text: //
  // Copyright 2019 Mateusz Loskot <mateusz at loskot dot net>
  // 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_TEST_CORE_PIXEL_TEST_FIXTURE_HPP
  #define BOOST_GIL_TEST_CORE_PIXEL_TEST_FIXTURE_HPP
  
  #include <boost/gil/channel.hpp>
  #include <boost/gil/color_base_algorithm.hpp>
  #include <boost/gil/concepts/pixel.hpp>
  #include <boost/gil/packed_pixel.hpp>
  #include <boost/gil/pixel.hpp>
  #include <boost/gil/planar_pixel_reference.hpp>
  #include <boost/gil/promote_integral.hpp>
  #include <boost/gil/typedefs.hpp>
  #include <boost/gil/extension/toolbox/metafunctions/channel_type.hpp> // channel_type for packed and bit-aligned pixels
  
  #include <boost/core/ignore_unused.hpp>
  #include <boost/mp11.hpp>
  
  #include <cstdint>
  #include <iterator>
  #include <tuple>
  #include <type_traits>
  
  #include "core/test_fixture.hpp" // random_value
  #include "core/channel/test_fixture.hpp" // channel_minmax_value
  
  namespace boost { namespace gil { namespace test { namespace fixture {
  
  template <typename Pixel>
  struct pixel_generator
  {
      using channel_t = typename gil::channel_type<Pixel>::type;
  
      static auto max() -> Pixel
      {
          channel_minmax_value<channel_t> channel;
          Pixel pixel;
          gil::static_fill(pixel, channel.max_v_);
          return pixel;
      }
  
      static auto min()-> Pixel
      {
          channel_minmax_value<channel_t> channel;
          Pixel pixel;
          gil::static_fill(pixel, channel.min_v_);
          return pixel;
      }
  
      static auto random() -> Pixel
      {
          random_value<channel_t> generate;
          Pixel pixel;
          gil::static_generate(pixel, [&generate]() { return generate(); });
          return pixel;
      }
  };
  
  template <typename Pixel, int Tag = 0>
  class pixel_value
  {
  public:
      using type = Pixel;
      using pixel_t = type;
      type pixel_;
  
      pixel_value() = default;
      explicit pixel_value(pixel_t const& pixel)
          : pixel_(pixel) // test copy constructor
      {
          type temp_pixel; // test default constructor
          boost::ignore_unused(temp_pixel);
          boost::function_requires<PixelValueConcept<pixel_t> >();
      }
  };
  
  // Alias compatible with naming of equivalent class in the test/legacy/pixel.cpp
  // The core suffix indicates `Pixel` is GIL core pixel type.
  template <typename Pixel, int Tag = 0>
  using value_core = pixel_value<Pixel, Tag>;
  
  template <typename PixelRef, int Tag = 0>
  struct pixel_reference
      : pixel_value
      <
          typename std::remove_reference<PixelRef>::type,
          Tag
      >
  {
      static_assert(
          std::is_reference<PixelRef>::value ||
          gil::is_planar<PixelRef>::value, // poor-man test for specialization of planar_pixel_reference
          "PixelRef must be reference or gil::planar_pixel_reference");
  
      using type = PixelRef;
      using pixel_t = typename std::remove_reference<PixelRef>::type;
      using parent_t = pixel_value<typename pixel_t::value_type, Tag>;
      using value_t = typename pixel_t::value_type;
      type pixel_; // reference
  
      pixel_reference() : parent_t{}, pixel_(parent_t::pixel_) {}
      explicit pixel_reference(value_t const& pixel) : parent_t(pixel), pixel_(parent_t::pixel_)
      {
          boost::function_requires<PixelConcept<pixel_t>>();
      }
  };
  
  // Alias compatible with naming of equivalent class in the test/legacy/pixel.cpp
  // The core suffix indicates `Pixel` is GIL core pixel type.
  template <typename Pixel, int Tag = 0>
  using reference_core = pixel_reference<Pixel, Tag>;
  
  // Metafunction to yield nested type of a representative pixel type
  template <typename PixelValueOrReference>
  using nested_type = typename PixelValueOrReference::type;
  
