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Diffstat (limited to 'boost/geometry/srs/projections/impl/adjlon.hpp')
-rw-r--r-- | boost/geometry/srs/projections/impl/adjlon.hpp | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/boost/geometry/srs/projections/impl/adjlon.hpp b/boost/geometry/srs/projections/impl/adjlon.hpp new file mode 100644 index 0000000000..7f0c9ac4ca --- /dev/null +++ b/boost/geometry/srs/projections/impl/adjlon.hpp @@ -0,0 +1,70 @@ +// Boost.Geometry (aka GGL, Generic Geometry Library) +// This file is manually converted from PROJ4 + +// Copyright (c) 2008-2012 Barend Gehrels, Amsterdam, the Netherlands. + +// 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) + +// This file is converted from PROJ4, http://trac.osgeo.org/proj +// PROJ4 is originally written by Gerald Evenden (then of the USGS) +// PROJ4 is maintained by Frank Warmerdam +// PROJ4 is converted to Geometry Library by Barend Gehrels (Geodan, Amsterdam) + +// Original copyright notice: + +// Permission is hereby granted, free of charge, to any person obtaining a +// copy of this software and associated documentation files (the "Software"), +// to deal in the Software without restriction, including without limitation +// the rights to use, copy, modify, merge, publish, distribute, sublicense, +// and/or sell copies of the Software, and to permit persons to whom the +// Software is furnished to do so, subject to the following conditions: + +// The above copyright notice and this permission notice shall be included +// in all copies or substantial portions of the Software. + +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS +// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL +// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +// DEALINGS IN THE SOFTWARE. + +#ifndef BOOST_GEOMETRY_PROJECTIONS_IMPL_ADJLON_HPP +#define BOOST_GEOMETRY_PROJECTIONS_IMPL_ADJLON_HPP + +#include <boost/math/constants/constants.hpp> +#include <boost/geometry/util/math.hpp> + +namespace boost { namespace geometry { namespace projections +{ + +namespace detail +{ + +/* reduce argument to range +/- PI */ +template <typename T> +inline T adjlon (T lon) +{ + if (geometry::math::abs(lon) <= boost::math::constants::pi<T>()) + { + return lon; + } + + /* adjust to 0..2pi rad */ + lon += boost::math::constants::pi<T>(); + /* remove integral # of 'revolutions'*/ + lon -= boost::math::constants::two_pi<T>() * + std::floor(lon / boost::math::constants::two_pi<T>()); + /* adjust back to -pi..pi rad */ + lon -= boost::math::constants::pi<T>(); + + return lon; +} + +} // namespace detail +}}} // namespace boost::geometry::projections + +#endif // BOOST_GEOMETRY_PROJECTIONS_IMPL_ADJLON_HPP |