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Diffstat (limited to 'extern/Eigen2/Eigen/src/Core/util/Meta.h')
| -rw-r--r-- | extern/Eigen2/Eigen/src/Core/util/Meta.h | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/extern/Eigen2/Eigen/src/Core/util/Meta.h b/extern/Eigen2/Eigen/src/Core/util/Meta.h new file mode 100644 index 00000000000..c65c52ef42f --- /dev/null +++ b/extern/Eigen2/Eigen/src/Core/util/Meta.h @@ -0,0 +1,183 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. Eigen itself is part of the KDE project. +// +// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr> +// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com> +// +// Eigen is free software; 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. +// +// Alternatively, you can redistribute it and/or +// modify it under the terms of the GNU General Public License as +// published by the Free Software Foundation; either version 2 of +// the License, or (at your option) any later version. +// +// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License and a copy of the GNU General Public License along with +// Eigen. If not, see <http://www.gnu.org/licenses/>. + +#ifndef EIGEN_META_H +#define EIGEN_META_H + +/** \internal + * \file Meta.h + * This file contains generic metaprogramming classes which are not specifically related to Eigen. + * \note In case you wonder, yes we're aware that Boost already provides all these features, + * we however don't want to add a dependency to Boost. + */ + +struct ei_meta_true { enum { ret = 1 }; }; +struct ei_meta_false { enum { ret = 0 }; }; + +template<bool Condition, typename Then, typename Else> +struct ei_meta_if { typedef Then ret; }; + +template<typename Then, typename Else> +struct ei_meta_if <false, Then, Else> { typedef Else ret; }; + +template<typename T, typename U> struct ei_is_same_type { enum { ret = 0 }; }; +template<typename T> struct ei_is_same_type<T,T> { enum { ret = 1 }; }; + +template<typename T> struct ei_unref { typedef T type; }; +template<typename T> struct ei_unref<T&> { typedef T type; }; + +template<typename T> struct ei_unpointer { typedef T type; }; +template<typename T> struct ei_unpointer<T*> { typedef T type; }; +template<typename T> struct ei_unpointer<T*const> { typedef T type; }; + +template<typename T> struct ei_unconst { typedef T type; }; +template<typename T> struct ei_unconst<const T> { typedef T type; }; +template<typename T> struct ei_unconst<T const &> { typedef T & type; }; +template<typename T> struct ei_unconst<T const *> { typedef T * type; }; + +template<typename T> struct ei_cleantype { typedef T type; }; +template<typename T> struct ei_cleantype<const T> { typedef typename ei_cleantype<T>::type type; }; +template<typename T> struct ei_cleantype<const T&> { typedef typename ei_cleantype<T>::type type; }; +template<typename T> struct ei_cleantype<T&> { typedef typename ei_cleantype<T>::type type; }; +template<typename T> struct ei_cleantype<const T*> { typedef typename ei_cleantype<T>::type type; }; +template<typename T> struct ei_cleantype<T*> { typedef typename ei_cleantype<T>::type type; }; + +/** \internal + * Convenient struct to get the result type of a unary or binary functor. + * + * It supports both the current STL mechanism (using the result_type member) as well as + * upcoming next STL generation (using a templated result member). + * If none of these members is provided, then the type of the first argument is returned. FIXME, that behavior is a pretty bad hack. + */ +template<typename T> struct ei_result_of {}; + +struct ei_has_none {int a[1];}; +struct ei_has_std_result_type {int a[2];}; +struct ei_has_tr1_result {int a[3];}; + +template<typename Func, typename ArgType, int SizeOf=sizeof(ei_has_none)> +struct ei_unary_result_of_select {typedef ArgType type;}; + +template<typename Func, typename ArgType> +struct ei_unary_result_of_select<Func, ArgType, sizeof(ei_has_std_result_type)> {typedef typename Func::result_type