  // Metafunction to yield nested type of a representative pixel_t type
  template <typename PixelValueOrReference>
  using nested_pixel_type = typename PixelValueOrReference::pixel_t;
  
  // Subset of pixel models that covers all color spaces, channel depths,
  // reference/value, planar/interleaved, const/mutable.
  // Operations like color conversion will be invoked on pairs of those.
  using representative_pixel_types= ::boost::mp11::mp_list
  <
      value_core<gil::gray8_pixel_t>,
      reference_core<gil::gray16_pixel_t&>,
      value_core<gil::bgr8_pixel_t>,
      reference_core<gil::rgb8_planar_ref_t>,
      value_core<gil::argb32_pixel_t>,
      reference_core<gil::cmyk32f_pixel_t&>,
      reference_core<gil::abgr16c_ref_t>, // immutable reference
      reference_core<gil::rgb32fc_planar_ref_t>
  >;
  
  // List of all integer-based core pixel typedefs (i.e. with cv-qualifiers)
  using pixel_integer_types = ::boost::mp11::mp_list
  <
      gil::gray8_pixel_t,
      gil::gray8s_pixel_t,
      gil::gray16_pixel_t,
      gil::gray16s_pixel_t,
      gil::gray32_pixel_t,
      gil::gray32s_pixel_t,
      gil::bgr8_pixel_t,
      gil::bgr8s_pixel_t,
      gil::bgr16_pixel_t,
      gil::bgr16s_pixel_t,
      gil::bgr32_pixel_t,
      gil::bgr32s_pixel_t,
      gil::rgb8_pixel_t,
      gil::rgb8s_pixel_t,
      gil::rgb16_pixel_t,
      gil::rgb16s_pixel_t,
      gil::rgb32_pixel_t,
      gil::rgb32s_pixel_t,
      gil::abgr8_pixel_t,
      gil::abgr8s_pixel_t,
      gil::abgr16_pixel_t,
      gil::abgr16s_pixel_t,
      gil::abgr32_pixel_t,
      gil::abgr32s_pixel_t,
      gil::bgra8_pixel_t,
      gil::bgra8s_pixel_t,
      gil::bgra16_pixel_t,
      gil::bgra16s_pixel_t,
      gil::bgra32_pixel_t,
      gil::bgra32s_pixel_t,
      gil::cmyk8_pixel_t,
      gil::cmyk8s_pixel_t,
      gil::cmyk16_pixel_t,
      gil::cmyk16s_pixel_t,
      gil::cmyk32_pixel_t,
      gil::cmyk32s_pixel_t,
      gil::rgba8_pixel_t,
      gil::rgba8s_pixel_t,
      gil::rgba16_pixel_t,
      gil::rgba16s_pixel_t,
      gil::rgba32_pixel_t,
      gil::rgba32s_pixel_t
  >;
  
  // List of all integer-based core pixel typedefs (i.e. with cv-qualifiers)
  using pixel_float_types = ::boost::mp11::mp_list
  <
      gil::gray32f_pixel_t,
      gil::bgr32f_pixel_t,
      gil::rgb32f_pixel_t,
      gil::abgr32f_pixel_t,
      gil::bgra32f_pixel_t,
      gil::cmyk32f_pixel_t,
      gil::rgba32f_pixel_t
  >;
  
  // List of all core pixel types (i.e. without cv-qualifiers)
  using pixel_types = ::boost::mp11::mp_append
  <
      pixel_integer_types,
      pixel_float_types
  >;
  
