Compute the finite time Lyapunov exponent (FTLE) of a vector field. More...

#include <LagrangianStructures.h>

Inheritance diagram for vtkm::filter::flow::LagrangianStructures:

Public Member Functions
bool	CanThread () const override
	Returns whether the filter can execute on partitions in concurrent threads. More...

void	SetStepSize (vtkm::FloatDefault s)
	Specifies the step size used for the numerical integrator. More...

vtkm::FloatDefault	GetStepSize ()
	Specifies the step size used for the numerical integrator. More...

void	SetNumberOfSteps (vtkm::Id n)
	Specify the maximum number of steps each particle is allowed to traverse. More...

vtkm::Id	GetNumberOfSteps ()
	Specify the maximum number of steps each particle is allowed to traverse. More...

void	SetAdvectionTime (vtkm::FloatDefault advectionTime)
	Specify the time interval for the advection. More...

vtkm::FloatDefault	GetAdvectionTime ()
	Specify the time interval for the advection. More...

void	SetUseAuxiliaryGrid (bool useAuxiliaryGrid)
	Specify whether to use an auxiliary grid. More...

bool	GetUseAuxiliaryGrid ()
	Specify whether to use an auxiliary grid. More...

void	SetAuxiliaryGridDimensions (vtkm::Id3 auxiliaryDims)
	Specify the dimensions of the auxiliary grid for FTLE calculation. More...

vtkm::Id3	GetAuxiliaryGridDimensions ()
	Specify the dimensions of the auxiliary grid for FTLE calculation. More...

void	SetUseFlowMapOutput (bool useFlowMapOutput)
	Specify whether to use flow maps instead of advection. More...

bool	GetUseFlowMapOutput ()
	Specify whether to use flow maps instead of advection. More...

void	SetOutputFieldName (std::string outputFieldName)
	Specify the name of the output field in the data set returned. More...

std::string	GetOutputFieldName ()
	Specify the name of the output field in the data set returned. More...

void	SetFlowMapOutput (vtkm::cont::ArrayHandle< vtkm::Vec3f > &flowMap)
	Specify the array representing the flow map output to be used for FTLE calculation. More...

vtkm::cont::ArrayHandle< vtkm::Vec3f >	GetFlowMapOutput ()
	Specify the array representing the flow map output to be used for FTLE calculation. More...

Public Member Functions inherited from vtkm::filter::Filter
	Filter ()

virtual	~Filter ()

vtkm::cont::DataSet	Execute (const vtkm::cont::DataSet &input)
	Executes the filter on the input and produces a result dataset. More...

vtkm::cont::PartitionedDataSet	Execute (const vtkm::cont::PartitionedDataSet &input)
	Executes the filter on the input PartitionedDataSet and produces a result PartitionedDataSet. More...

void	SetFieldsToPass (const vtkm::filter::FieldSelection &fieldsToPass)
	Specify which fields get passed from input to output. More...

void	SetFieldsToPass (vtkm::filter::FieldSelection &&fieldsToPass)
	Specify which fields get passed from input to output. More...

void	SetFieldsToPass (const vtkm::filter::FieldSelection &fieldsToPass, vtkm::filter::FieldSelection::Mode mode)

void	SetFieldsToPass (std::initializer_list< std::string > fields, vtkm::filter::FieldSelection::Mode mode=vtkm::filter::FieldSelection::Mode::Select)
	Specify which fields get passed from input to output. More...

void	SetFieldsToPass (std::initializer_list< std::pair< std::string, vtkm::cont::Field::Association >> fields, vtkm::filter::FieldSelection::Mode mode=vtkm::filter::FieldSelection::Mode::Select)
	Specify which fields get passed from input to output. More...

void	SetFieldsToPass (const std::string &fieldname, vtkm::cont::Field::Association association, vtkm::filter::FieldSelection::Mode mode=vtkm::filter::FieldSelection::Mode::Select)
	Specify which fields get passed from input to output. More...

void	SetFieldsToPass (const std::string &fieldname, vtkm::filter::FieldSelection::Mode mode)
	Specify which fields get passed from input to output. More...

const vtkm::filter::FieldSelection &	GetFieldsToPass () const
	Specify which fields get passed from input to output. More...

