Imported Upstream version 1.49.0upstream/1.49.0

1 files changed, 156 insertions, 0 deletions

diff --git a/boost/gil/pixel_iterator.hpp b/boost/gil/pixel_iterator.hpp
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+/*
+    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_PIXEL_ITERATOR_H
+#define GIL_PIXEL_ITERATOR_H
+
+////////////////////////////////////////////////////////////////////////////////////////
+/// \file               
+/// \brief pixel iterator support
+/// \author Lubomir Bourdev and Hailin Jin \n
+///         Adobe Systems Incorporated
+/// \date   2005-2007 \n May 16, 2006
+///
+////////////////////////////////////////////////////////////////////////////////////////
+
+#include <cassert>
+#include <iterator>
+#include "gil_config.hpp"
+#include "gil_concept.hpp"
+#include "utilities.hpp"
+#include "pixel.hpp"
+
+namespace boost { namespace gil {
+
+//forwarded declaration (as this file is included in step_iterator.hpp)
+template <typename Iterator>
+class memory_based_step_iterator;
+
+template <typename Iterator> struct dynamic_x_step_type;
+
+/// \brief metafunction predicate determining whether the given iterator is a plain one or an adaptor over another iterator.
+/// Examples of adaptors are the step iterator and the dereference iterator adaptor.
+template <typename It>
+struct is_iterator_adaptor : public mpl::false_{};
+
+/// \brief returns the base iterator for a given iterator adaptor. Provide an specialization when introducing new iterator adaptors
+template <typename It>
+struct iterator_adaptor_get_base;
+
+/// \brief Changes the base iterator of an iterator adaptor. Provide an specialization when introducing new iterator adaptors
+template <typename It, typename NewBaseIt>
+struct iterator_adaptor_rebind;
+
+/// \brief Returns the type of an iterator just like the input iterator, except operating over immutable values
+template <typename It>
+struct const_iterator_type;
+
+// The default implementation when the iterator is a C pointer is to use the standard constness semantics
+template <typename T> struct const_iterator_type<      T*> { typedef const T* type; };
+template <typename T> struct const_iterator_type<const T*> { typedef const T* type; };
+
+/// \brief Metafunction predicate returning whether the given iterator allows for changing its values
+/// \ingroup GILIsMutable
+template <typename It>
+struct iterator_is_mutable{};
+
+// The default implementation when the iterator is a C pointer is to use the standard constness semantics
+template <typename T> struct iterator_is_mutable<      T*> : public mpl::true_{};
+template <typename T> struct iterator_is_mutable<const T*> : public mpl::false_{};
+
+/// \defgroup PixelIteratorModelInterleavedPtr C pointer to a pixel
+/// \ingroup PixelIteratorModel
+/// \brief Iterators over interleaved pixels.
+/// A C pointer to a model of PixelValueConcept is used as an iterator over interleaved pixels. Models PixelIteratorConcept, HomogeneousPixelBasedConcept, HasDynamicXStepTypeConcept, MemoryBasedIteratorConcept
+
+
+
+/////////////////////////////
+//  HasDynamicXStepTypeConcept
+/////////////////////////////
+
+/// \ingroup PixelIteratorModelInterleavedPtr 
+template <typename Pixel>
+struct dynamic_x_step_type<Pixel*> {
+    typedef memory_based_step_iterator<Pixel*> type;
+};
+
+/// \ingroup PixelIteratorModelInterleavedPtr 
+template <typename Pixel>
+struct dynamic_x_step_type<const Pixel*> {
+    typedef memory_based_step_iterator<const Pixel*> type;
+};
+
+
+/////////////////////////////
+//  PixelBasedConcept
+/////////////////////////////
+
+template <typename Pixel> struct color_space_type<      Pixel*> : public color_space_type<Pixel> {};
+template <typename Pixel> struct color_space_type<const Pixel*> : public color_space_type<Pixel> {};
+
+template <typename Pixel> struct channel_mapping_type<      Pixel*> : public channel_mapping_type<Pixel> {};
+template <typename Pixel> struct channel_mapping_type<const Pixel*> : public channel_mapping_type<Pixel> {};
+
+template <typename Pixel> struct is_planar<      Pixel*> : public is_planar<Pixel> {};
+template <typename Pixel> struct is_planar<const Pixel*> : public is_planar<Pixel> {};
+
+/////////////////////////////
+//  HomogeneousPixelBasedConcept
+/////////////////////////////
+
+template <typename Pixel> struct channel_type<Pixel*> : public channel_type<Pixel> {};
+template <typename Pixel> struct channel_type<const Pixel*> : public channel_type<Pixel> {};
+
+////////////////////////////////////////////////////////////////////////////////////////
+///
+/// Support for pixel iterator movement measured in memory units (bytes or bits) as opposed to pixel type. \n
+/// Necessary to handle image row alignment and channel plane alignment.
+///
+////////////////////////////////////////////////////////////////////////////////////////
+
+/////////////////////////////
+//  MemoryBasedIteratorConcept
+/////////////////////////////
+
+template <typename T>
+struct byte_to_memunit : public mpl::int_<1> {};
+
+template <typename P>
+inline std::ptrdiff_t memunit_step(const P*) { return sizeof(P); }
+
+template <typename P>
+inline std::ptrdiff_t memunit_distance(const P* p1, const P* p2) { 
+    return (gil_reinterpret_cast_c<const unsigned char*>(p2)-gil_reinterpret_cast_c<const unsigned char*>(p1)); 
+}
+
+template <typename P>
+inline void memunit_advance(P* &p, std::ptrdiff_t diff) { 
+    p=(P*)((unsigned char*)(p)+diff);
+}
+
+template <typename P>
+inline P* memunit_advanced(const P* p, std::ptrdiff_t diff) {
+    return (P*)((char*)(p)+diff);
+}
+
+//  memunit_advanced_ref
+//  (shortcut to advancing a pointer by a given number of memunits and taking the reference in case the compiler is not smart enough)
+
+template <typename P>
+inline P& memunit_advanced_ref(P* p, std::ptrdiff_t diff) {
+    return *memunit_advanced(p,diff);
+}
+
+} }  // namespace boost::gil
+
+#endif