boost/gil/metafunctions.hpp
// // Copyright 2005-2007 Adobe Systems Incorporated // Copyright 2021 Pranam Lashkari <plashkari628@gmail.com> // // 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_METAFUNCTIONS_HPP #define BOOST_GIL_METAFUNCTIONS_HPP #include <boost/gil/channel.hpp> #include <boost/gil/dynamic_step.hpp> #include <boost/gil/concepts.hpp> #include <boost/gil/concepts/detail/type_traits.hpp> #include <boost/gil/detail/mp11.hpp> #include <iterator> #include <type_traits> namespace boost { namespace gil { // forward declarations template <typename T, typename L> struct pixel; template <typename BitField,typename ChannelRefs,typename Layout> struct packed_pixel; template <typename T, typename C> struct planar_pixel_reference; template <typename IC, typename C> struct planar_pixel_iterator; template <typename I> class memory_based_step_iterator; template <typename I> class memory_based_2d_locator; template <typename L> class image_view; template <typename Pixel, bool IsPlanar = false, typename Alloc=std::allocator<unsigned char> > class image; template <typename T> struct channel_type; template <typename T> struct color_space_type; template <typename T> struct channel_mapping_type; template <typename It> struct is_iterator_adaptor; template <typename It> struct iterator_adaptor_get_base; template <typename BitField, typename ChannelBitSizes, typename Layout, bool IsMutable> struct bit_aligned_pixel_reference; ////////////////////////////////////////////////// /// /// TYPE ANALYSIS METAFUNCTIONS /// Predicate metafunctions determining properties of GIL types /// ////////////////////////////////////////////////// /// \defgroup GILIsBasic xxx_is_basic /// \ingroup TypeAnalysis /// \brief Determines if GIL constructs are basic. /// Basic constructs are the ones that can be generated with the type /// factory methods pixel_reference_type, iterator_type, locator_type, view_type and image_type /// They can be mutable/immutable, planar/interleaved, step/nonstep. They must use GIL-provided models. /// \brief Determines if a given pixel reference is basic /// Basic references must use gil::pixel& (if interleaved), gil::planar_pixel_reference (if planar). They must use the standard constness rules. /// \ingroup GILIsBasic template <typename PixelRef> struct pixel_reference_is_basic : public std::false_type {}; template <typename T, typename L> struct pixel_reference_is_basic<pixel<T, L>&> : std::true_type {}; template <typename T, typename L> struct pixel_reference_is_basic<const pixel<T, L>&> : std::true_type {}; template <typename TR, typename CS> struct pixel_reference_is_basic<planar_pixel_reference<TR, CS>> : std::true_type {}; template <typename TR, typename CS> struct pixel_reference_is_basic<const planar_pixel_reference<TR, CS>> : std::true_type {}; /// \brief Determines if a given pixel iterator is basic /// Basic iterators must use gil::pixel (if interleaved), gil::planar_pixel_iterator (if planar) and gil::memory_based_step_iterator (if step). They must use the standard constness rules. /// \ingroup GILIsBasic template <typename Iterator> struct iterator_is_basic : std::false_type {}; /// \tparam T mutable interleaved pixel type template <typename T, typename L> struct iterator_is_basic<pixel<T, L>*> : std::true_type {}; /// \tparam T immutable interleaved pixel type template <typename T, typename L> struct iterator_is_basic<pixel<T, L> const*> : std::true_type {}; /// \tparam T mutable planar pixel type template <typename T, typename CS> struct iterator_is_basic<planar_pixel_iterator<T*, CS>> : std::true_type {}; /// \tparam T immutable planar pixel type template <typename T, typename CS> struct iterator_is_basic<planar_pixel_iterator<T const*, CS>> : std::true_type {}; /// \tparam T mutable interleaved step template <typename T, typename L> struct iterator_is_basic<memory_based_step_iterator<pixel<T, L>*>> : std::true_type {}; /// \tparam T immutable interleaved step template <typename T, typename L> struct iterator_is_basic<memory_based_step_iterator<pixel<T, L> const*>> : std::true_type {}; /// \tparam T mutable planar step template <typename T, typename CS> struct iterator_is_basic<memory_based_step_iterator<planar_pixel_iterator<T*, CS>>> : std::true_type {}; /// \tparam T immutable planar step template <typename T, typename CS> struct iterator_is_basic<memory_based_step_iterator<planar_pixel_iterator<T const*, CS>>> : std::true_type {}; /// \ingroup GILIsBasic /// \brief Determines if a given locator is basic. A basic locator is memory-based and has basic x_iterator and y_iterator template <typename Loc> struct locator_is_basic : std::false_type {}; template <typename Iterator> struct locator_is_basic < memory_based_2d_locator<memory_based_step_iterator<Iterator>> > : iterator_is_basic<Iterator> {}; /// \ingroup GILIsBasic /// \brief Basic views must be over basic locators template <typename View> struct view_is_basic : std::false_type {}; template <typename Loc> struct view_is_basic<image_view<Loc>> : locator_is_basic<Loc> {}; /// \ingroup GILIsBasic /// \brief Basic images must use basic views and std::allocator template <typename Img> struct image_is_basic : std::false_type {}; template <typename Pixel, bool IsPlanar, typename Alloc> struct image_is_basic<image<Pixel, IsPlanar, Alloc>> : std::true_type {}; /// \defgroup GILIsStep xxx_is_step /// \ingroup TypeAnalysis /// \brief Determines if the given iterator/locator/view has a step that could be set dynamically template <typename I> struct iterator_is_step; namespace detail { template <typename It, bool IsBase, bool EqualsStepType> struct iterator_is_step_impl; // iterator that has the same type as its dynamic_x_step_type must be a step iterator template <typename It, bool IsBase> struct iterator_is_step_impl<It, IsBase, true> : std::true_type {}; // base iterator can never be a step iterator template <typename It> struct iterator_is_step_impl<It, true, false> : std::false_type {}; // for an iterator adaptor, see if its base is step template <typename It> struct iterator_is_step_impl<It, false, false> : public iterator_is_step<typename iterator_adaptor_get_base<It>::type> {}; } // namespace detail /// \ingroup GILIsStep /// \brief Determines if the given iterator has a step that could be set dynamically template <typename I> struct iterator_is_step : detail::iterator_is_step_impl < I, !is_iterator_adaptor<I>::value, std::is_same<I, typename dynamic_x_step_type<I>::type >::value > {}; /// \ingroup GILIsStep /// \brief Determines if the given locator has a horizontal step that could be set dynamically template <typename L> struct locator_is_step_in_x : public iterator_is_step<typename L::x_iterator> {}; /// \ingroup GILIsStep /// \brief Determines if the given locator has a vertical step that could be set dynamically template <typename L> struct locator_is_step_in_y : public iterator_is_step<typename L::y_iterator> {}; /// \ingroup GILIsStep /// \brief Determines if the given view has a horizontal step that could be set dynamically template <typename V> struct view_is_step_in_x : public locator_is_step_in_x<typename V::xy_locator> {}; /// \ingroup GILIsStep /// \brief Determines if the given view has a vertical step that could be set dynamically template <typename V> struct view_is_step_in_y : public locator_is_step_in_y<typename V::xy_locator> {}; /// \brief Determines whether the given pixel reference is a proxy class or a native C++ reference /// \ingroup TypeAnalysis template <typename PixelReference> struct pixel_reference_is_proxy : mp11::mp_not < std::is_same < typename detail::remove_const_and_reference<PixelReference>::type, typename detail::remove_const_and_reference<PixelReference>::type::value_type > > {}; /// \brief Given a model of a pixel, determines whether the model represents a pixel reference (as opposed to pixel value) /// \ingroup TypeAnalysis template <typename Pixel> struct pixel_is_reference : mp11::mp_or<is_reference<Pixel>, pixel_reference_is_proxy<Pixel>> {}; /// \defgroup GILIsMutable xxx_is_mutable /// \ingroup TypeAnalysis /// \brief Determines if the given pixel reference/iterator/locator/view is mutable (i.e. its pixels can be changed) /// \ingroup GILIsMutable /// \brief Determines if the given pixel reference is mutable (i.e. its channels can be changed) /// /// Note that built-in C++ references obey the const qualifier but reference proxy classes do not. template <typename R> struct pixel_reference_is_mutable : std::integral_constant<bool, std::remove_reference<R>::type::is_mutable> {}; template <typename R> struct pixel_reference_is_mutable<R const&> : mp11::mp_and<pixel_reference_is_proxy<R>, pixel_reference_is_mutable<R>> {}; /// \ingroup GILIsMutable /// \brief Determines if the given locator is mutable (i.e. its pixels can be changed) template <typename L> struct locator_is_mutable : public iterator_is_mutable<typename L::x_iterator> {}; /// \ingroup GILIsMutable /// \brief Determines if the given view is mutable (i.e. its pixels can be changed) template <typename V> struct view_is_mutable : public iterator_is_mutable<typename V::x_iterator> {}; ////////////////////////////////////////////////// /// /// TYPE FACTORY METAFUNCTIONS /// Metafunctions returning GIL types from other GIL types /// ////////////////////////////////////////////////// /// \defgroup TypeFactoryFromElements xxx_type /// \ingroup TypeFactory /// \brief Returns the type of a homogeneous GIL construct given its elements (channel, layout, whether it is planar, step, mutable, etc.) /// \defgroup TypeFactoryFromPixel xxx_type_from_pixel /// \ingroup TypeFactory /// \brief Returns the type of a GIL construct given its pixel type, whether it is planar, step, mutable, etc. /// \defgroup TypeFactoryDerived derived_xxx_type /// \ingroup TypeFactory /// \brief Returns the type of a homogeneous GIL construct given a related construct by changing some of its properties /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous pixel reference given the channel type, layout, whether it operates on planar data and whether it is mutable template <typename T, typename L, bool IsPlanar=false, bool IsMutable=true> struct pixel_reference_type{}; template <typename T, typename L> struct pixel_reference_type<T,L,false,true > { using type = pixel<T,L>&; }; template <typename T, typename L> struct pixel_reference_type<T,L,false,false> { using type = pixel<T,L> const&; }; template <typename T, typename L> struct pixel_reference_type<T,L,true,true> { using type = planar_pixel_reference<typename channel_traits<T>::reference,typename color_space_type<L>::type> const; }; // TODO: Assert M=identity template <typename T, typename L> struct pixel_reference_type<T,L,true,false> { using type = planar_pixel_reference<typename channel_traits<T>::const_reference,typename color_space_type<L>::type> const; };// TODO: Assert M=identity /// \ingroup TypeFactoryFromPixel /// \brief Returns the type of a pixel iterator given the pixel type, whether it operates on planar data, whether it is a step iterator, and whether it is mutable template <typename Pixel, bool IsPlanar=false, bool IsStep=false, bool IsMutable=true> struct iterator_type_from_pixel{}; template <typename Pixel> struct iterator_type_from_pixel<Pixel,false,false,true > { using type = Pixel *; }; template <typename Pixel> struct iterator_type_from_pixel<Pixel,false,false,false> { using type = const Pixel *; }; template <typename Pixel> struct iterator_type_from_pixel<Pixel,true,false,true> { using type = planar_pixel_iterator<typename channel_traits<typename channel_type<Pixel>::type>::pointer,typename color_space_type<Pixel>::type>; }; template <typename Pixel> struct iterator_type_from_pixel<Pixel,true,false,false> { using type = planar_pixel_iterator<typename channel_traits<typename channel_type<Pixel>::type>::const_pointer,typename color_space_type<Pixel>::type>; }; template <typename Pixel, bool IsPlanar, bool IsMutable> struct iterator_type_from_pixel<Pixel,IsPlanar,true,IsMutable> { using type = memory_based_step_iterator<typename iterator_type_from_pixel<Pixel,IsPlanar,false,IsMutable>::type>; }; /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous iterator given the channel type, layout, whether