CGAL::Classification::Local_eigen_analysis Class Reference

#include <CGAL/Classification/Local_eigen_analysis.h>

Definition

Class that precomputes and stores the eigenvectors and eigenvalues of the covariance matrices of all points of a point set using a local neighborhood.

This class can be used to compute eigen features (see Predefined Features) and to estimate local normal vectors and tangent planes.

Public Types
typedef CGAL::cpp11::array< float, 3 >	Eigenvalues
	Eigenvalues (sorted in ascending order)

Public Member Functions
template<typename PointRange , typename PointMap , typename NeighborQuery , typename ConcurrencyTag , typename DiagonalizeTraits >
	Local_eigen_analysis (const PointRange &input, PointMap point_map, const NeighborQuery &neighbor_query, const ConcurrencyTag &=ConcurrencyTag(), const DiagonalizeTraits &=DiagonalizeTraits())
	Computes the local eigen analysis of an input range based on a local neighborhood. More...
template<typename GeomTraits >
GeomTraits::Vector_3	normal_vector (std::size_t index) const
	Returns the estimated unoriented normal vector of the point at position index. More...
template<typename GeomTraits >
GeomTraits::Plane_3	plane (std::size_t index) const
	Returns the estimated local tangent plane of the point at position index. More...
const Eigenvalues &	eigenvalue (std::size_t index) const
	Returns the normalized eigenvalues of the point at position index.
float	sum_of_eigenvalues (std::size_t index) const
	Returns the sum of eigenvalues of the point at position index.

Constructor & Destructor Documentation

Local_eigen_analysis()

template<typename PointRange , typename PointMap , typename NeighborQuery , typename ConcurrencyTag , typename DiagonalizeTraits >

CGAL::Classification::Local_eigen_analysis::Local_eigen_analysis	(	const PointRange &	input,
		PointMap	point_map,
		const NeighborQuery &	neighbor_query,
		const ConcurrencyTag &	= ConcurrencyTag(),
		const DiagonalizeTraits &	= DiagonalizeTraits()
	)

Computes the local eigen analysis of an input range based on a local neighborhood.

Template Parameters

PointRange	model of ConstRange. Its iterator type is RandomAccessIterator and its value type is the key type of PointMap.
PointMap	model of ReadablePropertyMap whose key type is the value type of the iterator of PointRange and value type is CGAL::Point_3.
NeighborQuery	model of NeighborQuery
ConcurrencyTag	enables sequential versus parallel algorithm. Possible values are Parallel_tag (default value is CGAL is linked with TBB) or Sequential_tag (default value otherwise).
DiagonalizeTraits	model of DiagonalizeTraits used for matrix diagonalization. It can be omitted: if Eigen 3 (or greater) is available and CGAL_EIGEN3_ENABLED is defined then an overload using Eigen_diagonalize_traits is provided. Otherwise, the internal implementation Diagonalize_traits is used.

Parameters

input	point range.
point_map	property map to access the input points.
neighbor_query	object used to access neighborhoods of points.

Member Function Documentation

normal_vector()

template<typename GeomTraits >

GeomTraits::Vector_3 CGAL::Classification::Local_eigen_analysis::normal_vector

(

std::size_t

index

)

const

Returns the estimated unoriented normal vector of the point at position index.

Template Parameters

GeomTraits

model of CGAL Kernel.

plane()

template<typename GeomTraits >

GeomTraits::Plane_3 CGAL::Classification::Local_eigen_analysis::plane

(

std::size_t

index

)

const

Returns the estimated local tangent plane of the point at position index.

Template Parameters

GeomTraits

model of CGAL Kernel.