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boost/gil/extension/dynamic_image/any_image.hpp

/*
    Copyright 2005-2007 Adobe Systems Incorporated
   
    Use, modification and distribution are subject to 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).

    See http://opensource.adobe.com/gil for most recent version including documentation.
*/
/*************************************************************************************************/

#ifndef GIL_DYNAMICIMAGE_ANY_IMAGE_HPP
#define GIL_DYNAMICIMAGE_ANY_IMAGE_HPP

////////////////////////////////////////////////////////////////////////////////////////
/// \file               
/// \brief Support for run-time instantiated images and image views
/// \author Lubomir Bourdev and Hailin Jin \n
///         Adobe Systems Incorporated
///
///
////////////////////////////////////////////////////////////////////////////////////////

#include "any_image_view.hpp"
#include "../../image.hpp"

//#ifdef _MSC_VER
//#pragma warning(push)
//#pragma warning(disable : 4244)     // conversion from 'std::ptrdiff_t' to 'int', possible loss of data. even if we static-assert the two types are the same (on visual studio 8)
//#endif

namespace boost { namespace gil {

namespace detail {
    template <typename T> struct get_view_t       { typedef typename T::view_t type; };
    template <typename Images> struct images_get_views_t : public mpl::transform<Images, get_view_t<mpl::_1> > {};

    template <typename T> struct get_const_view_t { typedef typename T::const_view_t type; };
    template <typename Images> struct images_get_const_views_t : public mpl::transform<Images, get_const_view_t<mpl::_1> > {};

    struct recreate_image_fnobj {
        typedef void result_type;
        const point2<std::ptrdiff_t>& _dimensions;
        unsigned _alignment;

        recreate_image_fnobj(const point2<std::ptrdiff_t>& dims, unsigned alignment) : _dimensions(dims), _alignment(alignment) {}
        template <typename Image> result_type operator()(Image& img) const { img.recreate(_dimensions,_alignment); }
    };

    template <typename AnyView>  // Models AnyViewConcept
    struct any_image_get_view {
        typedef AnyView result_type;
        template <typename Image> result_type operator()(      Image& img) const { return result_type(view(img)); }
    };

    template <typename AnyConstView>  // Models AnyConstViewConcept
    struct any_image_get_const_view {
        typedef AnyConstView result_type;
        template <typename Image> result_type operator()(const Image& img) const { return result_type(const_view(img)); }
    };
}

////////////////////////////////////////////////////////////////////////////////////////
/// \ingroup ImageModel
/// \brief Represents a run-time specified image. Note it does NOT model ImageConcept
///  
/// Represents an image whose type (color space, layout, planar/interleaved organization, etc) can be specified at run time.
/// It is the runtime equivalent of \p image.
/// Some of the requirements of ImageConcept, such as the \p value_type typedef cannot be fulfilled, since the language does not allow runtime type specification.
/// Other requirements, such as access to the pixels, would be inefficient to provide. Thus \p any_image does not fully model ImageConcept.
/// In particular, its \p view and \p const_view methods return \p any_image_view, which does not fully model ImageViewConcept. See \p any_image_view for more.
////////////////////////////////////////////////////////////////////////////////////////
template <typename ImageTypes>
class any_image : public variant<ImageTypes> {
    typedef variant<ImageTypes> parent_t;
public:
    typedef any_image_view<typename detail::images_get_const_views_t<ImageTypes>::type> const_view_t;
    typedef any_image_view<typename detail::images_get_views_t<ImageTypes>::type>       view_t;
    typedef std::ptrdiff_t x_coord_t;
    typedef std::ptrdiff_t y_coord_t;
    typedef point2<std::ptrdiff_t> point_t;

    any_image()                                                          : parent_t() {}
    template <typename T> explicit any_image(const T& obj)               : parent_t(obj) {}
    template <typename T> explicit any_image(T& obj, bool do_swap)       : parent_t(obj,do_swap) {}
    any_image(const any_image& v)                                        : parent_t((const parent_t&)v)    {}

    template <typename T> any_image& operator=(const T& obj)             { parent_t::operator=(obj); return *this; }
    any_image&                       operator=(const any_image& v)       { parent_t::operator=((const parent_t&)v); return *this;}

    void recreate(const point_t& dims, unsigned alignment=1)               { apply_operation(*this,detail::recreate_image_fnobj(dims,alignment)); }
    void recreate(x_coord_t width, y_coord_t height, unsigned alignment=1) { recreate(point2<std::ptrdiff_t>(width,height),alignment); }

    std::size_t num_channels()  const { return apply_operation(*this, detail::any_type_get_num_channels()); }
    point_t     dimensions()    const { return apply_operation(*this, detail::any_type_get_dimensions()); }
    x_coord_t   width()         const { return dimensions().x; }
    y_coord_t   height()        const { return dimensions().y; }
};

///@{
/// \name view, const_view
/// \brief Get an image view from a run-time instantiated image

/// \ingroup ImageModel

/// \brief Returns the non-constant-pixel view of any image. The returned view is any view.
template <typename Types>  GIL_FORCEINLINE // Models ImageVectorConcept
typename any_image<Types>::view_t view(any_image<Types>& anyImage) { 
    return apply_operation(anyImage, detail::any_image_get_view<typename any_image<Types>::view_t>());
}

/// \brief Returns the constant-pixel view of any image. The returned view is any view.
template <typename Types> GIL_FORCEINLINE // Models ImageVectorConcept
typename any_image<Types>::const_view_t const_view(const any_image<Types>& anyImage) { 
    return apply_operation(anyImage, detail::any_image_get_const_view<typename any_image<Types>::const_view_t>());
}
///@}

} }  // namespace boost::gil

//#ifdef _MSC_VER
//#pragma warning(pop)
//#endif

#endif