GeneralPolygonSetTraits

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GeneralPolygonSetTraits_2

Definition

This concept defines the minimal set of geometric predicates needed to perform the Boolean-set operations. It refines the directional

x-monotone arrangement-traits concept. In addition to the Point_2 and X_monotone_curve_2 types defined in the generalized concept, it defines a type that represents a general polygon and another one that represents general polygon with holes. It also requires operations that operate on these types.

Refines

ArrangementDirectionalXMonotoneTraits_2

Types

GeneralPolygonSetTraits_2::Polygon_2
	represents a general polygon. Must be a model of the GpsTraitsGeneralPolygon_2 concept.
GeneralPolygonSetTraits_2::Polygon_with_holes_2
	represents a general polygon with holes. Must be a model of the GpsTraitsGeneralPolygonWithHoles_2 concept.

GeneralPolygonSetTraits_2::Curve_const_iterator
	A const iterator of curves. Its value type is const X_monotone_curve_2.

Functor Types

GeneralPolygonSetTraits_2::Construct_polygon_2
	a functor that constructs a general polygon from a range of x-monotone curves. It uses the operator void operator() (InputIterator begin, Input iterator end, Polygon_2 & pgn), parameterized by the InputIterator type.

GeneralPolygonSetTraits_2::Construct_curves_2
	a functor that returns a pair that consists of the begin and past-the-end iterators of the x monotone curves of the boundary of a given general polygon. It uses the operator std:pair<Curve_const_iterator, Curve_const_iterator> operator() (const Polygon_2 & pgn).

GeneralPolygonSetTraits_2::Is_valid_2
	provides the operators : bool operator() (Polygon_2 & pgn) which returns true if the pgn is valid, and false otherwise; and : bool operator() (Polygon_with_holes_2 & pgn_with_holes) which returns true if pgn_with_holes is valid, and false otherwise. A polygon of type Polygon_2 is valid, if it is strictly simple and oriented counterclockwise. A polygon of type Polygon_with_holes_2 is valid, if its outer boundary is simple and oriented counterclockwise, and each one of its holes is a strictly simple polygon that oriented clockwise, contained inside its outer boundary, and they are all together pairwise disjoint, except perhaps at the vertices. This functionality is used to verify precondition of some of the operations.

GeneralPolygonSetTraits_2::Construct_general_polygon_with_holes_2
	a functor that constructs a general polygon with holes from a general polygon and, optionally, a range of holes. It uses the operator void operator() (const General_polygon_2& pgn_boundary) or void operator() (const General_polygon_2& pgn_boundary, HolesInputIterator h_begin, HolesInputIterator h_end) parameterized by the HolesInputIterator type.

GeneralPolygonSetTraits_2::Construct_outer_boundary
	A functor for constructing the outer boundary of a polygon with holes. It uses the operator General_polygon_2 operator()(const General_polygon_with_holes_2& pol_wh).

GeneralPolygonSetTraits_2::Construct_holes
	A functor for constructing the container of holes of a polygon with holes. It returns the begin/end iterators for the holes It uses the operator std::pair<Hole_const_iterator, Hole_const_iterator> operator()(const General_polygon_with_holes_2& pol_wh).

GeneralPolygonSetTraits_2::Is_unbounded
	A functor for checking if polygon with holes has no outer boundary. It uses the operator bool operator()(const General_polygon_with_holes_2& pol_wh).

Creation

GeneralPolygonSetTraits_2 traits;
	default constructor.
GeneralPolygonSetTraits_2 traits ( other);
	copy constructor

GeneralPolygonSetTraits_2

traits = other

assignment operator.

Accessing Functor Objects

Construct_polygon_2	traits.construct_polygon_2_object ()
		returns a functor that constructs a polygon.

Construct_curves_2	traits.construct_curves_2_object ()
		returns a functor that obtains the curves of a polygon.

Is_valid_2	traits.is_valid_2_object ()	returns a functor that checks the validity of a polygon.

Construct_general_polygon_with_holes_2
	traits.construct_polygon_with_holes_2_object ()
		returns a functor that constructs a polygon with holes.

Construct_outer_boundary	traits.construct_outer_boundary_object ()
		returns a functor that obtains the outer boundary of a polygon with holes.

Construct_holes	traits.construct_holes_object ()	returns a functor that obtains begin/end iterators over a container of holes.

Is_unbounded	traits.construct_is_unbounded_object ()
		returns a functor that detemines if the polygon with holes is unbounded

Has Models

CGAL::Gps_segment_traits_2<Kernel,Container,ArrSegmentTraits>
CGAL::Gps_circle_segment_traits_2<Kernel>
CGAL::Gps_traits_2<ArrTraits,GeneralPolygon>