RandomPolygonTraits_2 Concept Reference

Definition

The concept RandomPolygonTraits_2 describes the requirements for the traits class used by the function random_polygon_2().

Has models

All models of the concept Kernel

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	Orientation_2
	Predicate object type that determines the orientation of three points.
typedef unspecified_type	Less_xy_2
	Binary predicate object type comparing Point_2s lexicographically.

Operations
Less_xy_2	less_xy_2_object ()
Orienation_2	orientation_2_object ()

Member Typedef Documentation

Less_xy_2

typedef unspecified_type RandomPolygonTraits_2::Less_xy_2

Binary predicate object type comparing Point_2s lexicographically.

It must provide bool operator()(Point_2 p, Point_2 q) that returns true iff $p <_{xy} q$. We have $p<_{xy}q$, iff $p_x < q_x$ or $p_x = q_x$ and $p_y < q_y$, where $p_x$ and $p_y$ denote the $x$ and $y$ coordinates of point $p$, resp.

Orientation_2

typedef unspecified_type RandomPolygonTraits_2::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 $l$.