straight_skeleton_cons_ftc2.h

很多二维 三维几何计算算法 C++ 类库

// Copyright (c) 2006 Fernando Luis Cacciola Carballal. All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you may redistribute it under
// the terms of the Q Public License version 1.0.
// See the file LICENSE.QPL 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: svn+ssh://scm.gforge.inria.fr/svn/cgal/branches/CGAL-3.3-branch/Straight_skeleton_2/include/CGAL/constructions/Straight_skeleton_cons_ftC2.h $
// $Id: Straight_skeleton_cons_ftC2.h 37120 2007-03-15 10:38:21Z hemmer $
//
// Author(s)     : Fernando Cacciola <[e-mail]>
//
#ifndef CGAL_STRAIGHT_SKELETON_CONS_FTC2_H
#define CGAL_STRAIGHT_SKELETON_CONS_FTC2_H 1

#include <CGAL/CORE_BigFloat.h>

CGAL_BEGIN_NAMESPACE 

namespace CGAL_SS_i
{

template<class NT>
inline NT inexact_sqrt( NT const& n )
{
  return CGAL_NTS sqrt(n);
}

inline MP_Float inexact_sqrt( MP_Float const& n )
{
  CORE::BigFloat nn( CGAL::to_double(n) ) ;
  CORE::BigFloat s = CORE::sqrt(nn);
  return MP_Float(s.doubleValue());
}

inline Quotient<MP_Float> inexact_sqrt( Quotient<MP_Float> const& q )
{
  CGAL_precondition(q > 0);
  return Quotient<MP_Float>(CGAL_SS_i::inexact_sqrt(q.numerator()*q.denominator())
                           ,q.denominator()
                           );
}


// Given an oriented 2D straight line segment 'e', computes the normalized coefficients (a,b,c) of the
// supporting line.
// POSTCONDITION: [a,b] is the leftward normal _unit_ (a