mapnik/include/mapnik/geometry_is_empty.hpp
2015-04-09 15:22:51 -05:00

92 lines
2.4 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2015 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
#ifndef MAPNIK_GEOMETRY_IS_EMPTY_HPP
#define MAPNIK_GEOMETRY_IS_EMPTY_HPP
#include <mapnik/geometry.hpp>
namespace mapnik { namespace geometry {
namespace detail {
struct geometry_is_empty
{
bool operator() (mapnik::geometry::geometry<double> const& geom) const
{
return mapnik::util::apply_visitor(*this, geom);
}
bool operator() (mapnik::geometry::point<double> const&) const
{
return false;
}
bool operator() (mapnik::geometry::line_string<double> const& geom) const
{
return geom.empty();
}
bool operator() (mapnik::geometry::polygon<double> const& geom) const
{
return geom.empty();
}
bool operator() (mapnik::geometry::multi_point<double> const& geom) const
{
return geom.empty();
}
bool operator() (mapnik::geometry::multi_line_string<double> const& geom) const
{
return geom.empty();
}
bool operator() (mapnik::geometry::multi_polygon<double> const& geom) const
{
return geom.empty();
}
bool operator() (mapnik::geometry::geometry_collection<double> const& geom) const
{
return geom.empty();
}
template <typename T>
bool operator() (T const& geom) const
{
return true;
}
};
}
template <typename GeomType>
inline bool is_empty(GeomType const& geom)
{
return detail::geometry_is_empty()(geom);
}
}}
#endif // MAPNIK_GEOMETRY_IS_EMPTY_HPP