | GetNumberOfInputPorts () |
| Get the number of input ports used by the algorithm.
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int | GetNumberOfOutputPorts () |
| Get the number of output ports provided by the algorithm.
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vtkDataObject | GetOutputDataObject (int port) |
| Get the data object that will contain the algorithm output for the given port.
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vtkAlgorithmOutput | GetOutputPort (int index) |
| Get a proxy object corresponding to the given output port of this algorithm. The proxy object can be passed to another algorithm's SetInputConnection(), AddInputConnection(), and RemoveInputConnection() methods to modify pipeline connectivity.
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vtkAlgorithmOutput | GetOutputPort () |
| Get a proxy object corresponding to the given output port of this algorithm. The proxy object can be passed to another algorithm's SetInputConnection(), AddInputConnection(), and RemoveInputConnection() methods to modify pipeline connectivity.
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vtkInformation | GetOutputPortInformation (int port) |
| Get the information object associated with an output port. There is one output port per output from the algorithm. Each output port tells executives what kind of upstream requests this algorithm can handle for that output.
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virtual double | GetProgress () |
| Set/Get the execution progress of a process object.
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virtual double | GetProgressMaxValue () |
| Set/Get the execution progress of a process object.
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virtual double | GetProgressMinValue () |
| Set/Get the execution progress of a process object.
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virtual string | GetProgressText () |
| Set the current text message associated with the progress state. This may be used by a calling process/GUI. Note: Because SetProgressText() is called from inside RequestData() it does not modify the algorithm object. Algorithms are not allowed to modify themselves from inside RequestData().
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virtual int | GetReleaseDataFlag () |
| Turn release data flag on or off for all output ports.
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int | GetTotalNumberOfInputConnections () |
| Get the total number of inputs for this algorithm
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int | HasExecutive () |
| Check whether this algorithm has an assigned executive. This will NOT create a default executive.
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virtual int | ModifyRequest (vtkInformation request, int when) |
| This method gives the algorithm a chance to modify the contents of a request before or after (specified in the when argument) it is forwarded. The default implementation is empty. Returns 1 on success, 0 on failure. When can be either vtkExecutive::BeforeForward or vtkExecutive::AfterForward.
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int | ProcessRequest (vtkInformation request, vtkCollection inInfo, vtkInformationVector outInfo) |
| Version of ProcessRequest() that is wrapped. This converts the collection to an array and calls the other version.
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void | ReleaseDataFlagOff () |
| Turn release data flag on or off for all output ports.
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void | ReleaseDataFlagOn () |
| Turn release data flag on or off for all output ports.
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void | RemoveAllInputs () |
| Remove all the input data.
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virtual void | RemoveInputConnection (int port, vtkAlgorithmOutput input) |
| Remove a connection from the given input port index. See SetInputConnection() for details on input connection. This method is the complement to AddInputConnection() in that it removes only the connection specified without affecting other connections. Typical usage is
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virtual void | SetAbortExecute (int _arg) |
| Set/Get the AbortExecute flag for the process object. Process objects may handle premature termination of execution in different ways.
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virtual void | SetExecutive (vtkExecutive executive) |
| Set this algorithm's executive. This algorithm is removed from any executive to which it has previously been assigned and then assigned to the given executive.
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virtual void | SetInformation (vtkInformation arg0) |
| Set/Get the information object associated with this algorithm.
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virtual void | SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, string name) |
| Set the input data arrays that this algorithm will process. Specifically the idx array that this algorithm will process (starting from 0) is the array on port, connection with the specified association and name or attribute type (such as SCALARS). The fieldAssociation refers to which field in the data object the array is stored. See vtkDataObject::FieldAssociations for detail.
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virtual void | SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, int fieldAttributeType) |
| Set the input data arrays that this algorithm will process. Specifically the idx array that this algorithm will process (starting from 0) is the array on port, connection with the specified association and name or attribute type (such as SCALARS). The fieldAssociation refers to which field in the data object the array is stored. See vtkDataObject::FieldAssociations for detail.
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virtual void | SetInputArrayToProcess (int idx, vtkInformation info) |
| Set the input data arrays that this algorithm will process. Specifically the idx array that this algorithm will process (starting from 0) is the array on port, connection with the specified association and name or attribute type (such as SCALARS). The fieldAssociation refers to which field in the data object the array is stored. See vtkDataObject::FieldAssociations for detail.
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virtual void | SetInputArrayToProcess (int idx, int port, int connection, string fieldAssociation, string attributeTypeorName) |
| String based versions of SetInputArrayToProcess(). Because fieldAssociation and fieldAttributeType are enums, they cannot be easily accessed from scripting language. These methods provides an easy and safe way of passing association and attribute type information. Field association is one of the following:
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virtual void | SetInputConnection (int port, vtkAlgorithmOutput input) |
| Set the connection for the given input port index. Each input port of a filter has a specific purpose. A port may have zero or more connections and the required number is specified by each filter. Setting the connection with this method removes all other connections from the port. To add more than one connection use AddInputConnection().
