boost/graph/one_bit_color_map.hpp
// Copyright (C) 2005-2010 The Trustees of Indiana University.
// 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)
// Authors: Jeremiah Willcock
// Douglas Gregor
// Andrew Lumsdaine
// One bit per color property map (gray and black are the same, green is not
// supported)
#ifndef BOOST_ONE_BIT_COLOR_MAP_HPP
#define BOOST_ONE_BIT_COLOR_MAP_HPP
#include <boost/property_map/property_map.hpp>
#include <boost/graph/properties.hpp>
#include <boost/shared_array.hpp>
#include <boost/config.hpp>
#include <boost/assert.hpp>
#include <algorithm>
#include <limits>
namespace boost {
enum one_bit_color_type {
one_bit_white = 0,
one_bit_not_white = 1
};
template <>
struct color_traits<one_bit_color_type>
{
static one_bit_color_type white() { return one_bit_white; }
static one_bit_color_type gray() { return one_bit_not_white; }
static one_bit_color_type black() { return one_bit_not_white; }
};
template<typename IndexMap = identity_property_map>
struct one_bit_color_map
{
BOOST_STATIC_CONSTANT(int, bits_per_char = std::numeric_limits<unsigned char>::digits);
std::size_t n;
IndexMap index;
shared_array<unsigned char> data;
typedef typename property_traits<IndexMap>::key_type key_type;
typedef one_bit_color_type value_type;
typedef void reference;
typedef read_write_property_map_tag category;
explicit one_bit_color_map(std::size_t n, const IndexMap& index = IndexMap())
: n(n), index(index), data(new unsigned char[(n + bits_per_char - 1) / bits_per_char])
{
// Fill to white
std::fill(data.get(), data.get() + (n + bits_per_char - 1) / bits_per_char, 0);
}
};
template<typename IndexMap>
inline one_bit_color_type
get(const one_bit_color_map<IndexMap>& pm,
typename property_traits<IndexMap>::key_type key)
{
BOOST_STATIC_CONSTANT(int, bits_per_char = one_bit_color_map<IndexMap>::bits_per_char);
typename property_traits<IndexMap>::value_type i = get(pm.index, key);
BOOST_ASSERT ((std::size_t)i < pm.n);
return one_bit_color_type((pm.data.get()[i / bits_per_char] >> (i % bits_per_char)) & 1);
}
template<typename IndexMap>
inline void
put(const one_bit_color_map<IndexMap>& pm,
typename property_traits<IndexMap>::key_type key,
one_bit_color_type value)
{
BOOST_STATIC_CONSTANT(int, bits_per_char = one_bit_color_map<IndexMap>::bits_per_char);
typename property_traits<IndexMap>::value_type i = get(pm.index, key);
BOOST_ASSERT ((std::size_t)i < pm.n);
BOOST_ASSERT (value >= 0 && value < 2);
std::size_t byte_num = i / bits_per_char;
std::size_t bit_position = (i % bits_per_char);
pm.data.get()[byte_num] =
(unsigned char)
((pm.data.get()[byte_num] & ~(1 << bit_position))
| (value << bit_position));
}
template<typename IndexMap>
inline one_bit_color_map<IndexMap>
make_one_bit_color_map(std::size_t n, const IndexMap& index_map)
{
return one_bit_color_map<IndexMap>(n, index_map);
}
} // end namespace boost
#endif // BOOST_ONE_BIT_COLOR_MAP_HPP
#ifdef BOOST_GRAPH_USE_MPI
# include <boost/graph/distributed/one_bit_color_map.hpp>
#endif