CGAL 5.5.1 - 3D Alpha Shapes
FixedAlphaShapeTraits_3 Concept Reference

## Definition

The concept FixedAlphaShapeTraits_3 describes the requirements for the geometric traits class of the underlying Delaunay triangulation of a basic alpha shape with a fixed value alpha.

Refines:

DelaunayTriangulationTraits_3, if the underlying triangulation of the alpha shape is a Delaunay triangulation.

Periodic_3DelaunayTriangulationTraits_3, if the underlying triangulation of the alpha shape is a periodic Delaunay triangulation.

Has Models:
All models of Kernel.
CGAL::Exact_predicates_inexact_constructions_kernel (recommended kernel)

## Types

typedef unspecified_type Comparison_result
CGAL::Comparison_result or Uncertain<CGAL::Comparison_result>

An object constructor able to compare the squared radius of the smallest circumscribing sphere of either four, three, two or one point(s) with a given value of alpha. More...

## Creation

FixedAlphaShapeTraits_3 ()
Default constructor.

## Member Typedef Documentation

• Comparison_result operator()(Point_3,Point_3,Point_3,Point_3)
• Comparison_result operator()(Point_3,Point_3,Point_3)
• Comparison_result operator()(Point_3,Point_3)
• Comparison_result operator()(Point_3)