mapnik/include/mapnik/geometry_is_simple.hpp
2016-07-25 14:54:43 +02:00

149 lines
4.4 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_SIMPLE_HPP
#define MAPNIK_GEOMETRY_IS_SIMPLE_HPP
#include <boost/version.hpp>
// only Boost >= 1.56 contains the is_simple function
#if BOOST_VERSION >= 105600
#include <mapnik/geometry.hpp>
#include <mapnik/geometry_adapters.hpp>
#include <boost/geometry/algorithms/is_simple.hpp>
namespace mapnik { namespace geometry {
namespace detail {
struct geometry_is_simple : public util::static_visitor<bool>
{
using result_type = bool;
template <typename T>
result_type operator() (geometry<T> const& geom) const
{
return mapnik::util::apply_visitor(*this, geom);
}
result_type operator() (geometry_empty const& ) const
{
// An empty geometry has no anomalous geometric points, such as self intersection or self tangency.
// Therefore, we will return true
return true;
}
template <typename T>
result_type operator() (geometry_collection<T> const& collection) const
{
for (auto const& geom : collection)
{
if ( !(*this)(geom)) return false;
}
return true;
}
template <typename T>
result_type operator() (point<T> const& pt) const
{
return boost::geometry::is_simple(pt);
}
template <typename T>
result_type operator() (line_string<T> const& line) const
{
if (line.empty())
{
// Prevent an empty line_string from segfaulting in boost geometry 1.58
// once it is fixed this can be removed
// https://svn.boost.org/trac/boost/ticket/11709
return true;
}
return boost::geometry::is_simple(line);
}
template <typename T>
result_type operator() (polygon<T> const& poly) const
{
return boost::geometry::is_simple(poly);
}
template <typename T>
result_type operator() (multi_point<T> const& multi_pt) const
{
if (multi_pt.empty())
{
// This return is due to bug in boost geometry once it is fixed it can be removed
// https://svn.boost.org/trac/boost/ticket/11710
return true;
}
return boost::geometry::is_simple(multi_pt);
}
template <typename T>
result_type operator() (multi_line_string<T> const& multi_line) const
{
if (multi_line.empty())
{
// This return is due to bug in boost geometry once it is fixed it can be removed
// https://svn.boost.org/trac/boost/ticket/11710
return true;
}
for (auto const& line : multi_line)
{
if (!(*this)(line)) return false;
}
return true;
}
template <typename T>
result_type operator() (multi_polygon<T> const& multi_poly) const
{
if (multi_poly.empty())
{
// This return is due to bug in boost geometry once it is fixed it can be removed
// https://svn.boost.org/trac/boost/ticket/11710
return true;
}
for (auto const& poly : multi_poly)
{
if (!(*this)(poly)) return false;
}
return true;
}
};
}
template <typename T>
inline bool is_simple(T const& geom)
{
return detail::geometry_is_simple() (geom);
}
template <typename T>
inline bool is_simple(mapnik::geometry::geometry<T> const& geom)
{
return util::apply_visitor(detail::geometry_is_simple(), geom);
}
}}
#endif // BOOST_VERSION >= 1.56
#endif // MAPNIK_GEOMETRY_IS_SIMPLE_HPP