Files
cpp-thirdparty/linx64/include/boost/gil/io/dynamic_io_new.hpp
2019-08-10 16:06:25 -05:00

101 lines
2.9 KiB
C++

//
// Copyright 2005-2007 Adobe Systems Incorporated
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
#ifndef BOOST_GIL_IO_DYNAMIC_IO_NEW_HPP
#define BOOST_GIL_IO_DYNAMIC_IO_NEW_HPP
#include <boost/gil/extension/dynamic_image/dynamic_image_all.hpp>
#include <boost/gil/io/error.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/size.hpp>
namespace boost { namespace gil {
namespace detail {
template <long N>
struct construct_matched_t {
template <typename Images,typename Pred>
static bool apply(any_image<Images>& im,Pred pred) {
if (pred.template apply<typename mpl::at_c<Images,N-1>::type>()) {
typename mpl::at_c<Images,N-1>::type x;
im = std::move(x);
return true;
} else return construct_matched_t<N-1>::apply(im,pred);
}
};
template <>
struct construct_matched_t<0> {
template <typename Images,typename Pred>
static bool apply(any_image<Images>&,Pred) {return false;}
};
// A function object that can be passed to apply_operation.
// Given a predicate IsSupported taking a view type and returning an MPL boolean,
// calls the apply method of OpClass with the view if the given view IsSupported, or throws an exception otherwise
template <typename IsSupported, typename OpClass>
class dynamic_io_fnobj {
OpClass* _op;
template <typename View>
void apply(const View& view,mpl::true_ ) {_op->apply(view);}
template <typename View, typename Info >
void apply( const View& view
, const Info& info
, const mpl::true_
)
{
_op->apply( view, info );
}
template <typename View>
void apply(const View& /* view */ ,mpl::false_) {io_error("dynamic_io: unsupported view type for the given file format");}
template <typename View, typename Info >
void apply( const View& /* view */
, const Info& /* info */
, const mpl::false_
)
{
io_error( "dynamic_io: unsupported view type for the given file format" );
}
public:
dynamic_io_fnobj(OpClass* op) : _op(op) {}
using result_type = void;
template <typename View>
void operator()(const View& view) {apply(view,typename IsSupported::template apply<View>::type());}
template< typename View, typename Info >
void operator()(const View& view, const Info& info )
{
apply( view
, info
, typename IsSupported::template apply< View >::type()
);
}
};
} // namespace detail
/// \brief Within the any_image, constructs an image with the given dimensions
/// and a type that satisfies the given predicate
template <typename Images,typename Pred>
inline bool construct_matched(any_image<Images>& im,Pred pred) {
return detail::construct_matched_t<mpl::size<Images>::value>::apply(im,pred);
}
} } // namespace boost::gil
#endif