Weighted Offset Construction Functions

The following functions are used to construct the inward or outward weighted offsets of a polygon.

Functions
template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename HoleIterator , typename OfK , typename SsK >
std::vector< std::shared_ptr< OfKPolygon > >	CGAL::create_interior_weighted_skeleton_and_offset_polygons_2 (FT offset, const InKPolygon &outer_boundary, const InKWeights &outer_boundary_weights, HoleIterator holes_begin, HoleIterator holes_end, HoleWeightsIterator holes_weights_begin, HoleWeightsIterator holes_weights_end, OfK ofk=CGAL::Exact_predicates_inexact_constructions_kernel, SsK ssk=CGAL::Exact_predicates_inexact_constructions_kernel())
	returns a container with all the inner offset polygons at distance offset of a 2D polygon with holes.
template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename OfK , typename SsK >
std::vector< std::shared_ptr< OfKPolygon > >	CGAL::create_interior_weighted_skeleton_and_offset_polygons_2 (FT offset, const InKPolygon &poly, const InKWeights &weights, OfK ofk=CGAL::Exact_predicates_inexact_constructions_kernel, SsK ssk=CGAL::Exact_predicates_inexact_constructions_kernel())
	returns a container with all the inner offset polygons at distance offset of the 2D polygon poly.
template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename OfK , typename SsK >
std::vector< std::shared_ptr< OfKPolygon > >	CGAL::create_exterior_weighted_skeleton_and_offset_polygons_2 (FT offset, const InKPolygon &poly, const InKWeights &weights, OfK ofk=Exact_predicates_inexact_constructions_kernel(), SsK ssk=Exact_predicates_inexact_constructions_kernel())
	returns a container with all the outer offset polygons at distance offset of the 2D polygon poly.

Function Documentation

create_exterior_weighted_skeleton_and_offset_polygons_2()

template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename OfK , typename SsK >

std::vector< std::shared_ptr< OfKPolygon > > CGAL::create_exterior_weighted_skeleton_and_offset_polygons_2	(	FT	offset,
		const InKPolygon &	poly,
		const InKWeights &	weights,
		OfK	ofk = Exact_predicates_inexact_constructions_kernel(),
		SsK	ssk = Exact_predicates_inexact_constructions_kernel()
	)

#include <CGAL/create_weighted_offset_polygons_2.h>

returns a container with all the outer offset polygons at distance offset of the 2D polygon poly.

Weights of the polygon are given by weights, in the same order as the vertices of the polygon: the i-th weight in the range is associated to the contour edge between the i-1-th and i-th vertices.

The exterior skeleton is limited by an outer rectangular frame placed at a margin sufficiently large to allow the offset polygons to be constructed.

Note

A temporary straight skeleton is constructed in the limited exterior of the input polygon to obtain the offsets. The construction of this skeleton is the most expensive operation, therefore, to construct offsets at more than one single distance, use the separate functions create_exterior_straight_skeleton_2() and create_offset_polygons_2() instead.

Template Parameters

OfK	must be a model of Kernel. It is used to instantiate Polygon_offset_builder_traits_2<OfK> for constructing the offset polygons.
SsK	must be a model of Kernel. It is used to instantiate Straight_skeleton_builder_traits_2<SsK> for constructing the straight skeleton.
FT	must be a model of FieldNumberType convertible to OfK::FT and SsK::FT.
InKPolygon	must be a model of SequenceContainer with value type InK::Point_2 (e.g. Polygon_2<InK>) or a model of GeneralPolygonWithHoles_2 (e.g. Polygon_with_holes_2<InK>).
InKWeights	must be a model of Range with value type InK::FT.
OfKPolygon	is a polygon without holes type determined from OfK and InKPolygon, see Section Polygon Return Type.

Note

If SsK != OfK the constructed straight skeleton is converted to CGAL::Straight_skeleton_2<OfK>.

Precondition

offset is positive

poly` is weakly simple, counterclockwise polygon.

See also

CGAL::create_interior_skeleton_and_offset_polygons_2()

CGAL::create_exterior_skeleton_and_offset_polygons_with_holes_2()

Polygon_offset_builder_2

create_interior_weighted_skeleton_and_offset_polygons_2() [1/2]

template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename HoleIterator , typename OfK , typename SsK >

std::vector< std::shared_ptr< OfKPolygon > > CGAL::create_interior_weighted_skeleton_and_offset_polygons_2	(	FT	offset,
		const InKPolygon &	outer_boundary,
		const InKWeights &	outer_boundary_weights,
		HoleIterator	holes_begin,
		HoleIterator	holes_end,
		HoleWeightsIterator	holes_weights_begin,
		HoleWeightsIterator	holes_weights_end,
		OfK	ofk = CGAL::Exact_predicates_inexact_constructions_kernel,
		SsK	ssk = CGAL::Exact_predicates_inexact_constructions_kernel()
	)

#include <CGAL/create_weighted_offset_polygons_2.h>

returns a container with all the inner offset polygons at distance offset of a 2D polygon with holes.