type;}; + +template<typename Func, typename ArgType> +struct ei_unary_result_of_select<Func, ArgType, sizeof(ei_has_tr1_result)> {typedef typename Func::template result<Func(ArgType)>::type type;}; + +template<typename Func, typename ArgType> +struct ei_result_of<Func(ArgType)> { + template<typename T> + static ei_has_std_result_type testFunctor(T const *, typename T::result_type const * = 0); + template<typename T> + static ei_has_tr1_result testFunctor(T const *, typename T::template result<T(ArgType)>::type const * = 0); + static ei_has_none testFunctor(...); + + // note that the following indirection is needed for gcc-3.3 + enum {FunctorType = sizeof(testFunctor(static_cast<Func*>(0)))}; + typedef typename ei_unary_result_of_select<Func, ArgType, FunctorType>::type type; +}; + +template<typename Func, typename ArgType0, typename ArgType1, int SizeOf=sizeof(ei_has_none)> +struct ei_binary_result_of_select {typedef ArgType0 type;}; + +template<typename Func, typename ArgType0, typename ArgType1> +struct ei_binary_result_of_select<Func, ArgType0, ArgType1, sizeof(ei_has_std_result_type)> +{typedef typename Func::result_type type;}; + +template<typename Func, typename ArgType0, typename ArgType1> +struct ei_binary_result_of_select<Func, ArgType0, ArgType1, sizeof(ei_has_tr1_result)> +{typedef typename Func::template result<Func(ArgType0,ArgType1)>::type type;}; + +template<typename Func, typename ArgType0, typename ArgType1> +struct ei_result_of<Func(ArgType0,ArgType1)> { + template<typename T> + static ei_has_std_result_type testFunctor(T const *, typename T::result_type const * = 0); + template<typename T> + static ei_has_tr1_result testFunctor(T const *, typename T::template result<T(ArgType0,ArgType1)>::type const * = 0); + static ei_has_none testFunctor(...); + + // note that the following indirection is needed for gcc-3.3 + enum {FunctorType = sizeof(testFunctor(static_cast<Func*>(0)))}; + typedef typename ei_binary_result_of_select<Func, ArgType0, ArgType1, FunctorType>::type type; +}; + +/** \internal In short, it computes int(sqrt(\a Y)) with \a Y an integer. + * Usage example: \code ei_meta_sqrt<1023>::ret \endcode + */ +template<int Y, + int InfX = 0, + int SupX = ((Y==1) ? 1 : Y/2), + bool Done = ((SupX-InfX)<=1 ? true : ((SupX*SupX <= Y) && ((SupX+1)*(SupX+1) > Y))) > + // use ?: instead of || just to shut up a stupid gcc 4.3 warning +class ei_meta_sqrt +{ + enum { + MidX = (InfX+SupX)/2, + TakeInf = MidX*MidX > Y ? 1 : 0, + NewInf = int(TakeInf) ? InfX : int(MidX), + NewSup = int(TakeInf) ? int(MidX) : SupX + }; + public: + enum { ret = ei_meta_sqrt<Y,NewInf,NewSup>::ret }; +}; + +template<int Y, int InfX, int SupX> +class ei_meta_sqrt<Y, InfX, SupX, true> { public: enum { ret = (SupX*SupX <= Y) ? SupX : InfX }; }; + +/** \internal determines whether the product of two numeric types is allowed and what the return type is */ +template<typename T, typename U> struct ei_scalar_product_traits +{ + // dummy general case where T and U aren't compatible -- not allowed anyway but we catch it elsewhere + //enum { Cost = NumTraits<T>::MulCost }; + typedef T ReturnType; +}; + +template<typename T> struct ei_scalar_product_traits<T,T> +{ + //enum { Cost = NumTraits<T>::MulCost }; + typedef T ReturnType; +}; + +template<typename T> struct ei_scalar_product_traits<T,std::complex<T> > +{ + //enum { Cost = 2*NumTraits<T>::MulCost }; + typedef std::complex<T> ReturnType; +}; + +template<typename T> struct ei_scalar_product_traits<std::complex<T>, T> +{ + //enum { Cost = 2*NumTraits<T>::MulCost }; + typedef std::complex<T> ReturnType; +}; + +// FIXME quick workaround around current limitation of ei_result_of +template<typename Scalar, typename ArgType0, typename ArgType1> +struct ei_result_of<ei_scalar_product_op<Scalar>(ArgType0,ArgType1)> { +typedef typename ei_scalar_product_traits<typename ei_cleantype<ArgType0>::type, typename ei_cleantype<ArgType1>::type>::ReturnType type; +}; + + + +#endif // EIGEN_META_H |