Point Set Shape Detection Reference

Sven Oesau, Yannick Verdie, Clément Jamin, Pierre Alliez

This component implements an efficient RANSAC-based primitive shape detection algorithm for point sets with unoriented normals. Five types of primitive shapes are detected: plane, sphere, cylinder, cone and torus. Other types of shapes can be detected through implementing a class deriving from the base shape class.

Introduced in: CGAL 4.7
BibTeX: cgal:ovja-pssd-18b
License: GPL
Windows Demo: Polyhedron demo
Common Demo Dlls: dlls

Classified Reference Pages

Concept

• EfficientRANSACTraits

Main Classes

• CGAL::Shape_detection_3::Efficient_RANSAC<Traits>
• CGAL::Shape_detection_3::Efficient_RANSAC_traits

Shape Interface

• CGAL::Shape_detection_3::Shape_base<Traits>

Shape Classes

• CGAL::Shape_detection_3::Plane<Traits>
• CGAL::Shape_detection_3::Sphere<Traits>
• CGAL::Shape_detection_3::Cylinder<Traits>
• CGAL::Shape_detection_3::Cone<Traits>
• CGAL::Shape_detection_3::Torus<Traits>

Functions

• CGAL::regularize_planes()

Modules
	Concepts
	Shapes

Files
file	Shape_detection_3.h
	Convenience header file including the headers of this package.
file	regularize_planes.h

Classes
class	CGAL::Shape_detection_3::Efficient_RANSAC< Traits >
	A shape detection algorithm using a RANSAC method. More...
struct	CGAL::Shape_detection_3::Efficient_RANSAC_traits< Gt, InputRange, InputPointMap, InputNormalMap >
	Default traits class to use the shape detection class Efficient_RANSAC. More...

Functions
template<typename EfficientRANSACTraits >
void	CGAL::regularize_planes (const Shape_detection_3::Efficient_RANSAC< EfficientRANSACTraits > &shape_detection, bool regularize_parallelism, bool regularize_orthogonality, bool regularize_coplanarity, bool regularize_axis_symmetry, typename EfficientRANSACTraits::FT tolerance_angle=(typename EfficientRANSACTraits::FT) 25.0, typename EfficientRANSACTraits::FT tolerance_coplanarity=(typename EfficientRANSACTraits::FT) 0.01, typename EfficientRANSACTraits::Vector_3 symmetry_direction=typename EfficientRANSACTraits::Vector_3((typename EfficientRANSACTraits::FT) 0.,(typename EfficientRANSACTraits::FT) 0.,(typename EfficientRANSACTraits::FT) 1.))
	Given a set of detected planes with their respective inlier sets, this function enables to regularize the planes: More...

Function Documentation

template<typename EfficientRANSACTraits >

void CGAL::regularize_planes	(	const Shape_detection_3::Efficient_RANSAC< EfficientRANSACTraits > &	shape_detection,
		bool	regularize_parallelism,
		bool	regularize_orthogonality,
		bool	regularize_coplanarity,
		bool	regularize_axis_symmetry,
		typename EfficientRANSACTraits::FT	tolerance_angle = (typename EfficientRANSACTraits::FT)25.0,
		typename EfficientRANSACTraits::FT	tolerance_coplanarity = (typename EfficientRANSACTraits::FT)0.01,
		typename EfficientRANSACTraits::Vector_3	symmetry_direction = typename EfficientRANSACTraits::Vector_3 ((typename EfficientRANSACTraits::FT)0.,                         (typename EfficientRANSACTraits::FT)0.,                         (typename EfficientRANSACTraits::FT)1.)
	)

Given a set of detected planes with their respective inlier sets, this function enables to regularize the planes:

• Planes near parallel can be made exactly parallel.
• Planes near orthogonal can be made exactly orthogonal.
• Planes parallel and near coplanar can be made exactly coplanar.
• Planes near symmetrical with a user-defined axis can be made exactly symmetrical.

Planes are directly modified. Points are left unaltered, as well as their relationships to planes (no transfer of point from a primitive plane to another).

The implementation follows [2].

Template Parameters

Traits

a model of EfficientRANSACTraits

Parameters

shape_detection

Shape detection object used to detect shapes from the input data. While the shape detection algorithm deals with several types of primitive shapes only planes can be regularized.

Warning

The shape_detection parameter must have already detected shapes. If no plane exists in it, the regularization function doesn't do anything.

Parameters

regularize_parallelism	Select whether parallelism is regularized or not.
regularize_orthogonality	Select whether orthogonality is regularized or not.
regularize_coplanarity	Select whether coplanarity is regularized or not.
regularize_axis_symmetry	Select whether axis symmetry is regularized or not.
tolerance_angle	Tolerance of deviation between normal vectors of planes (in degrees) used for parallelism, orthogonality and axis symmetry. Default value is 25 degrees.
tolerance_coplanarity	Maximal distance between two parallel planes such that they are considered coplanar. Default value is 0.01.
symmetry_direction	Chosen axis for symmetry regularization. Default value is the Z axis.

#include <CGAL/regularize_planes.h>

Examples:

Point_set_shape_detection_3/plane_regularization.cpp.