The outer boundary is outer_boundary and its holes are given by [holes_begin,holes_end). Weights of the outer contour are given by outer_boundary_weights and weights of the holes are given by [holes_weights_begin, holes_weights_end], in the same order as holes appear in the iterator range. Within each weight range, weights are given in the same order as the vertices of the contour: the i-th weight in the range is associated to the contour edge between the i-1-th and i-th vertices.

Note

A temporary straight skeleton is constructed in the interior of the input polygon to obtain the offsets. The construction of this skeleton is the most expensive operation, therefore, to construct offsets at more than one single distance, it is advised to use the separate functions create_interior_straight_skeleton_2() and create_offset_polygons_2() instead.

Template Parameters

OfK	must be a model of Kernel. It is used to instantiate Polygon_offset_builder_traits_2<OfK> for constructing the offset polygons.
SsK	must be a model of Kernel. It is used to instantiate Straight_skeleton_builder_traits_2<SsK> for constructing the straight skeleton.
FT	must be a model of FieldNumberType convertible to OfK::FT and SsK::FT.
InKPolygon	must be a model of SequenceContainer with value type InK::Point_2 (e.g. Polygon_2<InK>).
InKWeights	must be a model of Range with value type InK::FT.
HoleIterator	must be a model of InputIterator with value type being a model of ConstRange with value type SsK::Point_2.
HoleWeightsIterator	must be a model of InputIterator with value type being a model of ConstRange with value type InK::FT.
OfKPolygon	is a polygon without holes type determined from OfK and InKPolygon, see Section Polygon Return Type.

Note

If SsK != OfK the constructed straight skeleton is converted to CGAL::Straight_skeleton_2<OfK>.

See also

CGAL::create_exterior_skeleton_and_offset_polygons_2()

CGAL::create_interior_skeleton_and_offset_polygons_with_holes_2()

Polygon_offset_builder_2

create_interior_weighted_skeleton_and_offset_polygons_2() [2/2]

template<typename OfKPolygon , typename FT , typename InKPolygon , typename InKWeights , typename OfK , typename SsK >

std::vector< std::shared_ptr< OfKPolygon > > CGAL::create_interior_weighted_skeleton_and_offset_polygons_2	(	FT	offset,
		const InKPolygon &	poly,
		const InKWeights &	weights,
		OfK	ofk = CGAL::Exact_predicates_inexact_constructions_kernel,
		SsK	ssk = CGAL::Exact_predicates_inexact_constructions_kernel()
	)

#include <CGAL/create_weighted_offset_polygons_2.h>

returns a container with all the inner offset polygons at distance offset of the 2D polygon poly.

Weights of the polygon are given by weights, in the same order as the vertices of the polygon: the i-th weight in the range is associated to the contour edge between the i-1-th and i-th vertices.

Note

A temporary straight skeleton is constructed in the interior of the input polygon to obtain the offsets. The construction of this skeleton is the most expensive operation, therefore, to construct offsets at more than one single distance, use the separate functions create_interior_straight_skeleton_2() and create_offset_polygons_2() instead.

Template Parameters

OfK	must be a model of Kernel. It is used to instantiate Polygon_offset_builder_traits_2<OfK> for constructing the offset polygons.
SsK	must be a model of Kernel. It is used to instantiate Straight_skeleton_builder_traits_2<SsK> for constructing the straight skeleton.
FT	must be a model of FieldNumberType convertible to OfK::FT and SsK::FT.
InKPolygon	must be a model of SequenceContainer with value type InK::Point_2 (e.g. Polygon_2<InK>) or a model of GeneralPolygonWithHoles_2 (e.g. Polygon_with_holes_2<InK>).
InKWeights	must be a model of Range with value type InK::FT.
OfKPolygon	is a polygon without holes type determined by OfK and InKPolygon, see Section Polygon Return Type.

Note

If SsK != OfK the constructed straight skeleton is converted to CGAL::Straight_skeleton_2<OfK>.

See also

CGAL::create_exterior_skeleton_and_offset_polygons_2()

CGAL::create_interior_skeleton_and_offset_polygons_with_holes_2()

Polygon_offset_builder_2