mapnik/include/mapnik/geometry_remove_empty.hpp

77 lines
2.1 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_REMOVE_EMPTY_HPP
#define MAPNIK_GEOMETRY_REMOVE_EMPTY_HPP
#include <mapnik/geometry.hpp>
#include <mapnik/geometry_is_empty.hpp>
namespace mapnik { namespace geometry {
namespace detail {
struct geometry_remove_empty
{
mapnik::geometry::multi_line_string<double> operator() (mapnik::geometry::multi_line_string<double> const & geom) const
{
return remove_empty(geom);
}
mapnik::geometry::multi_polygon<double> operator() (mapnik::geometry::multi_polygon<double> const & geom) const
{
return remove_empty(geom);
}
template <typename T>
T operator() (T const & geom) const
{
return geom;
}
private:
template <typename T>
T remove_empty(T const & geom) const
{
T new_geom;
for (auto const & g : geom)
{
if (!g.empty())
{
new_geom.emplace_back(g);
}
}
return new_geom;
}
};
}
template <typename GeomType>
inline GeomType remove_empty(GeomType const& geom)
{
return detail::geometry_remove_empty()(geom);
}
}}
#endif // MAPNIK_GEOMETRY_REMOVE_EMPTY_HPP