CGAL::Alpha_status< NT > Class Template Reference

#include <CGAL/Alpha_shape_cell_base_3.h>

Definition

The class Alpha_status is a small data structure to store the critical alpha values of faces of an alpha shape.

Each face has three critical alpha values, called alpha_min, alpha_mid and alpha_max in increasing order. The face will be exterior for any \( \alpha < \) alpha_min, singular for alpha_min \( \leq \alpha < \) alpha_mid, regular for alpha_mid \( \leq \alpha < \) alpha_max and interior for alpha_max \( \leq \alpha\). The value alpha_min is undefined for faces which are not Gabriel faces and therefore do not appear in the alpha complex without any of their including face. The value alpha_max is undefined for convex hull faces which can never be interior. The data structure also includes two Boolean to mark if the face is a Gabriel face or a convex hull face.

The class Alpha_status is parameterized by a number type NT.

See Also

AlphaShapeCell_3

AlphaShapeVertex_3

Creation
	Alpha_status ()
	default constructor. More...

Modifiers
void	set_is_Gabriel (bool yesorno)
	sets Gabriel marker. More...
void	set_is_on_chull (bool yesorno)
	sets convex hull marker. More...
void	set_alpha_min (NT alpha)
	sets alpha_min. More...
void	set_alpha_mid (NT alpha)
	sets alpha_mid. More...
void	set_alpha_max (NT alpha)
	sets alpha_max. More...

Access Functions
bool	is_Gabriel () const
	Returns true for Gabriel faces. More...
bool	is_on_chull () const
	Returns true for convex hull faces. More...
NT	alpha_min () const
	Returns the alpha_min. More...
NT	alpha_mid () const
	Returns the alpha_mid. More...
NT	alpha_max () const
	Returns alpha_max. More...

Constructor & Destructor Documentation

template<typename NT >

CGAL::Alpha_status< NT >::Alpha_status

(

)

default constructor.

Member Function Documentation

template<typename NT >

NT CGAL::Alpha_status< NT >::alpha_max

(

)

const

Returns alpha_max.

Precondition

is_on_chull() returns false.

template<typename NT >

NT CGAL::Alpha_status< NT >::alpha_mid

(

)

const

Returns the alpha_mid.

template<typename NT >

NT CGAL::Alpha_status< NT >::alpha_min

(

)

const

Returns the alpha_min.

Precondition

is_Gabriel() returns false;

template<typename NT >

bool CGAL::Alpha_status< NT >::is_Gabriel

(

)

const

Returns true for Gabriel faces.

template<typename NT >

bool CGAL::Alpha_status< NT >::is_on_chull

(

)

const

Returns true for convex hull faces.

template<typename NT >

void CGAL::Alpha_status< NT >::set_alpha_max

(

NT

alpha

)

sets alpha_max.

template<typename NT >

void CGAL::Alpha_status< NT >::set_alpha_mid

(

NT

alpha

)

sets alpha_mid.

template<typename NT >

void CGAL::Alpha_status< NT >::set_alpha_min

(

NT

alpha

)

sets alpha_min.

template<typename NT >

void CGAL::Alpha_status< NT >::set_is_Gabriel

(

bool

yesorno

)

sets Gabriel marker.

template<typename NT >

void CGAL::Alpha_status< NT >::set_is_on_chull

(

bool

yesorno

)

sets convex hull marker.