it operates on planar data, whether it is a step iterator, and whether it is mutable template <typename T, typename L, bool IsPlanar=false, bool IsStep=false, bool IsMutable=true> struct iterator_type{}; template <typename T, typename L> struct iterator_type<T,L,false,false,true > { using type = pixel<T,L>*; }; template <typename T, typename L> struct iterator_type<T,L,false,false,false> { using type = pixel<T,L> const*; }; template <typename T, typename L> struct iterator_type<T,L,true,false,true> { using type = planar_pixel_iterator<T*,typename L::color_space_t>; }; // TODO: Assert M=identity template <typename T, typename L> struct iterator_type<T,L,true,false,false> { using type = planar_pixel_iterator<const T*,typename L::color_space_t>; }; // TODO: Assert M=identity template <typename T, typename L, bool IsPlanar, bool IsMutable> struct iterator_type<T,L,IsPlanar,true,IsMutable> { using type = memory_based_step_iterator<typename iterator_type<T,L,IsPlanar,false,IsMutable>::type>; }; /// \brief Given a pixel iterator defining access to pixels along a row, returns the types of the corresponding built-in step_iterator, xy_locator, image_view /// \ingroup TypeFactory template <typename XIterator> struct type_from_x_iterator { using step_iterator_t = memory_based_step_iterator<XIterator>; using xy_locator_t = memory_based_2d_locator<step_iterator_t>; using view_t = image_view<xy_locator_t>; }; namespace detail { template <typename BitField, typename FirstBit, typename NumBits> struct packed_channel_reference_type { using type = packed_channel_reference < BitField, FirstBit::value, NumBits::value, true > const; }; template <typename BitField, typename ChannelBitSizes> class packed_channel_references_vector_type { template <typename FirstBit, typename NumBits> using reference_type = typename packed_channel_reference_type<BitField, FirstBit, NumBits>::type; // If ChannelBitSizesVector is mp11::mp_list_c<int,7,7,2> // Then first_bits_vector will be mp11::mp_list_c<int,0,7,14,16> using first_bit_list = mp11::mp_fold_q < ChannelBitSizes, mp11::mp_list<std::integral_constant<int, 0>>, mp11::mp_bind < mp11::mp_push_back, mp11::_1, mp11::mp_bind < mp11::mp_plus, mp11::mp_bind<mp_back, mp11::_1>, mp11::_2 > > >; static_assert(mp11::mp_at_c<first_bit_list, 0>::value == 0, "packed channel first bit must be 0"); public: using type = mp11::mp_transform < reference_type, mp_pop_back<first_bit_list>, ChannelBitSizes >; }; } // namespace detail /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a packed pixel given its bitfield type, the bit size of its channels and its layout. /// /// A packed pixel has channels that cover bit ranges but itself is byte aligned. RGB565 pixel is an example. /// /// The size of ChannelBitSizes must equal the number of channels in the given layout /// The sum of bit sizes for all channels must be less than or equal to the number of bits in BitField (and cannot exceed 64). /// If it is less than the number of bits in BitField, the last bits will be unused. template <typename BitField, typename ChannelBitSizes, typename Layout> struct packed_pixel_type { using type = packed_pixel < BitField, typename detail::packed_channel_references_vector_type < BitField, ChannelBitSizes >::type, Layout>; }; /// \defgroup TypeFactoryPacked packed_image_type,bit_aligned_image_type /// \ingroup TypeFactoryFromElements /// \brief Returns the type of an image whose channels are not byte-aligned. /// /// A packed image is an image whose pixels are byte aligned, such as "rgb565". <br> /// A bit-aligned image is an image whose pixels are not byte aligned, such as "rgb222". <br> /// /// The sum of the bit sizes of all channels cannot exceed 64. /// \ingroup TypeFactoryPacked /// \brief Returns the type of an interleaved packed image: an image whose channels may not be byte-aligned, but whose pixels are byte aligned. template <typename BitField, typename ChannelBitSizes, typename Layout, typename Alloc=std::allocator<unsigned char>> struct packed_image_type { using type = image<typename