CGAL 5.6 - Geometric Object Generators
RandomConvexHullTraits_2 Concept Reference

## Definition

The concept RandomConvexHullTraits_2 describes the requirements for the traits class used by the function random_convex_hull_in_disc_2().

Has Models:
CGAL kernels.

Operations

The following two member functions returning instances of the above predicate object types are required.

## Types

typedef unspecified_type FT
The coordinate type of the points of the polygon.

typedef unspecified_type Point_2
The point type of the polygon.

typedef unspecified_type Segment_2
The segment type of the polygon.

typedef unspecified_type Orientation_2
Predicate object type that determines the orientation of three points. More...

typedef unspecified_type Compare_x_2
A function object to compare the x-coordinate of two points. More...

typedef unspecified_type Compare_y_2
A function object to compare the y-coordinate of two points. More...

## Operations

Compare_x_2 compare_x_2_object ()

Compare_y_2 compare_y_2_object ()

Orientation_2 orientation_2_object ()

## ◆ Compare_x_2

A function object to compare the x-coordinate of two points.

Provides the operator:

Comparison_result operator()(Point p, Point q)

which returns SMALLER, EQUAL or LARGER according to the $$x$$-ordering of points p and q.

## ◆ Compare_y_2

A function object to compare the y-coordinate of two points.

Provides the operator:

Comparison_result operator()(Point p, Point q)

which returns (SMALLER, EQUAL or LARGER) according to the $$y$$-ordering of points p and q.

## ◆ Orientation_2

Predicate object type that determines the orientation of three points.

It must provide Orientation operator()(Point_2 p, Point_2 q, Point_2 r) that returns LEFT_TURN, if $$r$$ lies to the left of the oriented line $$l$$ defined by $$p$$ and $$q$$, returns RIGHT_TURN if $$r$$ lies to the right of $$l$$, and returns COLLINEAR if $$r$$ lies on $$l$$.