mapnik/include/mapnik/markers_converter.hpp
2008-02-05 13:57:40 +00:00

166 lines
5.2 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2006 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
*
*****************************************************************************/
//$Id$
#ifndef MARKERS_CONVERTER_HPP
#define MARKERS_CONVERTER_HPP
#include "agg_basics.h"
#include "agg_trans_affine.h"
#include <boost/utility.hpp>
namespace mapnik {
template <typename Locator, typename Shape, typename Detector>
class markers_converter : boost::noncopyable
{
public:
markers_converter(Locator & locator,Shape & shape, Detector & detector);
void rewind(unsigned path_id);
unsigned vertex(double * x, double * y);
private:
enum status_e
{
initial,
markers,
polygon,
stop
};
Locator & locator_;
Shape & shape_;
Detector & detector_;
status_e status_;
agg::trans_affine transform_;
agg::trans_affine mtx_;
unsigned num_markers_;
unsigned marker_;
};
template <typename Locator,typename Shape,typename Detector>
markers_converter<Locator,Shape,Detector>::markers_converter(Locator & locator,Shape & shape,
Detector & detector)
: locator_(locator),
shape_(shape),
detector_(detector),
status_(initial),
num_markers_(1),
marker_(0) {}
template <typename Locator, typename Shape,typename Detector>
void markers_converter<Locator,Shape,Detector>::rewind(unsigned path_id)
{
status_ = initial;
marker_ = 0;
num_markers_ = 1;
}
template <typename Locator, typename Shape, typename Detector>
unsigned markers_converter<Locator,Shape,Detector>::vertex( double * x, double * y)
{
unsigned cmd = agg::path_cmd_move_to;
double x1, y1, x2, y2;
while (!agg::is_stop(cmd))
{
switch (status_)
{
case initial:
if (num_markers_ == 0 )
{
cmd = agg::path_cmd_stop;
break;
}
locator_.rewind(marker_++);
status_ = markers;
num_markers_ = 0;
break;
case markers:
{
unsigned cmd1;
while (agg::is_move_to(cmd1 = locator_.vertex(&x1,&y1)));
if (agg::is_stop(cmd1))
{
status_ = stop;
break;
}
unsigned cmd2 = locator_.vertex(&x2,&y2);
if (agg::is_stop(cmd2))
{
status_ = stop;
break;
}
++num_markers_;
double dx = x2 - x1;
double dy = y2 - y1;
double d = ::sqrt(dx * dx + dy * dy);
Envelope<double> ext = shape_.extent();
if (d > ext.width())
{
mtx_ = transform_;
mtx_ *= agg::trans_affine_rotation(::atan2(dy,dx));
double marker_x = x1 + dx * 0.5;
double marker_y = y1 + dy * 0.5;
mtx_ *= agg::trans_affine_translation(marker_x,marker_y);
double minx = ext.minx();
double miny = ext.miny();
double maxx = ext.maxx();
double maxy = ext.maxy();
mtx_.transform(&minx,&miny);
mtx_.transform(&maxx,&maxy);
Envelope<double> e0(minx,miny,maxx,maxy);
if (detector_.has_placement(e0))
{
shape_.rewind(0);
status_ = polygon;
detector_.insert(ext);
}
}
break;
}
case polygon:
cmd = shape_.vertex(x,y);
if (agg::is_stop(cmd))
{
cmd = agg::path_cmd_move_to;
status_ = markers;
break;
}
mtx_.transform(x,y);
return cmd;
case stop:
cmd = agg::path_cmd_stop;
break;
}
}
return cmd;
}
}
#endif // MARKERS_CONVERTER_HPP