PolygonTraits_2 Concept Reference

Definition

The CGAL::Polygon_2 class and the functions that implement the functionality found in that class each are parameterized by a traits class that defines the primitives used in the algorithms. The concept PolygonTraits_2 defines this common set of requirements.

The requirements of PolygonTraits_2 are a subset of the kernel requirements. We only list the types and methods which are required and refer to the description of the kernel concept for details.

Has Models:

The kernels supplied by CGAL are models of PolygonTraits_2.

CGAL::Projection_traits_xy_3<K>

CGAL::Projection_traits_yz_3<K>

CGAL::Projection_traits_xz_3<K>

See Also

CGAL::Polygon_2<PolygonTraits_2, Container>

Creation
	PolygonTraits_2 ()
	PolygonTraits_2 (const PolygonTraits_2 &)

Types
typedef unspecified_type	FT
typedef unspecified_type	Point_2
	The point type.
typedef unspecified_type	Segment_2
	The segment type.
typedef unspecified_type	Construct_segment_2
typedef unspecified_type	Equal_2
typedef unspecified_type	Less_xy_2
typedef unspecified_type	Less_yx_2
typedef unspecified_type	Compare_x_2
typedef unspecified_type	Compare_y_2
typedef unspecified_type	Orientation_2
typedef unspecified_type	Compute_area_2
	Computes the signed area of the oriented triangle defined by 3 Point_2 passed as arguments.

Operations
The following functions that create instances of the above predicate object types must exist.
Equal_2	equal_2_object ()
Less_xy_2	less_xy_2_object ()
Less_yx_2	less_yx_2_object ()
Compare_y_2	compare_y_2_object ()
Compare_x_2	compare_x_2_object ()
Orientation_2	orientation_2_object ()
Compute_area_2	compute_area_2_object ()
Construct_segment_2	construct_segment_2_object ()