#include <nrt/PointCloud2/Search/Search.H>

A class for searching point clouds.

Provides functionality to search through a point cloud based upon an approximate KDTree implementation powered by FLANN.

Examples:: tests/test-PointCloud2Search.C.

Definition at line 51 of file Search.H.

Inheritance diagram for nrt::Search:

Public Types
typedef PointCloud2::Geometry	Geometry

typedef PointCloud2::BaseType	BaseType

Public Member Functions
	Search (double epsilon=0.0)
	Create an empty search. More...

	Search (PointCloud2 const input, double epsilon=0.0)
	Create a new search based upon a point cloud. More...

	Search (PointCloud2 const input, Indices const indices, double epsilon=0.0)
	Create a new search based upon a point cloud subset. More...

std::vector< std::pair< size_t, BaseType > >	knn (Geometry const &query, int k)
	Perform a k-nearest neighbor search on the geometry. More...

template<class Field >
std::vector< std::pair< size_t, BaseType > >	knn (Field const &query, int k)
	Perform a k-nearest neighbor search on a specific field. More...

template<class Field , class Distance >
std::vector< std::pair< size_t, BaseType > >	knn (Field const &query, int k, Distance const &dist)
	Perform a k-nearest neighbor search on a specific field using a non-standard Distance functor. More...

std::vector< std::pair< size_t, BaseType > >	radius (Geometry const &query, double const radius, size_t maxResults=0, bool sort=false)
	Perform a fixed radius search on the geometry. More...

template<class Field >
std::vector< std::pair< size_t, BaseType > >	radius (Field const &query, double const radius, size_t maxResults=0, bool sort=false)
	Perform a fixed radius search on a specific field. More...

void	rebuild (PointCloud2 const cloud)
	Forces a rebuild on the next search to match an updated point cloud. More...

void	rebuild (PointCloud2 const cloud, Indices const indices)
	Forces a rebuild on the next search to match an updated point cloud. More...

template<class Field >
auto	knn (Field const &query, int k) -> std::vector< std::pair< size_t, BaseType >>

template<class Field , class Distance >
auto	knn (Field const &query, int k, Distance const &dist) -> std::vector< std::pair< size_t, BaseType >>

template<class Field , class Distance >
auto	knnImpl (Field const &query, int k, Distance const &dist, std::unique_ptr< flann::Index< Distance >> &indexPtr) -> std::vector< std::pair< size_t, BaseType >>

template<class Field >
auto	radius (Field const &query, double const radius, size_t maxResults, bool sort) -> std::vector< std::pair< size_t, BaseType >>

Public Member Functions inherited from nrt::SourceCloud
	SourceCloud ()
	Initializes with no data.

	SourceCloud (PointCloud2 const cloud)
	Initializes with a point cloud and no subset.

	SourceCloud (PointCloud2 const cloud, Indices const indices)
	Initializes with a point cloud and a specific subset.

size_t	getWorkingSize () const
	Returns the current working size of the Source. More...

Static Public Member Functions
static Indices	extractIndices (std::vector< std::pair< size_t, BaseType >> const &results)
	Convenience function to extract the results of a search as a set of indices.

Protected Member Functions
template<class Field , class Distance >
std::vector< std::pair< size_t, BaseType > >	knnImpl (Field const &query, int k, Distance const &dist, std::unique_ptr< flann::Index< Distance >> &indexPtr)
	Does the actual work for a specific field knn search. More...

bool	rebuildFLANNIndex ()
	Rebuilds FLANN index if necessary. More...

template<class Field >
bool	rebuildFLANNIndex ()
	Rebuilds FLANN index if necessary. More...

template<class Field , class Distance >
bool	rebuildFLANNIndex (Distance const &dist, std::unique_ptr< flann::Index< Distance >> &indexPtr)
	Rebuilds FLANN index if necessary. More...

Protected Member Functions inherited from nrt::SourceCloud
void	setCloud (PointCloud2 const cloud)
	Sets to use a specific cloud.

void	setCloud (PointCloud2 const cloud, Indices const indices)
	Sets to sue a specific subset of a cloud.

Additional Inherited Members
Public Attributes inherited from nrt::SourceCloud
PointCloud2	cloud
	The source point cloud.

Indices	indices
	The optional indices.

bool	useSubset
	Whether we use a subset or not.

Constructor & Destructor Documentation

nrt::Search::Search ( double epsilon = 0.0)

Create an empty search.

For this search to work, you will need to explicitly call rebuild before performing a search.

Parameters

epsilon The minimum required accuracy of the search

nrt::Search::Search	(	PointCloud2 const	input,
		double	epsilon = `0.0`
	)

Create a new search based upon a point cloud.

The cloud will be indexed as soon as the first search is conducted. If the search type changes, the index will be rebuilt to the latest search field type

Parameters

input	The point cloud to search
epsilon	The minimum required accuracy of the search

nrt::Search::Search	(	PointCloud2 const	input,
		Indices const	indices,
		double	epsilon = `0.0`
	)

Create a new search based upon a point cloud subset.

The cloud will be indexed as soon as the first search is conducted. If the search type changes, the index will be rebuilt to the latest search field type

Parameters

input	The point cloud to search
indices	The subset of the cloud to search through
epsilon	The minimum required accuracy of the search

Member Function Documentation

std::vector<std::pair<size_t, BaseType> > nrt::Search::knn	(	Geometry const &	query,
		int	k
	)

Perform a k-nearest neighbor search on the geometry.

