cgal/Cartesian_kernel/include/CGAL/Cartesian/Circle_2.h

107 lines
3.1 KiB
C++

// Copyright (c) 1997-2004 Utrecht University (The Netherlands),
// ETH Zurich (Switzerland), Freie Universitaet Berlin (Germany),
// INRIA Sophia-Antipolis (France), Martin-Luther-University Halle-Wittenberg
// (Germany), Max-Planck-Institute Saarbruecken (Germany), RISC Linz (Austria),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; version 2.1 of the License.
// See the file LICENSE.LGPL distributed with CGAL.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
//
//
// Author(s) : Andreas Fabri, Herve Bronnimann
#ifndef CGAL_CARTESIAN_CIRCLE_2_H
#define CGAL_CARTESIAN_CIRCLE_2_H
#include <CGAL/utility.h>
#include <CGAL/Interval_arithmetic.h>
#include <CGAL/Cartesian/predicates_on_points_2.h>
CGAL_BEGIN_NAMESPACE
template <class R_ >
class CircleC2
{
typedef typename R_::FT FT;
typedef typename R_::RT RT;
typedef typename R_::Circle_2 Circle_2;
typedef typename R_::Point_2 Point_2;
typedef typename R_::Aff_transformation_2 Aff_transformation_2;
typedef Triple<Point_2, FT, Orientation> Rep;
typedef typename R_::template Handle<Rep>::type Base;
Base base;
public:
typedef R_ R;
CircleC2() {}
CircleC2(const Point_2 &center, const FT &squared_radius = FT(0),
const Orientation &orient = COUNTERCLOCKWISE) // Is this new?
{
CGAL_kernel_precondition( ( squared_radius >= FT(0) ) &&
( orient != COLLINEAR) );
base = Rep(center, squared_radius, orient);
}
bool operator==(const CircleC2 &s) const;
bool operator!=(const CircleC2 &s) const;
const Point_2 & center() const
{
return get(base).first;
}
const FT & squared_radius() const
{
return get(base).second;
}
Orientation orientation() const
{
return get(base).third;
}
Circle_2 orthogonal_transform(const Aff_transformation_2 &t) const;
};
template < class R >
CGAL_KERNEL_INLINE
typename CircleC2<R>::Circle_2
CircleC2<R>::orthogonal_transform
(const typename CircleC2<R>::Aff_transformation_2 &t) const
{
typename R::Vector_2 vec(RT(1), RT(0) ); // unit vector // AF: was FT
vec = vec.transform(t); // transformed
FT sq_scale = vec.squared_length(); // squared scaling factor
return CircleC2<R>(t.transform(center()),
sq_scale * squared_radius(),
t.is_even() ? orientation()
: CGAL::opposite(orientation()));
}
CGAL_END_NAMESPACE
#endif // CGAL_CARTESIAN_CIRCLE_2_H