vtkm::filter::FieldSelection &	GetFieldsToPass ()
	Specify which fields get passed from input to output. More...

void	SetPassCoordinateSystems (bool flag)
	Specify whether to always pass coordinate systems. More...

bool	GetPassCoordinateSystems () const
	Specify whether to always pass coordinate systems. More...

void	SetOutputFieldName (const std::string &name)
	Specifies the name of the output field generated. More...

const std::string &	GetOutputFieldName () const
	Specifies the name of the output field generated. More...

void	SetActiveField (const std::string &name, vtkm::cont::Field::Association association=vtkm::cont::Field::Association::Any)
	Specifies a field to operate on. More...

void	SetActiveField (vtkm::IdComponent index, const std::string &name, vtkm::cont::Field::Association association=vtkm::cont::Field::Association::Any)
	Specifies a field to operate on. More...

const std::string &	GetActiveFieldName (vtkm::IdComponent index=0) const
	Specifies a field to operate on. More...

vtkm::cont::Field::Association	GetActiveFieldAssociation (vtkm::IdComponent index=0) const
	Specifies a field to operate on. More...

void	SetActiveCoordinateSystem (vtkm::Id coord_idx)
	Specifies the coordinate system index to make active to use when processing the input `vtkm::cont::DataSet`. More...

void	SetActiveCoordinateSystem (vtkm::IdComponent index, vtkm::Id coord_idx)
	Specifies the coordinate system index to make active to use when processing the input `vtkm::cont::DataSet`. More...

vtkm::Id	GetActiveCoordinateSystemIndex (vtkm::IdComponent index=0) const
	Specifies the coordinate system index to make active to use when processing the input `vtkm::cont::DataSet`. More...

void	SetUseCoordinateSystemAsField (bool val)
	Specifies whether to use point coordinates as the input field. More...

void	SetUseCoordinateSystemAsField (vtkm::IdComponent index, bool val)
	Specifies whether to use point coordinates as the input field. More...

bool	GetUseCoordinateSystemAsField (vtkm::IdComponent index=0) const
	Specifies whether to use point coordinates as the input field. More...

vtkm::IdComponent	GetNumberOfActiveFields () const
	Return the number of active fields currently set. More...

void	SetThreadsPerCPU (vtkm::Id numThreads)

void	SetThreadsPerGPU (vtkm::Id numThreads)

vtkm::Id	GetThreadsPerCPU () const

vtkm::Id	GetThreadsPerGPU () const

bool	GetRunMultiThreadedFilter () const

void	SetRunMultiThreadedFilter (bool val)

void	SetInvoker (vtkm::cont::Invoker inv)
	Specify the vtkm::cont::Invoker to be used to execute worklets by this filter instance. More...

Private Member Functions
vtkm::cont::DataSet	DoExecute (const vtkm::cont::DataSet &inData) override

Private Attributes
vtkm::FloatDefault	AdvectionTime

vtkm::Id3	AuxiliaryDims

vtkm::cont::ArrayHandle< vtkm::Vec3f >	FlowMapOutput

std::string	OutputFieldName = "FTLE"

vtkm::FloatDefault	StepSize = 1.0f

vtkm::Id	NumberOfSteps = 0

bool	UseAuxiliaryGrid = false

bool	UseFlowMapOutput = false

Additional Inherited Members
Protected Member Functions inherited from vtkm::filter::Filter
vtkm::cont::DataSet	CreateResult (const vtkm::cont::DataSet &inDataSet) const
	Create the output data set for `DoExecute`. More...

vtkm::cont::DataSet	CreateResultField (const vtkm::cont::DataSet &inDataSet, const vtkm::cont::Field &resultField) const
	Create the output data set for `DoExecute` More...

vtkm::cont::DataSet	CreateResultField (const vtkm::cont::DataSet &inDataSet, const std::string &resultFieldName, vtkm::cont::Field::Association resultFieldAssociation, const vtkm::cont::UnknownArrayHandle &resultFieldArray) const
	Create the output data set for `DoExecute` More...

