cgal/Interval_support/include/CGAL/convert_to_bfi.h

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// Copyright (c) 2006-2009 Max-Planck-Institute Saarbruecken (Germany),
// INRIA Sophia-Antipolis (France).
// 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) : Michael Hemmer <hemmer@mpi-inf.mpg.de>
#ifndef CGAL_CONVERT_TO_BFI_H
#define CGAL_CONVERT_TO_BFI_H
#include <CGAL/basic.h>
#include <CGAL/Arithmetic_kernel.h>
#include <CGAL/Cache.h>
CGAL_BEGIN_NAMESPACE
template <class NTX>
typename Get_arithmetic_kernel<NTX>::Arithmetic_kernel::Bigfloat_interval
convert_to_bfi(const NTX& x) {
typedef typename Get_arithmetic_kernel<NTX>::Arithmetic_kernel AK;
typedef typename AK::Bigfloat_interval BFI;
typedef CGAL::Coercion_traits<NTX,BFI> CT;
return typename CT::Cast()(x);
// typedef typename Get_arithmetic_kernel<NTX>::Arithmetic_kernel AT;
// typedef typename AT::Bigfloat_interval BFI;
// typename Bigfloat_interval_traits<BFI>::Convert_to_bfi convert_to_bfi;
// return convert_to_bfi(x);
}
// Disbale SQRT_EXTENSION_TO_BFI_CACHE by default
#ifndef CGAL_USE_SQRT_EXTENSION_TO_BFI_CACHE
#define CGAL_USE_SQRT_EXTENSION_TO_BFI_CACHE 0
#endif
#if CGAL_USE_SQRT_EXTENSION_TO_BFI_CACHE
namespace INTERN_SQRT_EXTENSION {
template <typename BFI, typename NT, typename ROOT>
class Sqrt_extension_bfi_cache {
typedef std::pair<long , ROOT> Input;
typedef BFI Output;
typedef typename Coercion_traits<ROOT,BFI>::Cast Cast;
typedef typename Algebraic_structure_traits<BFI>::Sqrt Sqrt;
struct Creator : public std::unary_function<BFI,Input> {
BFI operator()(const Input& pair){
return Sqrt()(Cast()(pair.second));
}
};
}
public:
typedef Cache<Input,Output,Creator> Cache_type;
static Cache_type cache;
};
template <typename BFI, typename NT, typename ROOT>
typename Sqrt_extension_bfi_cache<BFI,NT,ROOT>::Cache_type
Sqrt_extension_bfi_cache<BFI,NT,ROOT>::cache;
} // namespace INTERN_SQRT_EXTENSION
// TODO: move this to sqrt_extension ?
template <typename A,typename B> class Sqrt_extension;
template <typename NT, typename ROOT>
typename Get_arithmetic_kernel<NT>::Arithmetic_kernel::Bigfloat_interval
convert_to_bfi(const CGAL::Sqrt_extension<NT,ROOT>& x) {
typedef typename Get_arithmetic_kernel<NT>::Arithmetic_kernel AK;
typedef typename AK::Bigfloat_interval BFI;
typedef Bigfloat_interval_traits<BFI> BFIT;
long precision = typename BFIT::Get_precision()();
BFI result;
if(x.is_extended()){
typedef INTERN_SQRT_EXTENSION::Sqrt_extension_bfi_cache<BFI,NT,ROOT> Get_cache;
BFI a0(convert_to_bfi(x.a0()));
BFI a1(convert_to_bfi(x.a1()));
BFI root(Get_cache::cache(std::make_pair(precision,x.root())));
result = a0+a1*root;
}else{
result = convert_to_bfi(x.a0());
}
#ifndef NDEBUG
BFI result_;
typedef typename Get_arithmetic_kernel<NT>::Arithmetic_kernel AT;
typedef typename AT::Bigfloat_interval BFI;
if(x.is_extended()){
BFI a0(convert_to_bfi(x.a0()));
BFI a1(convert_to_bfi(x.a1()));
BFI root(CGAL::sqrt(convert_to_bfi(x.root())));
result_ = a0+a1*root;
}else{
result_ = convert_to_bfi(x.a0());
}
assert(lower(result) == lower(result_));
assert(upper(result) == upper(result_));
#endif
return result;
}
#endif
CGAL_END_NAMESPACE
#endif // CGAL_CONVERT_TO_BFI_H