mapnik/include/mapnik/markers_placement.hpp
2015-06-16 12:49:16 +02:00

109 lines
4.2 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_MARKERS_PLACEMENT_HPP
#define MAPNIK_MARKERS_PLACEMENT_HPP
#include <mapnik/markers_placements/line.hpp>
#include <mapnik/markers_placements/point.hpp>
#include <mapnik/markers_placements/interior.hpp>
#include <mapnik/markers_placements/vertext_first.hpp>
#include <mapnik/markers_placements/vertext_last.hpp>
#include <mapnik/symbolizer_enumerations.hpp>
#include <mapnik/util/variant.hpp>
namespace mapnik
{
template <typename Locator, typename Detector>
class markers_placement_finder : util::noncopyable
{
public:
using markers_placement = util::variant<markers_point_placement<Locator, Detector>,
markers_line_placement<Locator, Detector>,
markers_interior_placement<Locator, Detector>,
markers_vertex_first_placement<Locator, Detector>,
markers_vertex_last_placement<Locator, Detector>>;
class get_point_visitor
{
public:
get_point_visitor(double &x, double &y, double &angle, bool ignore_placement)
: x_(x), y_(y), angle_(angle), ignore_placement_(ignore_placement)
{
}
template <typename T>
bool operator()(T &placement) const
{
return placement.get_point(x_, y_, angle_, ignore_placement_);
}
private:
double &x_, &y_, &angle_;
bool ignore_placement_;
};
markers_placement_finder(marker_placement_e placement_type,
Locator &locator,
Detector &detector,
markers_placement_params const& params)
: placement_(create(placement_type, locator, detector, params))
{
}
// Get next point where the marker should be placed. Returns true if a place is found, false if none is found.
bool get_point(double &x, double &y, double &angle, bool ignore_placement)
{
return util::apply_visitor(get_point_visitor(x, y, angle, ignore_placement), placement_);
}
private:
// Factory function for particular placement implementations.
static markers_placement create(marker_placement_e placement_type,
Locator &locator,
Detector &detector,
markers_placement_params const& params)
{
switch (placement_type)
{
case MARKER_POINT_PLACEMENT:
return markers_point_placement<Locator, Detector>(locator,detector,params);
case MARKER_INTERIOR_PLACEMENT:
return markers_interior_placement<Locator, Detector>(locator,detector,params);
case MARKER_LINE_PLACEMENT:
return markers_line_placement<Locator, Detector>(locator,detector,params);
case MARKER_VERTEX_FIRST_PLACEMENT:
return markers_vertex_first_placement<Locator, Detector>(locator,detector,params);
case MARKER_VERTEX_LAST_PLACEMENT:
return markers_vertex_last_placement<Locator, Detector>(locator,detector,params);
default: // point
return markers_point_placement<Locator, Detector>(locator,detector,params);
}
}
markers_placement placement_;
};
}
#endif // MAPNIK_MARKERS_PLACEMENT_HPP