vtkm::cont::DataSet	CreateResultFieldPoint (const vtkm::cont::DataSet &inDataSet, const std::string &resultFieldName, const vtkm::cont::UnknownArrayHandle &resultFieldArray) const
	Create the output data set for `DoExecute` More...

vtkm::cont::DataSet	CreateResultFieldCell (const vtkm::cont::DataSet &inDataSet, const std::string &resultFieldName, const vtkm::cont::UnknownArrayHandle &resultFieldArray) const
	Create the output data set for `DoExecute` More...

vtkm::cont::PartitionedDataSet	CreateResult (const vtkm::cont::PartitionedDataSet &input, const vtkm::cont::PartitionedDataSet &resultPartitions) const
	Create the output data set for `DoExecute`. More...

template<typename FieldMapper >
vtkm::cont::PartitionedDataSet	CreateResult (const vtkm::cont::PartitionedDataSet &input, const vtkm::cont::PartitionedDataSet &resultPartitions, FieldMapper &&fieldMapper) const
	Create the output data set for `DoExecute`. More...

template<typename FieldMapper >
vtkm::cont::DataSet	CreateResult (const vtkm::cont::DataSet &inDataSet, const vtkm::cont::UnknownCellSet &resultCellSet, FieldMapper &&fieldMapper) const
	Create the output data set for `DoExecute`. More...

template<typename FieldMapper >
vtkm::cont::DataSet	CreateResultCoordinateSystem (const vtkm::cont::DataSet &inDataSet, const vtkm::cont::UnknownCellSet &resultCellSet, const vtkm::cont::CoordinateSystem &resultCoordSystem, FieldMapper &&fieldMapper) const
	Create the output data set for `DoExecute`. More...

template<typename FieldMapper >
vtkm::cont::DataSet	CreateResultCoordinateSystem (const vtkm::cont::DataSet &inDataSet, const vtkm::cont::UnknownCellSet &resultCellSet, const std::string &coordsName, const vtkm::cont::UnknownArrayHandle &coordsData, FieldMapper &&fieldMapper) const
	Create the output data set for `DoExecute`. More...

const vtkm::cont::Field &	GetFieldFromDataSet (const vtkm::cont::DataSet &input) const
	Retrieve an input field from a `vtkm::cont::DataSet` object. More...

const vtkm::cont::Field &	GetFieldFromDataSet (vtkm::IdComponent index, const vtkm::cont::DataSet &input) const
	Retrieve an input field from a `vtkm::cont::DataSet` object. More...

virtual vtkm::cont::PartitionedDataSet	DoExecutePartitions (const vtkm::cont::PartitionedDataSet &inData)

template<typename Functor , typename... Args>
void	CastAndCallScalarField (const vtkm::cont::UnknownArrayHandle &fieldArray, Functor &&functor, Args &&... args) const
	Convenience method to get the array from a filter's input scalar field. More...

template<typename Functor , typename... Args>
void	CastAndCallScalarField (const vtkm::cont::Field &field, Functor &&functor, Args &&... args) const
	Convenience method to get the array from a filter's input scalar field. More...

template<vtkm::IdComponent VecSize, typename Functor , typename... Args>
void	CastAndCallVecField (const vtkm::cont::UnknownArrayHandle &fieldArray, Functor &&functor, Args &&... args) const
	Convenience method to get the array from a filter's input vector field. More...

template<vtkm::IdComponent VecSize, typename Functor , typename... Args>
void	CastAndCallVecField (const vtkm::cont::Field &field, Functor &&functor, Args &&... args) const
	Convenience method to get the array from a filter's input vector field. More...

template<typename Functor , typename... Args>
void	CastAndCallVariableVecField (const vtkm::cont::UnknownArrayHandle &fieldArray, Functor &&functor, Args &&... args) const
	This method is like `CastAndCallVecField` except that it can be used for a field of unknown vector size (or scalars). More...

template<typename Functor , typename... Args>
void	CastAndCallVariableVecField (const vtkm::cont::Field &field, Functor &&functor, Args &&... args) const
	This method is like `CastAndCallVecField` except that it can be used for a field of unknown vector size (or scalars). More...

Protected Attributes inherited from vtkm::filter::Filter
vtkm::cont::Invoker	Invoke

Detailed Description

Compute the finite time Lyapunov exponent (FTLE) of a vector field.

