mapnik/include/mapnik/geometry_reprojection_impl.hpp
2015-04-10 10:55:30 -05:00

400 lines
10 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2014 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
*
*****************************************************************************/
// mapnik
#include <mapnik/geometry_reprojection.hpp>
#include <mapnik/geometry.hpp>
namespace mapnik {
namespace geometry {
namespace detail {
geometry_empty reproject_internal(geometry_empty const&, proj_transform const&, unsigned int &)
{
return geometry_empty();
}
template <typename T>
point<T> reproject_internal(point<T> const & p, proj_transform const& proj_trans, unsigned int & n_err)
{
point<T> new_p(p);
if (!proj_trans.forward(new_p))
{
++n_err;
}
return new_p;
}
template <typename T>
line_string<T> reproject_internal(line_string<T> const & ls, proj_transform const& proj_trans, unsigned int & n_err)
{
line_string<T> new_ls(ls);
unsigned int err = proj_trans.forward(new_ls);
if (err > 0)
{
n_err += err;
}
return new_ls;
}
template <typename T>
polygon<T> reproject_internal(polygon<T> const & poly, proj_transform const& proj_trans, unsigned int & n_err)
{
polygon<T> new_poly;
linear_ring<T> new_ext(poly.exterior_ring);
unsigned int err = proj_trans.forward(new_ext);
// If the exterior ring doesn't transform don't bother with the holes.
if (err > 0 || new_ext.empty())
{
n_err += err;
}
else
{
new_poly.set_exterior_ring(std::move(new_ext));
new_poly.interior_rings.reserve(poly.interior_rings.size());
for (auto const& lr : poly.interior_rings)
{
linear_ring<T> new_lr(lr);
err = proj_trans.forward(new_lr);
if (err > 0 || new_lr.empty())
{
n_err += err;
// If there is an error in interior ring drop
// it from polygon.
continue;
}
new_poly.add_hole(std::move(new_lr));
}
}
return new_poly;
}
template <typename T>
multi_point<T> reproject_internal(multi_point<T> const & mp, proj_transform const& proj_trans, unsigned int & n_err)
{
multi_point<T> new_mp;
if (proj_trans.is_known())
{
// If the projection is known we do them all at once because it is faster
// since we know that no point will fail reprojection
new_mp.assign(mp.begin(), mp.end());
proj_trans.forward(new_mp);
}
else
{
new_mp.reserve(mp.size());
for (auto const& p : mp)
{
point<T> new_p(p);
if (!proj_trans.forward(new_p))
{
++n_err;
}
else
{
new_mp.emplace_back(std::move(new_p));
}
}
}
return new_mp;
}
template <typename T>
multi_line_string<T> reproject_internal(multi_line_string<T> const & mls, proj_transform const& proj_trans, unsigned int & n_err)
{
multi_line_string<T> new_mls;
new_mls.reserve(mls.size());
for (auto const& ls : mls)
{
line_string<T> new_ls = reproject_internal(ls, proj_trans, n_err);
if (!new_ls.empty())
{
new_mls.emplace_back(std::move(new_ls));
}
}
return new_mls;
}
template <typename T>
multi_polygon<T> reproject_internal(multi_polygon<T> const & mpoly, proj_transform const& proj_trans, unsigned int & n_err)
{
multi_polygon<T> new_mpoly;
new_mpoly.reserve(mpoly.size());
for (auto const& poly : mpoly)
{
polygon<T> new_poly = reproject_internal(poly, proj_trans, n_err);
if (!new_poly.exterior_ring.empty())
{
new_mpoly.emplace_back(std::move(new_poly));
}
}
return new_mpoly;
}
template <typename T>
geometry_collection<T> reproject_internal(geometry_collection<T> const & c, proj_transform const& proj_trans, unsigned int & n_err)
{
geometry_collection<T> new_c;
new_c.reserve(c.size());
for (auto const& g : c)
{
geometry<T> new_g(std::move(reproject_copy(g, proj_trans, n_err)));
if (!new_g.template is<geometry_empty>())
{
new_c.emplace_back(std::move(new_g));
}
}
return new_c;
}
template <typename T>
struct geom_reproj_copy_visitor {
geom_reproj_copy_visitor(proj_transform const & proj_trans, unsigned int & n_err)
: proj_trans_(proj_trans),
n_err_(n_err) {}
geometry<T> operator() (geometry_empty const&)
{
return geometry_empty();
}
geometry<T> operator() (point<T> const& p)
{
geometry<T> geom; // default empty
unsigned int intial_err = n_err_;
point<T> new_p = reproject_internal(p, proj_trans_, n_err_);
if (n_err_ > intial_err) return geom;
