99 lines
3.7 KiB
C++
99 lines
3.7 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/feature.hpp>
|
|
#include <mapnik/feature_factory.hpp>
|
|
#include <mapnik/json/geometry_grammar_impl.hpp>
|
|
#include <mapnik/json/feature_grammar_impl.hpp>
|
|
// boost
|
|
#include <boost/spirit/include/support_multi_pass.hpp>
|
|
#include <boost/spirit/home/support/iterators/detail/functor_input_policy.hpp>
|
|
// stl
|
|
#include <string>
|
|
#include <vector>
|
|
#include <deque>
|
|
|
|
#include "large_geojson_featureset.hpp"
|
|
|
|
//namespace {
|
|
//using base_iterator_type = std::string::const_iterator;
|
|
//const mapnik::transcoder tr("utf8");
|
|
//const mapnik::json::feature_collection_grammar<base_iterator_type,mapnik::feature_impl> fc_grammar(tr);
|
|
//}
|
|
|
|
large_geojson_featureset::large_geojson_featureset(std::string const& filename,
|
|
array_type && index_array)
|
|
: file_(filename, std::ios::binary),
|
|
index_array_(std::move(index_array)),
|
|
index_itr_(index_array_.begin()),
|
|
index_end_(index_array_.end()),
|
|
ctx_(std::make_shared<mapnik::context_type>())
|
|
{
|
|
if (!file_) throw std::runtime_error("Can't open " + filename);
|
|
}
|
|
|
|
large_geojson_featureset::~large_geojson_featureset() {}
|
|
|
|
mapnik::feature_ptr large_geojson_featureset::next()
|
|
{
|
|
if (index_itr_ != index_end_)
|
|
{
|
|
#if BOOST_VERSION >= 105600
|
|
large_geojson_datasource::item_type const& item = *index_itr_++;
|
|
std::size_t file_offset = item.second;
|
|
//std::cerr << file_offset << " -- " << item.first << std::endl;
|
|
#else
|
|
std::size_t index = *index_itr_++;
|
|
#endif
|
|
|
|
using base_iterator_type = std::istreambuf_iterator<char>;
|
|
|
|
using chr_iterator_type =
|
|
boost::spirit::multi_pass
|
|
< base_iterator_type
|
|
, boost::spirit::iterator_policies::default_policy
|
|
< boost::spirit::iterator_policies::first_owner//ref_counted
|
|
, boost::spirit::iterator_policies::no_check
|
|
//, boost::spirit::iterator_policies::functor_input
|
|
//, boost::spirit::iterator_policies::split_std_deque
|
|
>
|
|
> ;
|
|
|
|
file_.seekg(file_offset);
|
|
base_iterator_type in(file_);
|
|
chr_iterator_type start(in);
|
|
chr_iterator_type end;
|
|
|
|
static const mapnik::transcoder tr("utf8");
|
|
static const mapnik::json::feature_grammar<chr_iterator_type,mapnik::feature_impl> grammar(tr);
|
|
using namespace boost::spirit;
|
|
standard_wide::space_type space;
|
|
mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_,1));
|
|
if (!qi::phrase_parse(start, end, (grammar)(boost::phoenix::ref(*feature)), space))
|
|
{
|
|
throw std::runtime_error("Failed to parse geojson feature");
|
|
}
|
|
return feature;
|
|
}
|
|
return mapnik::feature_ptr();
|
|
}
|