packed_pixel_type<BitField,ChannelBitSizes,Layout>::type,false,Alloc>; }; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a single-channel image given its bitfield type, the bit size of its channel and its layout template <typename BitField, unsigned Size1, typename Layout, typename Alloc = std::allocator<unsigned char>> struct packed_image1_type : packed_image_type<BitField, mp11::mp_list_c<unsigned, Size1>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a two channel image given its bitfield type, the bit size of its channels and its layout template <typename BitField, unsigned Size1, unsigned Size2, typename Layout, typename Alloc = std::allocator<unsigned char>> struct packed_image2_type : packed_image_type<BitField, mp11::mp_list_c<unsigned, Size1, Size2>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a three channel image given its bitfield type, the bit size of its channels and its layout template <typename BitField, unsigned Size1, unsigned Size2, unsigned Size3, typename Layout, typename Alloc = std::allocator<unsigned char>> struct packed_image3_type : packed_image_type<BitField, mp11::mp_list_c<unsigned, Size1, Size2, Size3>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a four channel image given its bitfield type, the bit size of its channels and its layout template <typename BitField, unsigned Size1, unsigned Size2, unsigned Size3, unsigned Size4, typename Layout, typename Alloc = std::allocator<unsigned char>> struct packed_image4_type : packed_image_type<BitField, mp11::mp_list_c<unsigned, Size1, Size2, Size3, Size4>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a five channel image given its bitfield type, the bit size of its channels and its layout template <typename BitField, unsigned Size1, unsigned Size2, unsigned Size3, unsigned Size4, unsigned Size5, typename Layout, typename Alloc = std::allocator<unsigned char>> struct packed_image5_type : packed_image_type<BitField, mp11::mp_list_c<unsigned, Size1, Size2, Size3, Size4, Size5>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a packed image whose pixels may not be byte aligned. For example, an "rgb222" image is bit-aligned because its pixel spans six bits. /// /// Note that the alignment parameter in the constructor of bit-aligned images is in bit units. For example, if you want to construct a bit-aligned /// image whose rows are byte-aligned, use 8 as the alignment parameter, not 1. /// template < typename ChannelBitSizes, typename Layout, typename Alloc = std::allocator<unsigned char> > struct bit_aligned_image_type { private: static constexpr int bit_size = mp11::mp_fold < ChannelBitSizes, std::integral_constant<int, 0>, mp11::mp_plus >::value; using bitfield_t = typename detail::min_fast_uint<bit_size + 7>::type; using bit_alignedref_t = bit_aligned_pixel_reference<bitfield_t, ChannelBitSizes, Layout, true> const; public: using type = image<bit_alignedref_t,false,Alloc>; }; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a single-channel bit-aligned image given the bit size of its channel and its layout template <unsigned Size1, typename Layout, typename Alloc = std::allocator<unsigned char>> struct bit_aligned_image1_type : bit_aligned_image_type<mp11::mp_list_c<unsigned, Size1>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a two channel bit-aligned image given the bit size of its channels and its layout template <unsigned Size1, unsigned Size2, typename Layout, typename Alloc = std::allocator<unsigned char>> struct bit_aligned_image2_type : bit_aligned_image_type<mp11::mp_list_c<unsigned, Size1, Size2>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a three channel bit-aligned image given the bit size of its channels and its layout template <unsigned Size1, unsigned Size2, unsigned Size3, typename Layout, typename Alloc = std::allocator<unsigned char>> struct bit_aligned_image3_type : bit_aligned_image_type<mp11::mp_list_c<unsigned, Size1, Size2, Size3>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a four channel bit-aligned image given the bit size of its channels and its layout template <unsigned