geom = std::move(new_p);
return geom;
}
geometry<T> operator() (line_string<T> const& ls)
{
geometry<T> geom; // default empty
int intial_err = n_err_;
line_string<T> new_ls = reproject_internal(ls, proj_trans_, n_err_);
if (n_err_ > intial_err || new_ls.empty()) return geom;
geom = std::move(new_ls);
return geom;
}
geometry<T> operator() (polygon<T> const& poly)
{
geometry<T> geom; // default empty
polygon<T> new_poly = reproject_internal(poly, proj_trans_, n_err_);
if (new_poly.exterior_ring.empty()) return geom;
geom = std::move(new_poly);
return geom;
}
geometry<T> operator() (multi_point<T> const& mp)
{
geometry<T> geom; // default empty
multi_point<T> new_mp = reproject_internal(mp, proj_trans_, n_err_);
if (new_mp.empty()) return geom;
geom = std::move(new_mp);
return geom;
}
geometry<T> operator() (multi_line_string<T> const& mls)
{
geometry<T> geom; // default empty
multi_line_string<T> new_mls = reproject_internal(mls, proj_trans_, n_err_);
if (new_mls.empty()) return geom;
geom = std::move(new_mls);
return geom;
}
geometry<T> operator() (multi_polygon<T> const& mpoly)
{
geometry<T> geom; // default empty
multi_polygon<T> new_mpoly = reproject_internal(mpoly, proj_trans_, n_err_);
if (new_mpoly.empty()) return geom;
geom = std::move(new_mpoly);
return geom;
}
geometry<T> operator() (geometry_collection<T> const& c)
{
geometry<T> geom; // default empty
geometry_collection<T> new_c = reproject_internal(c, proj_trans_, n_err_);
if (new_c.empty()) return geom;
geom = std::move(new_c);
return geom;
}
private:
proj_transform const& proj_trans_;
unsigned int & n_err_;
};
} // end detail ns
template <typename T>
geometry<T> reproject_copy(geometry<T> const& geom, proj_transform const& proj_trans, unsigned int & n_err)
{
detail::geom_reproj_copy_visitor<T> visit(proj_trans, n_err);
return mapnik::util::apply_visitor(visit, geom);
}
template <typename T>
T reproject_copy(T const& geom, proj_transform const& proj_trans, unsigned int & n_err)
{
return detail::reproject_internal(geom, proj_trans, n_err);
}
template <typename T>
T reproject_copy(T const& geom, projection const& source, projection const& dest, unsigned int & n_err)
{
proj_transform proj_trans(source, dest);
return reproject_copy(geom, proj_trans, n_err);
}
namespace detail {
struct geom_reproj_visitor {
geom_reproj_visitor(proj_transform const & proj_trans)
: proj_trans_(proj_trans) {}
template <typename T>
bool operator() (geometry<T> & geom)
{
return mapnik::util::apply_visitor((*this), geom);
}
bool operator() (geometry_empty &) { return true; }
template <typename T>
bool operator() (point<T> & p)
{
if (!proj_trans_.forward(p))
{
return false;
}
return true;
}
template <typename T>
bool operator() (line_string<T> & ls)
{
if (proj_trans_.forward(ls) > 0)
{
return false;
}
return true;
}
template <typename T>
bool operator() (polygon<T> & poly)
{
if (proj_trans_.forward(poly.exterior_ring) > 0)
{
return false;
}
for (auto & lr : poly.interior_rings)
{
if (proj_trans_.forward(lr) > 0)
{
return false;
}
}
return true;
}
template <typename T>
bool operator() (multi_point<T> & mp)
{
return (*this) (static_cast<line_string<T> &>(mp));
}
template <typename T>
bool operator() (multi_line_string<T> & mls)
{
for (auto & ls : mls)
{
if (! (*this) (ls))
{
return false;
}
}
return true;
}
template <typename T>
bool operator() (multi_polygon<T> & mpoly)
{
for (auto & poly : mpoly)
{
if(! (*this)(poly))
{
return false;
}
}
return true;
}
template <typename T>
bool operator() (geometry_collection<T> & c)
{
for (auto & g : c)
{
if (! (*this)(g) )
{
return false;
}
}
return true;
}
private:
proj_transform const& proj_trans_;
};
} // end detail ns
template <typename T>
bool reproject(T & geom, proj_transform const& proj_trans)
{
detail::geom_reproj_visitor visit(proj_trans);
return visit(geom);
}
template <typename T>
bool reproject(T & geom, projection const& source, projection const& dest)
{
proj_transform proj_trans(source, dest);
detail::geom_reproj_visitor visit(proj_trans);
return visit(geom);
}
} // end geometry ns
} // end mapnik ns