Filtering (e.g. diffusion) of narrow-band level sets. An optional scalar field can be used to produce a (smooth) alpha mask for the filtering. More...

#include <openvdb/tools/LevelSetFilter.h>

Inherits LevelSetTracker< GridT, InterruptT >.

Public Types
using	BaseType = LevelSetTracker< GridT, InterruptT >

using	GridType = GridT

using	MaskType = MaskT

using	TreeType = typename GridType::TreeType

using	ValueType = typename TreeType::ValueType

using	AlphaType = typename MaskType::ValueType

using	TrimMode = lstrack::TrimMode

using	LeafType = typename TreeType::LeafNodeType

using	LeafManagerType = typename tree::LeafManager< TreeType >

using	LeafRange = typename LeafManagerType::LeafRange

using	BufferType = typename LeafManagerType::BufferType

using	MaskTreeType = typename TreeType::template ValueConverter< ValueMask >::Type

Public Member Functions
	LevelSetFilter (GridType &grid, InterruptT *interrupt=nullptr)
	Main constructor from a grid. More...

	~LevelSetFilter () override
	Default destructor. More...

AlphaType	minMask () const
	Return the minimum value of the mask to be used for the derivation of a smooth alpha value. More...

AlphaType	maxMask () const
	Return the maximum value of the mask to be used for the derivation of a smooth alpha value. More...

void	setMaskRange (AlphaType min, AlphaType max)
	Define the range for the (optional) scalar mask. More...

bool	isMaskInverted () const
	Return true if the mask is inverted, i.e. min->max in the original mask maps to 1->0 in the inverted alpha mask. More...

void	invertMask (bool invert=true)
	Invert the optional mask, i.e. min->max in the original mask maps to 1->0 in the inverted alpha mask. More...

void	meanCurvature (const MaskType *mask=nullptr)
	One iteration of mean-curvature flow of the level set. More...

void	laplacian (const MaskType *mask=nullptr)
	One iteration of Laplacian flow of the level set. More...

void	gaussian (int width=1, const MaskType *mask=nullptr)
	One iteration of a fast separable Gaussian filter. More...

void	offset (ValueType offset, const MaskType *mask=nullptr)
	Offset the level set by the specified (world) distance. More...

void	median (int width=1, const MaskType *mask=nullptr)
	One iteration of median-value flow of the level set. More...

void	mean (int width=1, const MaskType *mask=nullptr)
	One iteration of mean-value flow of the level set. More...

template<typename MaskType >
void	normalize (const MaskType *mask)
	Iterative normalization, i.e. solving the Eikonal equation. More...

void	normalize ()
	Iterative normalization, i.e. solving the Eikonal equation. More...

template<typename MaskT >
void	normalize (const MaskT *mask)

void	track ()
	Track the level set interface, i.e. rebuild and normalize the narrow band of the level set. More...

void	prune ()
	Set voxels that are outside the narrow band to the background value (if trimming is enabled) and prune the grid. More...

void	dilate (int iterations=1)
	Fast but approximate dilation of the narrow band - one layer at a time. Normally we recommend using the resize method below which internally calls dilate (or erode) with the correct number of iterations to achieve the desired half voxel width of the narrow band (3 is recommended for most level set applications). More...

void	erode (int iterations=1)
	Erodes the width of the narrow-band and update the background values. More...

bool	resize (Index halfWidth=static_cast< Index >(LEVEL_SET_HALF_WIDTH))
	Resize the width of the narrow band, i.e. perform dilation and renormalization or erosion as required. More...

ValueType	getHalfWidth () const
	Return the half width of the narrow band in floating-point voxel units. More...

State	getState () const
	Return the state of the tracker (see struct defined above) More...

void	setState (const State &s)
	Set the state of the tracker (see struct defined above) More...

math::BiasedGradientScheme	getSpatialScheme () const

void	setSpatialScheme (math::BiasedGradientScheme s)
	Set the spatial finite difference scheme. More...

math::TemporalIntegrationScheme	getTemporalScheme () const

void	setTemporalScheme (math::TemporalIntegrationScheme s)
	Set the spatial finite difference scheme. More...

int	getNormCount () const

void	setNormCount (int n)
	Set the number of normalizations performed per track or normalize call. More...

int	getGrainSize () const

void	setGrainSize (int grainsize)
	Set the grain-size used for multi-threading. More...