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virtual void | SetInputConnection (vtkAlgorithmOutput input) |
| Set the connection for the given input port index. Each input port of a filter has a specific purpose. A port may have zero or more connections and the required number is specified by each filter. Setting the connection with this method removes all other connections from the port. To add more than one connection use AddInputConnection().
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virtual void | SetProgress (double _arg) |
| Set/Get the execution progress of a process object.
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void | SetProgressText (string ptext) |
| Set the current text message associated with the progress state. This may be used by a calling process/GUI. Note: Because SetProgressText() is called from inside RequestData() it does not modify the algorithm object. Algorithms are not allowed to modify themselves from inside RequestData().
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virtual void | SetReleaseDataFlag (int arg0) |
| Turn release data flag on or off for all output ports.
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virtual void | Update () |
| Bring this algorithm's outputs up-to-date.
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int | UpdateExtentIsEmpty (vtkDataObject output) |
| This detects when the UpdateExtent will generate no data This condition is satisfied when the UpdateExtent has zero volume (0,-1,...) or the UpdateNumberOfPieces is 0. The source uses this call to determine whether to call Execute.
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int | UpdateExtentIsEmpty (vtkInformation pinfo, int extentType) |
| This detects when the UpdateExtent will generate no data This condition is satisfied when the UpdateExtent has zero volume (0,-1,...) or the UpdateNumberOfPieces is 0. The source uses this call to determine whether to call Execute.
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virtual void | UpdateInformation () |
| Backward compatibility method to invoke UpdateInformation on executive.
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void | UpdateProgress (double amount) |
| Update the progress of the process object. If a ProgressMethod exists, executes it. Then set the Progress ivar to amount. The parameter amount should range between (0,1).
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virtual void | UpdateWholeExtent () |
| Bring this algorithm's outputs up-to-date.
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| vtkObject (IntPtr rawCppThis, bool callDisposalMethod, bool strong) |
| Automatically generated constructor - called from generated code. DO NOT call directly.
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| vtkObject () |
| Create an object with Debug turned off, modified time initialized to zero, and reference counting on.
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uint | AddObserver (uint arg0, vtkCommand arg1, float priority) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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uint | AddObserver (string arg0, vtkCommand arg1, float priority) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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virtual void | DebugOff () |
| Turn debugging output off.
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virtual void | DebugOn () |
| Turn debugging output on.
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vtkCommand | GetCommand (uint tag) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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byte | GetDebug () |
| Get the value of the debug flag.
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virtual uint | GetMTime () |
| Return this object's modified time.
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int | HasObserver (uint arg0, vtkCommand arg1) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | HasObserver (string arg0, vtkCommand arg1) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | HasObserver (uint arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | HasObserver (string arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | InvokeEvent (uint arg0, IntPtr callData) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | InvokeEvent (string arg0, IntPtr callData) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | InvokeEvent (uint arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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int | InvokeEvent (string arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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virtual void | Modified () |
| Update the modification time for this object. Many filters rely on the modification time to determine if they need to recompute their data. The modification time is a unique monotonically increasing unsigned long integer.
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void | RemoveAllObservers () |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObserver (vtkCommand arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObserver (uint tag) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObservers (uint arg0, vtkCommand arg1) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObservers (string arg0, vtkCommand arg1) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObservers (uint arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | RemoveObservers (string arg0) |
| This is a global flag that controls whether any debug, warning or error messages are displayed.
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void | SetDebug (byte debugFlag) |
| Set the value of the debug flag. A non-zero value turns debugging on.
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override string | ToString () |
| Returns the result of calling vtkObject::Print as a C# string.
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delegate void | vtkObjectEventHandler (vtkObject sender, vtkObjectEventArgs e) |
| Generic signature for all vtkObject events.
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void | RemoveAllHandlersForAllEvents () |
| Call RemoveAllHandlers on each non-null vtkObjectEventRelay. TODO: This method needs to get called by the generated Dispose. Make that happen...
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| vtkObjectBase (IntPtr rawCppThis, bool callDisposalMethod, bool strong) |
| Automatically generated constructor - called from generated code. DO NOT call directly.
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| vtkObjectBase () |
| Create an object with Debug turned off, modified time initialized to zero, and reference counting on.
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virtual void | FastDelete () |
| Delete a reference to this object. This version will not invoke garbage collection and can potentially leak the object if it is part of a reference loop. Use this method only when it is known that the object has another reference and would not be collected if a full garbage collection check were done.
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string | GetClassName () |
| Return the class name as a string. This method is defined in all subclasses of vtkObjectBase with the vtkTypeMacro found in vtkSetGet.h.
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int | GetReferenceCount () |
| Return the current reference count of this object.
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void | SetReferenceCount (int arg0) |
| Sets the reference count. (This is very dangerous, use with care.)
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vtkWindowedSincPolyDataFilter - adjust point positions using a windowed sinc function interpolation kernel
Description vtkWindowedSincPolyDataFiler adjust point coordinate using a windowed sinc function interpolation kernel. The effect is to "relax" the mesh, making the cells better shaped and the vertices more evenly distributed. Note that this filter operates the lines, polygons, and triangle strips composing an instance of vtkPolyData. Vertex or poly-vertex cells are never modified.