Will rebuild the search index if the previous search type was not geometry.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Parameters

query	The geometrical query
k	The maximum number of neighbors to find

Returns: The indices of the neighbors and their squared distances

Examples:: tests/test-PointCloud2Search.C.

Referenced by nrt::CorrespondenceEstimationNearestNeighbor::findReciprocalCorrespondence().

template<class Field >

std::vector<std::pair<size_t, BaseType> > nrt::Search::knn	(	Field const &	query,
		int	k
	)

Perform a k-nearest neighbor search on a specific field.

Will rebuild the search index if the previous search type was not Field.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Parameters

query	The specific field query
k	The maximum number of neighbors to find

Returns: The indices of the neighbors and their squared distances

template<class Field , class Distance >

std::vector<std::pair<size_t, BaseType> > nrt::Search::knn	(	Field const &	query,
		int	k,
		Distance const &	dist
	)

Perform a k-nearest neighbor search on a specific field using a non-standard Distance functor.

Will rebuild the search index if the previous search type was not Field or the distance functor changed.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Note: This function is not thread safe

Todo:: revisit and make thread safe

Template Parameters

Field	The field to query. Can be the geometry as well.
Distance	The distance functor type

Parameters

query	The specific field query
k	The maximum number of neighbors to find
dist	The distance functor (see flann documentation for examples)

Returns: The indices of the neighbors and their squared distances

std::vector<std::pair<size_t, BaseType> > nrt::Search::radius	(	Geometry const &	query,
		double const	radius,
		size_t	maxResults = `0`,
		bool	sort = `false`
	)

Perform a fixed radius search on the geometry.

Will rebuild the search index if the previous search type was not geometry.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Parameters

query	The geometrical query
radius	The radius within query to find neighbors
maxResults	The maximum number of neighbors to find. Zero or > cloud size to return maximum.
sort	Whether to sort results by distance (will slow down computation)

Returns: The indices of the neighbors and their squared distances

Examples:: tests/test-PointCloud2Search.C.

template<class Field >

std::vector<std::pair<size_t, BaseType> > nrt::Search::radius	(	Field const &	query,
		double const	radius,
		size_t	maxResults = `0`,
		bool	sort = `false`
	)

Perform a fixed radius search on a specific field.

Will rebuild the search index if the previous search type was not Field.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Parameters

query	The specific field query
radius	The radius within query to find neighbors
maxResults	The maximum number of neighbors to find. Zero or > cloud size to return maximum.
sort	Whether to sort results by distance (will slow down computation)

Returns: The indices of the neighbors and their squared distances

void nrt::Search::rebuild ( PointCloud2 const cloud)

Forces a rebuild on the next search to match an updated point cloud.

Since the cloud we reference may be changed externally, which would cause the external cloud to create its own copy of the data, it may be necessary to update the cloud that search is referencing

Examples:: tests/test-PointCloud2Search.C.

void nrt::Search::rebuild	(	PointCloud2 const	cloud,
		Indices const	indices
	)

Forces a rebuild on the next search to match an updated point cloud.

Since the cloud we reference may be changed externally, which would cause the external cloud to create its own copy of the data, it may be necessary to update the cloud that search is referencing

template<class Field , class Distance >

std::vector<std::pair<size_t, BaseType> > nrt::Search::knnImpl	(	Field const &	query,
		int	k,
		Distance const &	dist,
		std::unique_ptr< flann::Index< Distance >> &	indexPtr
	)

protected

Does the actual work for a specific field knn search.

Will rebuild the search index if the previous search type was not Field or the distance functor changed.

If this search is operating upon a subset, the returned indices will refer to the original cloud and not the subset (e.g. instead of 0 referring to the first subset index, it will refer to the real index of whatever subset[0] represents).

Template Parameters

Field	The field to query. Can be the geometry as well.
Distance	The distance functor type

Parameters

query	The specific field query
k	The maximum number of neighbors to find
dist	The distance functor (see flann documentation for examples)
indexPtr	a unique_ptr that is the sole owner of the FLANN index to use

Returns: The indices of the neighbors and their squared distances

bool nrt::Search::rebuildFLANNIndex ( )

inlineprotected

Rebuilds FLANN index if necessary.

Returns: true if the flann index is valid

Definition at line 176 of file SearchImpl.H.

template<class Field >

bool nrt::Search::rebuildFLANNIndex ( )

protected

Rebuilds FLANN index if necessary.

Returns: true if the flann index is valid

template<class Field , class Distance >

bool nrt::Search::rebuildFLANNIndex	(	Distance const &	dist,
		std::unique_ptr< flann::Index< Distance >> &	indexPtr
	)

inlineprotected

Rebuilds FLANN index if necessary.

Returns: true if the flann index is valid

Definition at line 182 of file SearchImpl.H.

References nrt::SourceCloud::cloud, nrt::SourceCloud::indices, and nrt::SourceCloud::useSubset.

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

include/nrt/PointCloud2/Search/Search.H
include/nrt/PointCloud2/Search/details/SearchImpl.H

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

Member Function Documentation