TrimMode	trimming () const
	Return the trimming mode for voxels outside the narrow band. More...

void	setTrimming (TrimMode mode)
	Specify whether to trim voxels outside the narrow band prior to pruning. More...

ValueType	voxelSize () const

void	startInterrupter (const char *msg)

void	endInterrupter ()

bool	checkInterrupter ()

const GridType &	grid () const

LeafManagerType &	leafs ()

const LeafManagerType &	leafs () const

Detailed Description

template<typename GridT, typename MaskT = typename GridT::template ValueConverter<float>::Type, typename InterruptT = util::NullInterrupter>
class openvdb::v9_0::tools::LevelSetFilter< GridT, MaskT, InterruptT >

Filtering (e.g. diffusion) of narrow-band level sets. An optional scalar field can be used to produce a (smooth) alpha mask for the filtering.

Note: This class performs proper interface tracking which allows for unrestricted surface deformations

Member Typedef Documentation

using AlphaType = typename MaskType::ValueType

using BaseType = LevelSetTracker<GridT, InterruptT>

using BufferType = typename LeafManagerType::BufferType

inherited

using GridType = GridT

using LeafManagerType = typename tree::LeafManager<TreeType>

inherited

using LeafRange = typename LeafManagerType::LeafRange

inherited

using LeafType = typename TreeType::LeafNodeType

inherited

using MaskTreeType = typename TreeType::template ValueConverter<ValueMask>::Type

inherited

using MaskType = MaskT

using TreeType = typename GridType::TreeType

using TrimMode = lstrack::TrimMode

inherited

using ValueType = typename TreeType::ValueType

Constructor & Destructor Documentation

LevelSetFilter	(	GridType &	grid,
		InterruptT *	interrupt = `nullptr`
	)

inline

Main constructor from a grid.

Parameters

grid	The level set to be filtered.
interrupt	Optional interrupter.

~LevelSetFilter ( )

inlineoverride

Default destructor.

Member Function Documentation

bool checkInterrupter ( )

inlineinherited

Returns: false if the process was interrupted

void dilate ( int iterations = 1 )

inherited

Fast but approximate dilation of the narrow band - one layer at a time. Normally we recommend using the resize method below which internally calls dilate (or erode) with the correct number of iterations to achieve the desired half voxel width of the narrow band (3 is recommended for most level set applications).

Note: Since many level set applications perform interface-tracking, which in turn rebuilds the narrow-band accurately, this dilate method can often be used with a single iterations of low-order re-normalization. This effectively allows very narrow bands to be created from points or polygons (e.g. with a half voxel width of 1), followed by a fast but approximate dilation (typically with a half voxel width of 3). This can be significantly faster than generating the final width of the narrow band from points or polygons.

void endInterrupter ( )

inlineinherited

void erode ( int iterations = 1 )

inherited

Erodes the width of the narrow-band and update the background values.

Exceptions

ValueError if iterations is larger than the current half-width.

void gaussian	(	int	width = `1`,
		const MaskType *	mask = `nullptr`
	)

inline

One iteration of a fast separable Gaussian filter.

Parameters

width	Width of the Gaussian kernel in voxel units.
mask	Optional alpha mask.

Note: This is approximated as 4 iterations of a separable mean filter which typically leads an approximation that's better than 95%!

int getGrainSize ( ) const

inlineinherited

Returns: the grain-size used for multi-threading

ValueType getHalfWidth ( ) const

inlineinherited

Return the half width of the narrow band in floating-point voxel units.

int getNormCount ( ) const

inlineinherited

Returns: The number of normalizations performed per track or normalize call.

math::BiasedGradientScheme getSpatialScheme ( ) const

inlineinherited

Returns: the spatial finite difference scheme

State getState ( ) const

inlineinherited

Return the state of the tracker (see struct defined above)

math::TemporalIntegrationScheme getTemporalScheme ( ) const

inlineinherited

Returns: the temporal integration scheme

const GridType& grid ( ) const

inlineinherited

void invertMask ( bool invert = true )

inline

Invert the optional mask, i.e. min->max in the original mask maps to 1->0 in the inverted alpha mask.

bool isMaskInverted ( ) const

inline

Return true if the mask is inverted, i.e. min->max in the original mask maps to 1->0 in the inverted alpha mask.

void laplacian ( const MaskType * mask = nullptr )

inline

One iteration of Laplacian flow of the level set.

