ceph/src/boost/boost/gil/extension/dynamic_image/any_image.hpp

   1 //
   2 // Copyright 2005-2007 Adobe Systems Incorporated
   3 // Copyright 2020 Samuel Debionne
   4 //
   5 // Distributed under the Boost Software License, Version 1.0
   6 // See accompanying file LICENSE_1_0.txt or copy at
   7 // http://www.boost.org/LICENSE_1_0.txt
   8 //
   9 #ifndef BOOST_GIL_EXTENSION_DYNAMIC_IMAGE_ANY_IMAGE_HPP
  10 #define BOOST_GIL_EXTENSION_DYNAMIC_IMAGE_ANY_IMAGE_HPP
  11
  12 #include <boost/gil/extension/dynamic_image/any_image_view.hpp>
  13 #include <boost/gil/extension/dynamic_image/apply_operation.hpp>
  14
  15 #include <boost/gil/image.hpp>
  16 #include <boost/gil/detail/mp11.hpp>
  17
  18 #include <boost/config.hpp>
  19 #include <boost/variant2/variant.hpp>
  20
  21 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
  22 #pragma warning(push)
  23 #pragma warning(disable:4512) //assignment operator could not be generated
  24 #endif
  25
  26 namespace boost { namespace gil {
  27
  28 namespace detail {
  29
  30 template <typename T>
  31 using get_view_t = typename T::view_t;
  32
  33 template <typename Images>
  34 using images_get_views_t = mp11::mp_transform<get_view_t, Images>;
  35
  36 template <typename T>
  37 using get_const_view_t = typename T::const_view_t;
  38
  39 template <typename Images>
  40 using images_get_const_views_t = mp11::mp_transform<get_const_view_t, Images>;
  41
  42 struct recreate_image_fnobj
  43 {
  44     using result_type = void;
  45     point<std::ptrdiff_t> const& _dimensions;
  46     unsigned _alignment;
  47
  48     recreate_image_fnobj(point<std::ptrdiff_t> const& dims, unsigned alignment)
  49         : _dimensions(dims), _alignment(alignment)
  50     {}
  51
  52     template <typename Image>
  53     result_type operator()(Image& img) const { img.recreate(_dimensions,_alignment); }
  54 };
  55
  56 template <typename AnyView>  // Models AnyViewConcept
  57 struct any_image_get_view
  58 {
  59     using result_type = AnyView;
  60     template <typename Image>
  61     result_type operator()(Image& img) const
  62     {
  63         return result_type(view(img));
  64     }
  65 };
  66
  67 template <typename AnyConstView>  // Models AnyConstViewConcept
  68 struct any_image_get_const_view
  69 {
  70     using result_type = AnyConstView;
  71     template <typename Image>
  72     result_type operator()(Image const& img) const { return result_type{const_view(img)}; }
  73 };
  74
  75 } // namespce detail
  76
  77 ////////////////////////////////////////////////////////////////////////////////////////
  78 /// \ingroup ImageModel
  79 /// \brief Represents a run-time specified image. Note it does NOT model ImageConcept
  80 ///
  81 /// Represents an image whose type (color space, layout, planar/interleaved organization, etc) can be specified at run time.
  82 /// It is the runtime equivalent of \p image.
  83 /// Some of the requirements of ImageConcept, such as the \p value_type alias cannot be fulfilled, since the language does not allow runtime type specification.
  84 /// Other requirements, such as access to the pixels, would be inefficient to provide. Thus \p any_image does not fully model ImageConcept.
  85 /// 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.
  86 ////////////////////////////////////////////////////////////////////////////////////////
  87
  88 template <typename ...Images>
  89 class any_image : public variant2::variant<Images...>
  90 {
  91     using parent_t = variant2::variant<Images...>;
  92 public:
  93     using view_t = mp11::mp_rename<detail::images_get_views_t<any_image>, any_image_view>;
  94     using const_view_t = mp11::mp_rename<detail::images_get_const_views_t<any_image>, any_image_view>;
  95     using x_coord_t = std::ptrdiff_t;
  96     using y_coord_t = std::ptrdiff_t;
  97     using point_t = point<std::ptrdiff_t>;
  98
  99     any_image() = default;
 100     any_image(any_image const& img) : parent_t((parent_t const&)img) {}
 101
 102     template <typename Image>
 103     explicit any_image(Image const& img) : parent_t(img) {}
 104
 105     template <typename Image>
 106     any_image(Image&& img) : parent_t(std::move(img)) {}
 107
 108     template <typename Image>
 109     explicit any_image(Image& img, bool do_swap) : parent_t(img, do_swap) {}
 110
 111     template <typename ...OtherImages>
 112     any_image(any_image<OtherImages...> const& img)
 113         : parent_t((variant2::variant<OtherImages...> const&)img)
 114     {}
 115
 116     any_image& operator=(any_image const& img)
 117     {
 118         parent_t::operator=((parent_t const&)img);
 119         return *this;
 120     }
 121
 122     template <typename Image>
 123     any_image& operator=(Image const& img)
 124     {
 125         parent_t::operator=(img);
 126         return *this;
 127     }
 128
 129     template <typename ...OtherImages>
 130     any_image& operator=(any_image<OtherImages...> const& img)
 131     {
 132             parent_t::operator=((typename variant2::variant<OtherImages...> const&)img);
 133             return *this;
 134     }
 135
 136     void recreate(const point_t& dims, unsigned alignment=1)
 137     {
 138         apply_operation(*this, detail::recreate_image_fnobj(dims, alignment));
 139     }
 140
 141     void recreate(x_coord_t width, y_coord_t height, unsigned alignment=1)
 142     {
 143         recreate({ width, height }, alignment);
 144     }
 145
 146     std::size_t num_channels() const
 147     {
 148         return apply_operation(*this, detail::any_type_get_num_channels());
 149     }
 150
 151     point_t dimensions() const
 152     {
 153         return apply_operation(*this, detail::any_type_get_dimensions());
 154     }
 155
 156     x_coord_t width()  const { return dimensions().x; }
 157     y_coord_t height() const { return dimensions().y; }
 158 };
 159
 160 ///@{
 161 /// \name view, const_view
 162 /// \brief Get an image view from a run-time instantiated image
 163
 164 /// \ingroup ImageModel
 165
 166 /// \brief Returns the non-constant-pixel view of any image. The returned view is any view.
 167 /// \tparam Images Models ImageVectorConcept
 168 template <typename ...Images>
 169 BOOST_FORCEINLINE
 170 auto view(any_image<Images...>& img) -> typename any_image<Images...>::view_t
 171 {
 172     using view_t = typename any_image<Images...>::view_t;
 173     return apply_operation(img, detail::any_image_get_view<view_t>());
 174 }
 175
 176 /// \brief Returns the constant-pixel view of any image. The returned view is any view.
 177 /// \tparam Types Models ImageVectorConcept
 178 template <typename ...Images>
 179 BOOST_FORCEINLINE
 180 auto const_view(any_image<Images...> const& img) -> typename any_image<Images...>::const_view_t
 181 {
 182     using view_t = typename any_image<Images...>::const_view_t;
 183     return apply_operation(img, detail::any_image_get_const_view<view_t>());
 184 }
 185 ///@}
 186
 187 }}  // namespace boost::gil
 188
 189 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
 190 #pragma warning(pop)
 191 #endif
 192
 193 #endif