/usr/include/CGAL/Homogeneous/basic_constructionsH2.h is in libcgal-dev 4.2-5ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 | // Copyright (c) 1999
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// 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; either version 3 of the License,
// or (at your option) any later version.
//
// 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) : Sven Schoenherr
// Stefan Schirra
#ifndef CGAL_BASIC_CONSTRUCTIONSH2_H
#define CGAL_BASIC_CONSTRUCTIONSH2_H
#include <CGAL/Homogeneous/PointH2.h>
#include <CGAL/Homogeneous/LineH2.h>
namespace CGAL {
template <class R>
CGAL_KERNEL_MEDIUM_INLINE
typename R::Point_2
gp_linear_intersection(const LineH2<R>& l1, const LineH2<R>& l2)
{
return typename R::Point_2( l1.b()*l2.c() - l2.b()*l1.c(),
l2.a()*l1.c() - l1.a()*l2.c(),
l1.a()*l2.b() - l2.a()*l1.b() );
}
template <class R>
CGAL_KERNEL_MEDIUM_INLINE
typename R::FT
squared_distance( const PointH2<R>& p, const PointH2<R>& q )
{
typedef typename R::RT RT;
typedef typename R::FT FT;
const RT & phx = p.hx();
const RT & phy = p.hy();
const RT & phw = p.hw();
const RT & qhx = q.hx();
const RT & qhy = q.hy();
const RT & qhw = q.hw();
RT sq_dist_numerator =
phx * phx * qhw * qhw
- RT(2) * phx * qhx * phw * qhw
+ qhx * qhx * phw * phw
+ phy * phy * qhw * qhw
- RT(2) * phy * qhy * phw * qhw
+ qhy * qhy * phw * phw ;
RT sq_dist_denominator = qhw * qhw * phw * phw ;
return FT( sq_dist_numerator ) / FT( sq_dist_denominator );
}
} //namespace CGAL
#endif // CGAL_BASIC_CONSTRUCTIONSH2_H
|