mapnik/include/mapnik/geometry_to_path.hpp
2015-05-13 11:32:34 +01:00

166 lines
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_TO_PATH_HPP
#define MAPNIK_GEOMETRY_TO_PATH_HPP
#include <mapnik/geometry.hpp>
#include <mapnik/path.hpp>
namespace mapnik { namespace geometry { namespace detail {
//template <typename Transformer>
struct geometry_to_path
{
geometry_to_path(path_type & p)
: p_(p) {}
template <typename T>
void operator() (geometry<T> const& geom) const
{
mapnik::util::apply_visitor(*this, geom);
}
void operator() (geometry_empty const&) const
{
// no-op
}
// point
template <typename T>
void operator() (point<T> const& pt) const
{
//point pt_new;
//Transformer::apply(pt, pt_new);
p_.move_to(pt.x, pt.y);
}
// line_string
template <typename T>
void operator() (line_string<T> const& line) const
{
bool first = true;
for (auto const& pt : line)
{
//point pt_new;
//Transformer::apply(pt, pt_new);
if (first) { p_.move_to(pt.x, pt.y); first=false;}
else p_.line_to(pt.x, pt.y);
}
}
// polygon
template <typename T>
void operator() (polygon<T> const& poly) const
{
// exterior
bool first = true;
for (auto const& pt : poly.exterior_ring)
{
if (first)
{
p_.move_to(pt.x, pt.y);
first=false;
}
else
{
p_.line_to(pt.x, pt.y);
}
}
if (!first)
{
p_.close_path();
}
// interior
for (auto const& ring : poly.interior_rings)
{
first = true;
for (auto const& pt : ring)
{
if (first) {
p_.move_to(pt.x, pt.y);
first=false;
}
else
{
p_.line_to(pt.x, pt.y);
}
}
if (!first)
{
p_.close_path();
}
}
}
// multi point
template <typename T>
void operator() (multi_point<T> const& multi_pt) const
{
for (auto const& pt : multi_pt)
{
(*this)(pt);
}
}
// multi_line_string
template <typename T>
void operator() (multi_line_string<T> const& multi_line) const
{
for (auto const& line : multi_line)
{
(*this)(line);
}
}
// multi_polygon
template <typename T>
void operator() (multi_polygon<T> const& multi_poly) const
{
for (auto const& poly : multi_poly)
{
(*this)(poly);
}
}
template <typename T>
void operator() (geometry_collection<T> const& collection) const
{
for (auto const& geom : collection)
{
(*this)(geom);
}
}
path_type & p_;
};
} // ns detail
template <typename T>
void to_path(T const& geom, path_type & p)
{
detail::geometry_to_path func(p);
func(geom);
}
}}
#endif // MAPNIK_GEOMETRY_TO_PATH_HPP