mapnik/plugins/input/osm/osm_featureset.cpp

144 lines
5.3 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
*
*****************************************************************************/
#include <iostream>
#include "osm_featureset.hpp"
#include <mapnik/geometry.hpp>
using mapnik::Feature;
using mapnik::feature_ptr;
using mapnik::geometry_type;
using std::cerr;
using std::endl;
template <typename filterT>
osm_featureset<filterT>::osm_featureset(const filterT& filter,
osm_dataset * dataset,
const std::set<std::string>&
attribute_names,
std::string const& encoding)
: filter_(filter),
query_ext_(),
tr_(new transcoder(encoding)),
feature_id_(1),
dataset_ (dataset),
attribute_names_ (attribute_names)
{
dataset_->rewind();
}
template <typename filterT>
feature_ptr osm_featureset<filterT>::next()
{
osm_item * cur_item = dataset_->next_item();
feature_ptr feature;
bool success=false;
if(cur_item != NULL)
{
if(dataset_->current_item_is_node())
{
feature= feature_ptr(new Feature(feature_id_));
++feature_id_;
double lat = static_cast<osm_node*>(cur_item)->lat;
double lon = static_cast<osm_node*>(cur_item)->lon;
geometry_type * point = new geometry_type(mapnik::Point);
point->move_to(lon,lat);
feature->add_geometry(point);
success=true;
}
else if (dataset_->current_item_is_way())
{
bounds b = static_cast<osm_way*>(cur_item)->get_bounds();
// Loop until we find a feature which passes the filter
while(cur_item != NULL &&
!filter_.pass(box2d<double>(b.w,b.s,b.e,b.n)))
{
cur_item = dataset_->next_item();
if(cur_item!=NULL)
b = static_cast<osm_way*>(cur_item)->get_bounds();
}
if(cur_item != NULL)
{
if(static_cast<osm_way*>(cur_item)->nodes.size())
{
feature=feature_ptr(new Feature(feature_id_++));
++feature_id_;
geometry_type *geom;
if(static_cast<osm_way*>(cur_item)->is_polygon())
geom=new geometry_type(mapnik::Polygon);
else
geom=new geometry_type(mapnik::LineString);
geom->set_capacity(static_cast<osm_way*>(cur_item)->
nodes.size());
geom->move_to(static_cast<osm_way*>(cur_item)->
nodes[0]->lon,
static_cast<osm_way*>(cur_item)->
nodes[0]->lat);
for(unsigned int count=1; count<static_cast<osm_way*>(cur_item)
->nodes.size(); count++)
{
geom->line_to(static_cast<osm_way*>(cur_item)
->nodes[count]->lon,
static_cast<osm_way*>(cur_item)
->nodes[count]->lat);
}
feature->add_geometry(geom);
success=true;
}
}
}
// can feature_ptr be compared to NULL? - no
if(success)
{
std::map<std::string,std::string>::iterator i=
cur_item->keyvals.begin();
// add the keyvals to the feature. the feature seems to be a map
// of some sort so this should work - see dbf_file::add_attribute()
while(i != cur_item->keyvals.end())
{
//only add if in the specified set of attribute names
if(attribute_names_.find(i->first) != attribute_names_.end())
(*feature)[i->first] = tr_->transcode(i->second.c_str());
i++;
}
return feature;
}
}
return feature_ptr();
}
template <typename filterT>
osm_featureset<filterT>::~osm_featureset() {}
template class osm_featureset<mapnik::filter_in_box>;
template class osm_featureset<mapnik::filter_at_point>;