The FTLE is computed by advecting particles throughout the vector field and analyizing where they diverge or converge. By default, the points of the input vtkm::cont::DataSet are all advected for this computation unless an auxiliary grid is established.

Member Function Documentation

◆ CanThread()

bool vtkm::filter::flow::LagrangianStructures::CanThread ( ) const

inlineoverridevirtual

Returns whether the filter can execute on partitions in concurrent threads.

If a derived class's implementation of DoExecute cannot run on multiple threads, then the derived class should override this method to return false.

Reimplemented from vtkm::filter::Filter.

◆ DoExecute()

vtkm::cont::DataSet vtkm::filter::flow::LagrangianStructures::DoExecute ( const vtkm::cont::DataSet & inData )

overrideprivatevirtual

Implements vtkm::filter::Filter.

◆ GetAdvectionTime()

vtkm::FloatDefault vtkm::filter::flow::LagrangianStructures::GetAdvectionTime ( )

inline

Specify the time interval for the advection.

The FTLE works by advecting all points a finite distance, and this parameter specifies how far to advect.

◆ GetAuxiliaryGridDimensions()

vtkm::Id3 vtkm::filter::flow::LagrangianStructures::GetAuxiliaryGridDimensions ( )

inline

Specify the dimensions of the auxiliary grid for FTLE calculation.

Seeds for advection will be placed along the points of this auxiliary grid. This option has no effect unless the UseAuxiliaryGrid option is on.

◆ GetFlowMapOutput()

vtkm::cont::ArrayHandle<vtkm::Vec3f> vtkm::filter::flow::LagrangianStructures::GetFlowMapOutput ( )

inline

Specify the array representing the flow map output to be used for FTLE calculation.

◆ GetNumberOfSteps()

vtkm::Id vtkm::filter::flow::LagrangianStructures::GetNumberOfSteps ( )

inline

Specify the maximum number of steps each particle is allowed to traverse.

This can limit the total length of displacements used when computing the FTLE.

◆ GetOutputFieldName()

std::string vtkm::filter::flow::LagrangianStructures::GetOutputFieldName ( )

inline

Specify the name of the output field in the data set returned.

By default, the field will be named FTLE.

◆ GetStepSize()

vtkm::FloatDefault vtkm::filter::flow::LagrangianStructures::GetStepSize ( )

inline

Specifies the step size used for the numerical integrator.

The numerical integrators operate by advancing each particle by a finite amount. This parameter defines the distance to advance each time. Smaller values are more accurate but take longer to integrate. An appropriate step size is usually around the size of each cell.

◆ GetUseAuxiliaryGrid()

bool vtkm::filter::flow::LagrangianStructures::GetUseAuxiliaryGrid ( )

inline

Specify whether to use an auxiliary grid.

When this flag is off (the default), then the points of the mesh representing the vector field are advected and used for computing the FTLE. However, if the mesh is too coarse, the FTLE will likely be inaccurate. Or if the mesh is unstructured the FTLE may be less efficient to compute. When this flag is on, an auxiliary grid of uniformly spaced points is used for the FTLE computation.

◆ GetUseFlowMapOutput()

bool vtkm::filter::flow::LagrangianStructures::GetUseFlowMapOutput ( )

inline

Specify whether to use flow maps instead of advection.

If the start and end points for FTLE calculation are known already, advection is an unnecessary step. This flag allows users to bypass advection, and instead use a precalculated flow map. By default this option is off.

◆ SetAdvectionTime()

void vtkm::filter::flow::LagrangianStructures::SetAdvectionTime ( vtkm::FloatDefault advectionTime )

inline

Specify the time interval for the advection.

The FTLE works by advecting all points a finite distance, and this parameter specifies how far to advect.

◆ SetAuxiliaryGridDimensions()

void vtkm::filter::flow::LagrangianStructures::SetAuxiliaryGridDimensions ( vtkm::Id3 auxiliaryDims )

inline

Specify the dimensions of the auxiliary grid for FTLE calculation.

Seeds for advection will be placed along the points of this auxiliary grid. This option has no effect unless the UseAuxiliaryGrid option is on.

