ceph/src/boost/libs/geometry/include/boost/geometry/strategies/concepts/area_concept.hpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2
   3 // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
   4 // Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
   5 // Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
   6
   7 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
   8 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
   9
  10 // Use, modification and distribution is subject to the Boost Software License,
  11 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  12 // http://www.boost.org/LICENSE_1_0.txt)
  13
  14 #ifndef BOOST_GEOMETRY_STRATEGIES_CONCEPTS_AREA_CONCEPT_HPP
  15 #define BOOST_GEOMETRY_STRATEGIES_CONCEPTS_AREA_CONCEPT_HPP
  16
  17
  18 #include <boost/concept_check.hpp>
  19
  20
  21 namespace boost { namespace geometry { namespace concepts
  22 {
  23
  24
  25 /*!
  26     \brief Checks strategy for area
  27     \ingroup area
  28 */
  29 template <typename Strategy>
  30 class AreaStrategy
  31 {
  32 #ifndef DOXYGEN_NO_CONCEPT_MEMBERS
  33
  34     // 1) must define state_type,
  35     typedef typename Strategy::state_type state_type;
  36
  37     // 2) must define return_type,
  38     typedef typename Strategy::return_type return_type;
  39
  40     // 3) must define point_type, of polygon (segments)
  41     typedef typename Strategy::segment_point_type spoint_type;
  42
  43     struct check_methods
  44     {
  45         static void apply()
  46         {
  47             Strategy const* str = 0;
  48             state_type *st = 0;
  49
  50             // 4) must implement a method apply with the following signature
  51             spoint_type const* sp = 0;
  52             str->apply(*sp, *sp, *st);
  53
  54             // 5) must implement a static method result with the following signature
  55             return_type r = str->result(*st);
  56
  57             boost::ignore_unused_variable_warning(r);
  58             boost::ignore_unused_variable_warning(str);
  59         }
  60     };
  61
  62 public :
  63     BOOST_CONCEPT_USAGE(AreaStrategy)
  64     {
  65         check_methods::apply();
  66     }
  67
  68 #endif
  69 };
  70
  71
  72 }}} // namespace boost::geometry::concepts
  73
  74
  75 #endif // BOOST_GEOMETRY_STRATEGIES_CONCEPTS_AREA_CONCEPT_HPP