  // List of all core pixel typedefs (i.e. with cv-qualifiers)
  using pixel_typedefs = ::boost::mp11::mp_append
  <
      pixel_integer_types,
      pixel_float_types,
      ::boost::mp11::mp_list
      <
          gil::gray8c_pixel_t,
          gil::gray8sc_pixel_t,
          gil::gray16c_pixel_t,
          gil::gray16sc_pixel_t,
          gil::gray32c_pixel_t,
          gil::gray32fc_pixel_t,
          gil::gray32sc_pixel_t,
          gil::bgr8c_pixel_t,
          gil::bgr8sc_pixel_t,
          gil::bgr16c_pixel_t,
          gil::bgr16sc_pixel_t,
          gil::bgr32c_pixel_t,
          gil::bgr32fc_pixel_t,
          gil::bgr32sc_pixel_t,
          gil::rgb8c_pixel_t,
          gil::rgb8sc_pixel_t,
          gil::rgb16c_pixel_t,
          gil::rgb16sc_pixel_t,
          gil::rgb32c_pixel_t,
          gil::rgb32fc_pixel_t,
          gil::rgb32sc_pixel_t,
          gil::abgr8c_pixel_t,
          gil::abgr8sc_pixel_t,
          gil::abgr16c_pixel_t,
          gil::abgr16sc_pixel_t,
          gil::abgr32c_pixel_t,
          gil::abgr32fc_pixel_t,
          gil::abgr32sc_pixel_t,
          gil::bgra8c_pixel_t,
          gil::bgra8sc_pixel_t,
          gil::bgra16c_pixel_t,
          gil::bgra16sc_pixel_t,
          gil::bgra32c_pixel_t,
          gil::bgra32fc_pixel_t,
          gil::bgra32sc_pixel_t,
          gil::cmyk8c_pixel_t,
          gil::cmyk8sc_pixel_t,
          gil::cmyk16c_pixel_t,
          gil::cmyk16sc_pixel_t,
          gil::cmyk32c_pixel_t,
          gil::cmyk32fc_pixel_t,
          gil::cmyk32sc_pixel_t,
          gil::rgba8c_pixel_t,
          gil::rgba8sc_pixel_t,
          gil::rgba16c_pixel_t,
          gil::rgba16sc_pixel_t,
          gil::rgba32c_pixel_t,
          gil::rgba32fc_pixel_t,
          gil::rgba32sc_pixel_t
      >
  >;
  
  struct not_a_pixel_type {};
  
  using non_pixels = ::boost::mp11::mp_list
  <
      not_a_pixel_type,
      char,
      short, int, long,
      double, float,
      std::size_t,
      std::true_type,
      std::false_type
  >;
  
  using packed_channel_references_3 = typename gil::detail::packed_channel_references_vector_type
  <
      std::uint8_t,
      mp11::mp_list_c<int, 3>
  >::type;
  
  using packed_pixel_gray3 = gil::packed_pixel
  <
      std::uint8_t,
      packed_channel_references_3,
      gil::gray_layout_t
  >;
  
  using packed_channel_references_121 = typename gil::detail::packed_channel_references_vector_type
  <
      std::uint8_t,
      mp11::mp_list_c<int, 1, 2, 1>
  >::type;
  
  using packed_pixel_bgr121 = gil::packed_pixel
  <
      std::uint8_t,
      packed_channel_references_121,
      gil::bgr_layout_t
  >;
  
  using packed_channel_references_535 = typename gil::detail::packed_channel_references_vector_type
  <
      std::uint16_t,
      mp11::mp_list_c<int, 5, 3, 5>
  >::type;
  
  using packed_pixel_rgb535 = gil::packed_pixel
  <
      std::uint16_t,
      packed_channel_references_535,
      gil::rgb_layout_t
  >;
  
  using bit_aligned_pixel_bgr232_refefence = gil::bit_aligned_pixel_reference
      <
          std::uint8_t,
          mp11::mp_list_c<int, 2, 3, 2>,
          gil::bgr_layout_t,
          true
      > const;
  
  using bit_aligned_pixel_bgr232_iterator = bit_aligned_pixel_iterator<bit_aligned_pixel_bgr232_refefence>;
  
  using bit_aligned_pixel_bgr232 = std::iterator_traits<bit_aligned_pixel_bgr232_iterator>::value_type;
  
  using bit_aligned_pixel_rgb567_refefence = gil::bit_aligned_pixel_reference
      <
          std::uint32_t,
          mp11::mp_list_c<int, 5, 6, 7>,
          gil::rgb_layout_t,
          true
      > const;
  
  using bit_aligned_pixel_rgb567_iterator = bit_aligned_pixel_iterator<bit_aligned_pixel_rgb567_refefence>;
  
  using bit_aligned_pixel_rgb567 = std::iterator_traits<bit_aligned_pixel_rgb567_iterator>::value_type;
  
  }}}} // namespace boost::gil::test::fixture
  
  #endif
  