The algorithm proceeds as follows. For each vertex v, a topological and geometric analysis is performed to determine which vertices are connected to v, and which cells are connected to v. Then, a connectivity array is constructed for each vertex. (The connectivity array is a list of lists of vertices that directly attach to each vertex.) Next, an iteration phase begins over all vertices. For each vertex v, the coordinates of v are modified using a windowed sinc function interpolation kernel. Taubin describes this methodology is the IBM tech report RC-20404 (#90237, dated 3/12/96) "Optimal Surface Smoothing as Filter Design" G. Taubin, T. Zhang and G. Golub. (Zhang and Golub are at Stanford University).
This report discusses using standard signal processing low-pass filters (in particular windowed sinc functions) to smooth polyhedra. The transfer functions of the low-pass filters are approximated by Chebyshev polynomials. This facilitates applying the filters in an iterative diffusion process (as opposed to a kernel convolution). The more smoothing iterations applied, the higher the degree of polynomial approximating the low-pass filter transfer function. Each smoothing iteration, therefore, applies the next higher term of the Chebyshev filter approximation to the polyhedron. This decoupling of the filter into an iteratively applied polynomial is possible since the Chebyshev polynomials are orthogonal, i.e. increasing the order of the approximation to the filter transfer function does not alter the previously calculated coefficients for the low order terms.
Note: Care must be taken to avoid smoothing with too few iterations. A Chebyshev approximation with too few terms is an poor approximation. The first few smoothing iterations represent a severe scaling and translation of the data. Subsequent iterations cause the smoothed polyhedron to converge to the true location and scale of the object. We have attempted to protect against this by automatically adjusting the filter, effectively widening the pass band. This adjustment is only possible if the number of iterations is greater than 1. Note that this sacrifices some degree of smoothing for model integrity. For those interested, the filter is adjusted by searching for a value sigma such that the actual pass band is k_pb + sigma and such that the filter transfer function evaluates to unity at k_pb, i.e. f(k_pb) = 1
To improve the numerical stability of the solution and minimize the scaling the translation effects, the algorithm can translate and scale the position coordinates to within the unit cube [-1, 1], perform the smoothing, and translate and scale the position coordinates back to the original coordinate frame. This mode is controlled with the NormalizeCoordinatesOn() / NormalizeCoordinatesOff() methods. For legacy reasons, the default is NormalizeCoordinatesOff.
This implementation is currently limited to using an interpolation kernel based on Hamming windows. Other windows (such as Hann, Blackman, Kaiser, Lanczos, Gaussian, and exponential windows) could be used instead.
There are some special instance variables used to control the execution of this filter. (These ivars basically control what vertices can be smoothed, and the creation of the connectivity array.) The BoundarySmoothing ivar enables/disables the smoothing operation on vertices that are on the "boundary" of the mesh. A boundary vertex is one that is surrounded by a semi-cycle of polygons (or used by a single line).
Another important ivar is FeatureEdgeSmoothing. If this ivar is enabled, then interior vertices are classified as either "simple", "interior edge", or "fixed", and smoothed differently. (Interior vertices are manifold vertices surrounded by a cycle of polygons; or used by two line cells.) The classification is based on the number of feature edges attached to v. A feature edge occurs when the angle between the two surface normals of a polygon sharing an edge is greater than the FeatureAngle ivar. Then, vertices used by no feature edges are classified "simple", vertices used by exactly two feature edges are classified "interior edge", and all others are "fixed" vertices.
Once the classification is known, the vertices are smoothed differently. Corner (i.e., fixed) vertices are not smoothed at all. Simple vertices are smoothed as before . Interior edge vertices are smoothed only along their two connected edges, and only if the angle between the edges is less than the EdgeAngle ivar.
The total smoothing can be controlled by using two ivars. The NumberOfIterations determines the maximum number of smoothing passes. The NumberOfIterations corresponds to the degree of the polynomial that is used to approximate the windowed sinc function. Ten or twenty iterations is all the is usually necessary. Contrast this with vtkSmoothPolyDataFilter which usually requires 100 to 200 smoothing iterations. vtkSmoothPolyDataFilter is also not an approximation to an ideal low-pass filter, which can cause the geometry to shrink as the amount of smoothing increases.
The second ivar is the specification of the PassBand for the windowed sinc filter. By design, the PassBand is specified as a doubleing point number between 0 and 2. Lower PassBand values produce more smoothing. A good default value for the PassBand is 0.1 (for those interested, the PassBand (and frequencies) for PolyData are based on the valence of the vertices, this limits all the frequency modes in a polyhedral mesh to between 0 and 2.)
There are two instance variables that control the generation of error data. If the ivar GenerateErrorScalars is on, then a scalar value indicating the distance of each vertex from its original position is computed. If the ivar GenerateErrorVectors is on, then a vector representing change in position is computed.
Caveats The smoothing operation reduces high frequency information in the geometry of the mesh. With excessive smoothing important details may be lost. Enabling FeatureEdgeSmoothing helps reduce this effect, but cannot entirely eliminate it.
vtkSmoothPolyDataFilter vtkDecimate vtkDecimatePro