◆ SetFlowMapOutput()

void vtkm::filter::flow::LagrangianStructures::SetFlowMapOutput ( vtkm::cont::ArrayHandle< vtkm::Vec3f > & flowMap )

inline

Specify the array representing the flow map output to be used for FTLE calculation.

◆ SetNumberOfSteps()

void vtkm::filter::flow::LagrangianStructures::SetNumberOfSteps ( vtkm::Id n )

inline

Specify the maximum number of steps each particle is allowed to traverse.

This can limit the total length of displacements used when computing the FTLE.

◆ SetOutputFieldName()

void vtkm::filter::flow::LagrangianStructures::SetOutputFieldName ( std::string outputFieldName )

inline

Specify the name of the output field in the data set returned.

By default, the field will be named FTLE.

◆ SetStepSize()

void vtkm::filter::flow::LagrangianStructures::SetStepSize ( vtkm::FloatDefault s )

inline

Specifies the step size used for the numerical integrator.

The numerical integrators operate by advancing each particle by a finite amount. This parameter defines the distance to advance each time. Smaller values are more accurate but take longer to integrate. An appropriate step size is usually around the size of each cell.

◆ SetUseAuxiliaryGrid()

void vtkm::filter::flow::LagrangianStructures::SetUseAuxiliaryGrid ( bool useAuxiliaryGrid )

inline

Specify whether to use an auxiliary grid.

When this flag is off (the default), then the points of the mesh representing the vector field are advected and used for computing the FTLE. However, if the mesh is too coarse, the FTLE will likely be inaccurate. Or if the mesh is unstructured the FTLE may be less efficient to compute. When this flag is on, an auxiliary grid of uniformly spaced points is used for the FTLE computation.

◆ SetUseFlowMapOutput()

void vtkm::filter::flow::LagrangianStructures::SetUseFlowMapOutput ( bool useFlowMapOutput )

inline

Specify whether to use flow maps instead of advection.

If the start and end points for FTLE calculation are known already, advection is an unnecessary step. This flag allows users to bypass advection, and instead use a precalculated flow map. By default this option is off.

Member Data Documentation

◆ AdvectionTime

vtkm::FloatDefault vtkm::filter::flow::LagrangianStructures::AdvectionTime

private

◆ AuxiliaryDims

vtkm::Id3 vtkm::filter::flow::LagrangianStructures::AuxiliaryDims

private

◆ FlowMapOutput

vtkm::cont::ArrayHandle<vtkm::Vec3f> vtkm::filter::flow::LagrangianStructures::FlowMapOutput

private

◆ NumberOfSteps

vtkm::Id vtkm::filter::flow::LagrangianStructures::NumberOfSteps = 0

private

◆ OutputFieldName

std::string vtkm::filter::flow::LagrangianStructures::OutputFieldName = "FTLE"

private

◆ StepSize

vtkm::FloatDefault vtkm::filter::flow::LagrangianStructures::StepSize = 1.0f

private

◆ UseAuxiliaryGrid

bool vtkm::filter::flow::LagrangianStructures::UseAuxiliaryGrid = false

private

◆ UseFlowMapOutput

bool vtkm::filter::flow::LagrangianStructures::UseFlowMapOutput = false

private

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

LagrangianStructures.h

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ CanThread()

◆ DoExecute()

◆ GetAdvectionTime()

◆ GetAuxiliaryGridDimensions()

◆ GetFlowMapOutput()

◆ GetNumberOfSteps()

◆ GetOutputFieldName()

◆ GetStepSize()

◆ GetUseAuxiliaryGrid()

◆ GetUseFlowMapOutput()

◆ SetAdvectionTime()

◆ SetAuxiliaryGridDimensions()

◆ SetFlowMapOutput()

◆ SetNumberOfSteps()

◆ SetOutputFieldName()

◆ SetStepSize()

◆ SetUseAuxiliaryGrid()

◆ SetUseFlowMapOutput()

Member Data Documentation

◆ AdvectionTime

◆ AuxiliaryDims

◆ FlowMapOutput

◆ NumberOfSteps

◆ OutputFieldName

◆ StepSize

◆ UseAuxiliaryGrid

◆ UseFlowMapOutput