Size1, unsigned Size2, unsigned Size3, unsigned Size4, typename Layout, typename Alloc = std::allocator<unsigned char>> struct bit_aligned_image4_type : bit_aligned_image_type<mp11::mp_list_c<unsigned, Size1, Size2, Size3, Size4>, Layout, Alloc> {}; /// \ingroup TypeFactoryPacked /// \brief Returns the type of a five channel bit-aligned image given the bit size of its channels and its layout template <unsigned Size1, unsigned Size2, unsigned Size3, unsigned Size4, unsigned Size5, typename Layout, typename Alloc = std::allocator<unsigned char>> struct bit_aligned_image5_type : bit_aligned_image_type<mp11::mp_list_c<unsigned, Size1, Size2, Size3, Size4, Size5>, Layout, Alloc> {}; /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous pixel given the channel type and layout template <typename Channel, typename Layout> struct pixel_value_type { // by default use gil::pixel. Specializations are provided for using type = pixel<Channel, Layout>; }; // Specializations for packed channels template <typename BitField, int NumBits, bool IsMutable, typename Layout> struct pixel_value_type<packed_dynamic_channel_reference<BitField, NumBits, IsMutable>, Layout> : packed_pixel_type<BitField, mp11::mp_list_c<unsigned, NumBits>, Layout> {}; template <typename BitField, int NumBits, bool IsMutable, typename Layout> struct pixel_value_type<packed_dynamic_channel_reference<BitField, NumBits, IsMutable> const, Layout> : packed_pixel_type<BitField, mp11::mp_list_c<unsigned, NumBits>, Layout> {}; template <typename BitField, int FirstBit, int NumBits, bool IsMutable, typename Layout> struct pixel_value_type<packed_channel_reference<BitField, FirstBit, NumBits, IsMutable>, Layout> : packed_pixel_type<BitField, mp11::mp_list_c<unsigned, NumBits>, Layout> {}; template <typename BitField, int FirstBit, int NumBits, bool IsMutable, typename Layout> struct pixel_value_type<packed_channel_reference<BitField, FirstBit, NumBits, IsMutable> const, Layout> : packed_pixel_type<BitField, mp11::mp_list_c<unsigned, NumBits>, Layout> {}; template <int NumBits, typename Layout> struct pixel_value_type<packed_channel_value<NumBits>, Layout> : packed_pixel_type<typename detail::min_fast_uint<NumBits>::type, mp11::mp_list_c<unsigned, NumBits>, Layout> {}; /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous locator given the channel type, layout, whether it operates on planar data and whether it has a step horizontally template <typename T, typename L, bool IsPlanar = false, bool IsStepX = false, bool IsMutable = true> struct locator_type { using type = typename type_from_x_iterator < typename iterator_type<T, L, IsPlanar, IsStepX, IsMutable>::type >::xy_locator_type; }; /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous view given the channel type, layout, whether it operates on planar data and whether it has a step horizontally template <typename T, typename L, bool IsPlanar = false, bool IsStepX = false, bool IsMutable = true> struct view_type { using type = typename type_from_x_iterator < typename iterator_type<T, L, IsPlanar, IsStepX, IsMutable>::type >::view_t; }; /// \ingroup TypeFactoryFromElements /// \brief Returns the type of a homogeneous image given the channel type, layout, and whether it operates on planar data template <typename T, typename L, bool IsPlanar = false, typename Alloc = std::allocator<unsigned char>> struct image_type { using type = image<pixel<T, L>, IsPlanar, Alloc>; }; /// \ingroup TypeFactoryFromPixel /// \brief Returns the type of a view the pixel type, whether it operates on planar data and whether it has a step horizontally template <typename Pixel, bool IsPlanar=false, bool IsStepX=false, bool IsMutable=true> struct view_type_from_pixel { using type = typename type_from_x_iterator<typename iterator_type_from_pixel<Pixel,IsPlanar,IsStepX,IsMutable>::type>::view_t; }; /// \brief Constructs a pixel reference type from a source pixel reference type by changing some of the properties. /// \ingroup TypeFactoryDerived /// Use use_default for the properties of the source view that you want to keep template < typename Ref, typename T = use_default, typename L = use_default, typename IsPlanar = use_default, typename IsMutable = use_default> class derived_pixel_reference_type { using pixel_t = typename std::remove_reference<Ref>::type; using channel_t = typename mp11::mp_if < std::is_same<T, use_default>, typename channel_type<pixel_t>::type, T >::type; using layout_t = typename mp11::mp_if < std::is_same<L, use_default>, layout < typename color_space_type<pixel_t>::type, typename channel_mapping_type<pixel_t>::type >, L >::type; static bool const mut = mp11::mp_if < std::is_same<IsMutable, use_default>, pixel_reference_is_mutable<Ref>, IsMutable >::value; static bool const planar = mp11::mp_if < std::is_same<IsPlanar, use_default>, is_planar<pixel_t>, IsPlanar >::value; public: using type = typename pixel_reference_type<channel_t, layout_t, planar, mut>::type; }; /// \brief Constructs a pixel iterator type from a source pixel iterator type by changing some of the properties. /// \ingroup TypeFactoryDerived /// Use use_default for the properties of the source view that you want to keep template < typename Iterator, typename T = use_default, typename L = use_default, typename IsPlanar = use_default, typename IsStep = use_default, typename IsMutable = use_default > class derived_iterator_type { using channel_t = typename mp11::mp_if < std::is_same<T, use_default>, typename channel_type<Iterator>::type, T >::type; using layout_t = typename mp11::mp_if < std::is_same<L, use_default>, layout < typename color_space_type<Iterator>::type, typename channel_mapping_type<Iterator>::type >, L >::type; static const bool mut = mp11::mp_if < std::is_same<IsMutable, use_default>, iterator_is_mutable<Iterator>, IsMutable >::value; static bool const planar = mp11::mp_if < std::is_same<IsPlanar, use_default>, is_planar<Iterator>, IsPlanar >::value; static bool const step = mp11::mp_if < std::is_same<IsStep, use_default>, iterator_is_step<Iterator>, IsStep >::type::value; public: using type = typename iterator_type<channel_t, layout_t, planar, step, mut>::type; }; /// \brief Constructs an image view type from a source view type by changing some of the properties. /// \ingroup TypeFactoryDerived /// Use use_default for the properties of the source view that you want to keep template <typename View, typename T = use_default, typename L = use_default, typename IsPlanar = use_default, typename StepX = use_default, typename IsMutable = use_default> class derived_view_type { using channel_t = typename mp11::mp_if < std::is_same<T, use_default>, typename channel_type<View>::type, T >; using layout_t = typename mp11::mp_if < std::is_same<L, use_default>, layout < typename color_space_type<View>::type, typename channel_mapping_type<View>::type >, L >; static bool const mut = mp11::mp_if < std::is_same<IsMutable, use_default>, view_is_mutable<View>, IsMutable >::value; static bool const planar = mp11::mp_if < std::is_same<IsPlanar, use_default>, is_planar<View>, IsPlanar >::value; static bool const step = mp11::mp_if < std::is_same<StepX, use_default>, view_is_step_in_x<View>, StepX >::value; public: using type = typename view_type<channel_t, layout_t, planar, step, mut>::type; }; /// \brief Constructs a homogeneous image type from a source image type by changing some of the properties. /// \ingroup TypeFactoryDerived /// Use use_default for the properties of the source image that you want to keep template <typename Image, typename T = use_default, typename L = use_default, typename IsPlanar = use_default> class derived_image_type { using channel_t = typename mp11::mp_if < std::is_same<T, use_default>, typename channel_type<Image>::type, T >::type; using layout_t = typename mp11::mp_if < std::is_same<L, use_default>, layout < typename color_space_type<Image>::type, typename channel_mapping_type<Image>::type>, L >::type; static bool const planar = mp11::mp_if < std::is_same<IsPlanar, use_default>, is_planar<Image>, IsPlanar >::value; public: using type = typename image_type<channel_t, layout_t, planar>::type; }; }} // namespace boost::gil #endif