Edit: /usr/include/boost/gil/packed_pixel.hpp (9214B)
//
// 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_PACKED_PIXEL_HPP
#define BOOST_GIL_PACKED_PIXEL_HPP
#include
#include
#include
#include
namespace boost { namespace gil {
/// A model of a heterogeneous pixel whose channels are bit ranges.
/// For example 16-bit RGB in '565' format.
/// \defgroup ColorBaseModelPackedPixel packed_pixel
/// \ingroup ColorBaseModel
/// \brief A heterogeneous color base whose elements are reference proxies to channels in a pixel. Models ColorBaseValueConcept. This class is used to model packed pixels, such as 16-bit packed RGB.
/// \defgroup PixelModelPackedPixel packed_pixel
/// \ingroup PixelModel
/// \brief A heterogeneous pixel used to represent packed pixels with non-byte-aligned channels. Models PixelValueConcept
///
/// Example:
/// \code
/// using rgb565_pixel_t = packed_pixel_type, rgb_layout_t>::type;
/// static_assert(sizeof(rgb565_pixel_t) == 2, "");
///
/// rgb565_pixel_t r565;
/// get_color(r565,red_t()) = 31;
/// get_color(r565,green_t()) = 63;
/// get_color(r565,blue_t()) = 31;
/// assert(r565 == rgb565_pixel_t((uint16_t)0xFFFF));
/// \endcode
/// \ingroup ColorBaseModelPackedPixel PixelModelPackedPixel PixelBasedModel
/// \brief Heterogeneous pixel value whose channel references can be constructed from the pixel bitfield and their index. Models ColorBaseValueConcept, PixelValueConcept, PixelBasedConcept
/// Typical use for this is a model of a packed pixel (like 565 RGB)
/// \tparam BitField Type that holds the bits of the pixel. Typically an integral type, like std::uint16_t.
/// \tparam ChannelRefs MP11 list whose elements are packed channels. They must be constructible from BitField. GIL uses packed_channel_reference
/// \tparam Layout defining the color space and ordering of the channels. Example value: rgb_layout_t
template
struct packed_pixel
{
BitField _bitfield{0}; // TODO: Make private
using layout_t = Layout;
using value_type = packed_pixel;
using reference = value_type&;
using const_reference = value_type const&;
static constexpr bool is_mutable =
channel_traits>::is_mutable;
packed_pixel() = default;
explicit packed_pixel(const BitField& bitfield) : _bitfield(bitfield) {}
// Construct from another compatible pixel type
packed_pixel(const packed_pixel& p) : _bitfield(p._bitfield) {}
template
packed_pixel(Pixel const& p,
typename std::enable_if::value>::type* /*dummy*/ = nullptr)
{
check_compatible();
static_copy(p, *this);
}
packed_pixel(int chan0, int chan1)
: _bitfield(0)
{
static_assert(num_channels::value == 2, "");
gil::at_c<0>(*this) = chan0;
gil::at_c<1>(*this) = chan1;
}
packed_pixel(int chan0, int chan1, int chan2)
: _bitfield(0)
{
static_assert(num_channels::value == 3, "");
gil::at_c<0>(*this) = chan0;
gil::at_c<1>(*this) = chan1;
gil::at_c<2>(*this) = chan2;
}
packed_pixel(int chan0, int chan1, int chan2, int chan3)
: _bitfield(0)
{
static_assert(num_channels::value == 4, "");
gil::at_c<0>(*this) = chan0;
gil::at_c<1>(*this) = chan1;
gil::at_c<2>(*this) = chan2;
gil::at_c<3>(*this) = chan3;
}
packed_pixel(int chan0, int chan1, int chan2, int chan3, int chan4)
: _bitfield(0)
{
static_assert(num_channels::value == 5, "");
gil::at_c<0>(*this) = chan0;
gil::at_c<1>(*this) = chan1;
gil::at_c<2>(*this) = chan2;
gil::at_c<3>(*this) = chan3;
gil::at_c<4>(*this) = chan4;
}
auto operator=(packed_pixel const& p) -> packed_pixel&
{
_bitfield = p._bitfield;
return *this;
}
template
auto operator=(Pixel const& p) -> packed_pixel&
{
assign(p, is_pixel());
return *this;
}
template
bool operator==(Pixel const& p) const
{
return equal(p, is_pixel());
}
template
bool operator!=(Pixel const& p) const { return !(*this==p); }
private:
template
static void check_compatible()
{
gil_function_requires>();
}
template
void assign(Pixel const& p, std::true_type)
{
check_compatible();
static_copy(p, *this);
}
template
bool equal(Pixel const& p, std::true_type) const
{
check_compatible();
return static_equal(*this, p);
}
// Support for assignment/equality comparison of a channel with a grayscale pixel
static void check_gray()
{
static_assert(std::is_same::value, "");
}
template
void assign(Channel const& channel, std::false_type)
{
check_gray();
gil::at_c<0>(*this) = channel;
}
template
bool equal (Channel const& channel, std::false_type) const
{
check_gray();
return gil::at_c<0>(*this) == channel;
}
public:
auto operator=(int channel) -> packed_pixel&
{
check_gray();
gil::at_c<0>(*this) = channel;
return *this;
}
bool operator==(int channel) const
{
check_gray();
return gil::at_c<0>(*this) == channel;
}
};
/////////////////////////////
// ColorBasedConcept
/////////////////////////////
template
struct kth_element_type, K>
{
using type = typename channel_traits>::value_type;
};
template
struct kth_element_reference_type, K>
{
using type = typename channel_traits>::reference;
};
template
struct kth_element_const_reference_type, K>
{
using type = typename channel_traits>::const_reference;
};
template
inline
auto at_c(packed_pixel& p)
-> typename kth_element_reference_type, K>::type
{
return typename kth_element_reference_type
<
packed_pixel,
K
>::type{&p._bitfield};
}
template
inline
auto at_c(const packed_pixel& p)
-> typename kth_element_const_reference_type, K>::type
{
return typename kth_element_const_reference_type
<
packed_pixel,
K>::type{&p._bitfield};
}
/////////////////////////////
// PixelConcept
/////////////////////////////
// Metafunction predicate that flags packed_pixel as a model of PixelConcept.
// Required by PixelConcept
template
struct is_pixel> : std::true_type {};
/////////////////////////////
// PixelBasedConcept
/////////////////////////////
template
struct color_space_type>
{
using type = typename Layout::color_space_t;
};
template
struct channel_mapping_type>
{
using type = typename Layout::channel_mapping_t;
};
template
struct is_planar> : std::false_type {};
////////////////////////////////////////////////////////////////////////////////
/// Support for interleaved iterators over packed pixel
////////////////////////////////////////////////////////////////////////////////
/// \defgroup PixelIteratorModelPackedInterleavedPtr Pointer to packed_pixel
/// \ingroup PixelIteratorModel
/// \brief Iterators over interleaved pixels.
/// The pointer packed_pixel* is used as an iterator over interleaved
/// pixels of packed format.
/// Models PixelIteratorConcept, HasDynamicXStepTypeConcept, MemoryBasedIteratorConcept
template
struct iterator_is_mutable*>
: std::integral_constant::is_mutable>
{};
template
struct iterator_is_mutable*> : std::false_type {};
}} // namespace boost::gil
#endif