mapnik/include/mapnik/symbolizer_helpers.hpp

203 lines
7.4 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2012 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 SYMBOLIZER_HELPERS_HPP
#define SYMBOLIZER_HELPERS_HPP
//mapnik
#include <mapnik/text_symbolizer.hpp>
#include <mapnik/shield_symbolizer.hpp>
#include <mapnik/expression_evaluator.hpp>
#include <mapnik/feature.hpp>
#include <mapnik/marker.hpp>
#include <mapnik/marker_cache.hpp>
#include <mapnik/processed_text.hpp>
#include <mapnik/text_path.hpp>
//boost
#include <boost/shared_ptr.hpp>
namespace mapnik {
typedef boost::ptr_vector<text_path> placements_type;
template <typename DetectorT> class placement_finder;
/** Helper object that does all the TextSymbolizer placment finding
* work except actually rendering the object. */
template <typename FaceManagerT, typename DetectorT>
class text_symbolizer_helper
{
public:
text_symbolizer_helper(text_symbolizer const& sym,
Feature const& feature,
proj_transform const& prj_trans,
unsigned width,
unsigned height,
double scale_factor,
CoordTransform const& t,
FaceManagerT &font_manager,
DetectorT &detector,
box2d<double> const& query_extent)
: sym_(sym),
feature_(feature),
prj_trans_(prj_trans),
t_(t),
font_manager_(font_manager),
detector_(detector),
dims_(0, 0, width, height),
query_extent_(query_extent),
text_(font_manager, scale_factor),
angle_(0.0),
placement_valid_(false),
points_on_line_(false),
finder_()
{
initialize_geometries();
if (!geometries_to_process_.size()) return;
placement_ = sym_.get_placement_options()->get_placement_info(scale_factor);
next_placement();
initialize_points();
}
/** Return next placement.
* If no more placements are found returns null pointer.
*/
bool next();
/** Get current placement. next() has to be called before! */
placements_type const& placements() const;
protected:
bool next_point_placement();
bool next_line_placement();
bool next_line_placement_clipped();
bool next_placement();
void initialize_geometries();
void initialize_points();
//Input
text_symbolizer const& sym_;
Feature const& feature_;
proj_transform const& prj_trans_;
CoordTransform const& t_;
FaceManagerT & font_manager_;
DetectorT & detector_;
box2d<double> dims_;
box2d<double> const& query_extent_;
//Processing
processed_text text_;
/* Using list instead of vector, because we delete random elements and need iterators to stay valid. */
/** Remaining geometries to be processed. */
std::list<geometry_type*> geometries_to_process_;
/** Geometry currently being processed. */
std::list<geometry_type*>::iterator geo_itr_;
/** Remaining points to be processed. */
std::list<position> points_;
/** Point currently being processed. */
std::list<position>::iterator point_itr_;
/** Text rotation. */
double angle_;
/** Text + formatting. */
string_info *info_;
/** Did last call to next_placement return true? */
bool placement_valid_;
/** Use point placement. Otherwise line placement is used. */
bool point_placement_;
/** Place text at points on a line instead of following the line (used for ShieldSymbolizer) .*/
bool points_on_line_;
text_placement_info_ptr placement_;
boost::shared_ptr<placement_finder<DetectorT> > finder_;
};
template <typename FaceManagerT, typename DetectorT>
class shield_symbolizer_helper: public text_symbolizer_helper<FaceManagerT, DetectorT>
{
public:
shield_symbolizer_helper(shield_symbolizer const& sym,
Feature const& feature,
proj_transform const& prj_trans,
unsigned width,
unsigned height,
double scale_factor,
CoordTransform const &t,
FaceManagerT &font_manager,
DetectorT &detector,
box2d<double> const& query_extent) :
text_symbolizer_helper<FaceManagerT, DetectorT>(sym, feature, prj_trans, width, height, scale_factor, t, font_manager, detector, query_extent),
sym_(sym)
{
this->points_on_line_ = true;
init_marker();
}
box2d<double> const& get_marker_extent() const
{
return marker_ext_;
}
double get_marker_height() const
{
return marker_h_;
}
double get_marker_width() const
{
return marker_w_;
}
bool next();
pixel_position get_marker_position(text_path const& p);
marker & get_marker() const;
agg::trans_affine const& get_image_transform() const;
protected:
bool next_point_placement();
bool next_line_placement();
void init_marker();
shield_symbolizer const& sym_;
box2d<double> marker_ext_;
boost::optional<marker_ptr> marker_;
agg::trans_affine image_transform_;
double marker_w_;
double marker_h_;
double marker_x_;
double marker_y_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::geometries_to_process_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::placement_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::next_placement;
using text_symbolizer_helper<FaceManagerT, DetectorT>::info_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::geo_itr_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::point_itr_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::points_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::font_manager_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::feature_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::t_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::detector_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::dims_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::prj_trans_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::placement_valid_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::point_placement_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::angle_;
using text_symbolizer_helper<FaceManagerT, DetectorT>::finder_;
};
} //namespace
#endif // SYMBOLIZER_HELPERS_HPP