[/============================================================================
  Boost.Geometry (aka GGL, Generic Geometry Library)

  Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
  Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
  Copyright (c) 2009-2012 Mateusz Loskot, London, UK.

  Use, modification and distribution is 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)
=============================================================================/]

The __adaptor__ takes over the model of the original geometry, which might be:

* a linestring
* a ring
* a multi_point
* a multi_linestring
* a multi_polygon
