spatial_rank.hpp

// -*- C++ -*-
//
// Copyright Sylvain Bougerel 2009 - 2013.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file COPYING or copy at
// http://www.boost.org/LICENSE_1_0.txt)

#ifndef SPATIAL_RANK_HPP
#define SPATIAL_RANK_HPP

#include "spatial_node.hpp" // for modulo()

namespace spatial
{
  namespace details
  {
    template <dimension_type Value>
    struct Static_rank
    {
      dimension_type operator()() const
      { return Value; }
    };

    struct Dynamic_rank
    {
      dimension_type operator()() const
      { return _rank; }

      explicit
      Dynamic_rank(dimension_type rank = 1)
        : _rank(rank)
      { }

    private:
      dimension_type _rank;
    };

    template<typename Rank>
    inline dimension_type
    incr_dim(Rank rank, dimension_type node_dim)
    { return (node_dim + 1) % rank(); }

    template<typename Rank>
    inline dimension_type
    decr_dim(Rank rank, dimension_type node_dim)
    { return (rank() + node_dim - 1) % rank(); }

    template <typename Link, typename Rank>
    inline dimension_type
    modulo(const Node<Link>* x, Rank r)
    {
      dimension_type d = r() - 1;
      while(!header(x)) { ++d; x = x->parent; }
      return d % r();
    }
  }
}

#endif // SPATIAL_RANK_HPP