CGAL::Hot_pixel_snap_rounding_traits_2< Base_kernel > Class Template Reference

#include <CGAL/Hot_pixel_snap_rounding_traits_2.h>

Inherits from

CGAL::Arr_segment_traits_2< Base_kernel >.

Definition

template<class Base_kernel>
class CGAL::Hot_pixel_snap_rounding_traits_2< Base_kernel >

The class Hot_pixel_snap_rounding_traits_2<Kernel> is a model of the HotPixelSnapRoundingTraits_2 concept.

This class should be instantiated with an exact geometric kernel that conforms to the CGAL kernel-concept, such as the Exact_predicates_exact_constructions_kernel, or Cartesian<Gmpq>.

This geometric kernel must provide an (arbitrary-precision) rational number type (FT), Point_2, Segment_2 and Iso_rectangle_2. It should be possible to cast numbers of the number type FT to double-precision representation. That is, the function CGAL::to_double(FT) must be supported.

The CGAL::to_double() function is used to implement the operation that rounds the coordinates of a point to a center of a pixel. This operation is one of the traits-concept requirement. The coordinates are converted to double, rounded down to the nearest grid point, and finally adjusted to lie on a center of a pixel. Notice that if CGAL::to_double() returns the closet value, then when it rounds up a given coordinate, the resulting ISR, may be imprecise, and the distance between some vertex and a non-incident edge can be slightly less than the guaranteed half-the width-of-a-pixel.

Is model of

HotPixelSnapRoundingTraits_2

Examples

Snap_rounding_2/snap_rounding.cpp.

Classes
class	Integer_grid_point_2
	Functor. More...
class	Minkowski_sum_with_pixel_2
	Functor. More...
class	Snap_2
	Functor. More...

Public Types
typedef Base_kernel::FT	NT
typedef Base_kernel::FT	FT
typedef Base_kernel::Point_2	Point_2
typedef Base_kernel::Segment_2	Segment_2
typedef Base_kernel::Iso_rectangle_2	Iso_rectangle_2
typedef Base_kernel::Vector_2	Vector_2
typedef Base_kernel::Line_2	Line_2
typedef Base_kernel::Aff_transformation_2	Aff_transformation_2
typedef Base_kernel::Direction_2	Direction_2
typedef Base_kernel::Construct_vertex_2	Construct_vertex_2
typedef Base_kernel::Construct_segment_2	Construct_segment_2
typedef Base_kernel::Construct_iso_rectangle_2	Construct_iso_rectangle_2
typedef Base_kernel::Compare_y_2	Compare_y_2
typedef Base_kernel::Construct_min_vertex_2	Construct_min_vertex_2
typedef Base_kernel::Construct_max_vertex_2	Construct_max_vertex_2
typedef Base_kernel::Cartesian_const_iterator_2	Cartesian_const_iterator_2
typedef Base_kernel::Construct_cartesian_const_iterator_2	Construct_cartesian_const_iterator_2
typedef CGAL::Arr_segment_traits_2< Base_kernel >	Base_traits
typedef Base_traits::Compare_x_2	Compare_x_2
typedef CGAL::To_double< NT >	To_double
Public Types inherited from CGAL::Arr_segment_traits_2< Base_kernel >
typedef X_monotone_curve_2	Curve_2
typedef Kernel::Segment_2	Segment_2
typedef Kernel::Line_2	Line_2
typedef Kernel::Point_2	Point_2

Public Member Functions
Snap_2	snap_2_object () const
Integer_grid_point_2	integer_grid_point_2_object () const
Minkowski_sum_with_pixel_2	minkowski_sum_with_pixel_2_object () const
Construct_segment_2	construct_segment_2_object () const
Construct_vertex_2	construct_vertex_2_object () const
Compare_y_2	compare_y_2_object () const
Construct_iso_rectangle_2	construct_iso_rectangle_2_object () const