Parameters

mask	Optional alpha mask.

LeafManagerType& leafs ( )

inlineinherited

const LeafManagerType& leafs ( ) const

inlineinherited

AlphaType maxMask ( ) const

inline

Return the maximum value of the mask to be used for the derivation of a smooth alpha value.

void mean	(	int	width = `1`,
		const MaskType *	mask = `nullptr`
	)

inline

One iteration of mean-value flow of the level set.

Parameters

width	Width of the mean-value kernel in voxel units.
mask	Optional alpha mask.

Note: This filter is separable so it's fast!

void meanCurvature ( const MaskType * mask = nullptr )

inline

One iteration of mean-curvature flow of the level set.

Parameters

mask	Optional alpha mask.

void median	(	int	width = `1`,
		const MaskType *	mask = `nullptr`
	)

inline

One iteration of median-value flow of the level set.

Parameters

width	Width of the median-value kernel in voxel units.
mask	Optional alpha mask.

Warning: This filter is not separable and is hence relatively slow!

AlphaType minMask ( ) const

inline

Return the minimum value of the mask to be used for the derivation of a smooth alpha value.

void normalize ( const MaskType * mask )

inherited

Iterative normalization, i.e. solving the Eikonal equation.

Note: The mask it optional and by default it is ignored.

void normalize ( )

inlineinherited

Iterative normalization, i.e. solving the Eikonal equation.

void normalize ( const MaskT * mask )

inherited

void offset	(	ValueType	offset,
		const MaskType *	mask = `nullptr`
	)

inline

Offset the level set by the specified (world) distance.

Parameters

offset	Value of the offset.
mask	Optional alpha mask.

void prune ( )

inherited

Set voxels that are outside the narrow band to the background value (if trimming is enabled) and prune the grid.

Pruning is done automatically as a step in tracking.

See also: setTrimming, trimming

bool resize ( Index halfWidth = static_cast<Index>(LEVEL_SET_HALF_WIDTH) )

inherited

Resize the width of the narrow band, i.e. perform dilation and renormalization or erosion as required.

void setGrainSize ( int grainsize )

inlineinherited

Set the grain-size used for multi-threading.

Note: A grainsize of 0 or less disables multi-threading!

void setMaskRange	(	AlphaType	min,
		AlphaType	max
	)

inline

Define the range for the (optional) scalar mask.

Parameters

min	Minimum value of the range.
max	Maximum value of the range.

Mask values outside the range maps to alpha values of respectfully zero and one, and values inside the range maps smoothly to 0->1 (unless of course the mask is inverted).

Exceptions

ValueError if min is not smaller than max.

void setNormCount ( int n )

inlineinherited

Set the number of normalizations performed per track or normalize call.

void setSpatialScheme ( math::BiasedGradientScheme s )

inlineinherited

Set the spatial finite difference scheme.

void setState ( const State & s )

inlineinherited

Set the state of the tracker (see struct defined above)

void setTemporalScheme ( math::TemporalIntegrationScheme s )

inlineinherited

Set the spatial finite difference scheme.

void setTrimming ( TrimMode mode )

inlineinherited

Specify whether to trim voxels outside the narrow band prior to pruning.

See also: trimming, prune

void startInterrupter ( const char * msg )

inlineinherited

void track ( )

inherited

Track the level set interface, i.e. rebuild and normalize the narrow band of the level set.

TrimMode trimming ( ) const

inlineinherited

Return the trimming mode for voxels outside the narrow band.

Trimming is enabled by default and is applied automatically prior to pruning.

See also: setTrimming, prune

ValueType voxelSize ( ) const

inlineinherited

Public Types

Public Member Functions

Detailed Description

template<typename GridT, typename MaskT = typename GridT::template ValueConverter<float>::Type, typename InterruptT = util::NullInterrupter> class openvdb::v9_0::tools::LevelSetFilter< GridT, MaskT, InterruptT >

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

template<typename GridT, typename MaskT = typename GridT::template ValueConverter<float>::Type, typename InterruptT = util::NullInterrupter>
class openvdb::v9_0::tools::LevelSetFilter< GridT, MaskT, InterruptT >