101 lines
2.6 KiB
C++
101 lines
2.6 KiB
C++
// Boost.Geometry (aka GGL, Generic Geometry Library)
|
|
//
|
|
// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
|
|
// Use, modification and distribution is subject to the Boost Software License,
|
|
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
|
// http://www.boost.org/LICENSE_1_0.txt)
|
|
|
|
// SOCI example
|
|
|
|
// b: using WKT to retrieve points
|
|
|
|
// To build and run this example, see comments in example a
|
|
|
|
#include <soci.h>
|
|
#include <soci-postgresql.h>
|
|
|
|
#include <boost/algorithm/string.hpp>
|
|
#include <boost/optional.hpp>
|
|
#include <boost/timer.hpp>
|
|
#include <boost/random.hpp>
|
|
#include <boost/tuple/tuple.hpp>
|
|
|
|
#include <iostream>
|
|
#include <istream>
|
|
#include <ostream>
|
|
#include <sstream>
|
|
#include <string>
|
|
#include <exception>
|
|
|
|
#include <boost/geometry/geometry.hpp>
|
|
#include <boost/geometry/geometries/geometries.hpp>
|
|
|
|
#include <boost/geometry/io/wkt/wkt.hpp>
|
|
|
|
|
|
struct city
|
|
{
|
|
boost::geometry::model::point<float, 2, boost::geometry::cs::geographic<boost::geometry::degree> > location;
|
|
std::string name;
|
|
};
|
|
|
|
namespace soci
|
|
{
|
|
template <>
|
|
struct type_conversion<city>
|
|
{
|
|
typedef soci::values base_type;
|
|
|
|
static void from_base(const base_type& v, soci::indicator ind, city& value)
|
|
{
|
|
try
|
|
{
|
|
value.name = v.get<std::string>("name");
|
|
boost::geometry::read_wkt(v.get<std::string>("wkt"), value.location);
|
|
}
|
|
catch(const std::exception& e)
|
|
{
|
|
std::cout << e.what() << std::endl;
|
|
}
|
|
}
|
|
|
|
static void to_base(const city& value, base_type& v, soci::indicator& ind)
|
|
{
|
|
v.set("name", value.name);
|
|
std::ostringstream out;
|
|
out << boost::geometry::wkt(value.location);
|
|
v.set("wkt", out.str());
|
|
ind = i_ok;
|
|
}
|
|
};
|
|
}
|
|
|
|
int main()
|
|
{
|
|
try
|
|
{
|
|
soci::session sql(soci::postgresql, "dbname=ggl user=ggl password=ggl");
|
|
|
|
|
|
typedef std::vector<city> V;
|
|
|
|
soci::rowset<city> rows = sql.prepare << "select name,astext(location) as wkt from cities";
|
|
V vec;
|
|
std::copy(rows.begin(), rows.end(), std::back_inserter(vec));
|
|
|
|
for (V::const_iterator it = vec.begin(); it != vec.end(); ++it)
|
|
{
|
|
static const double sqrkm = 1000.0 * 1000.0;
|
|
std::cout << it->name
|
|
<< " " << boost::geometry::dsv(it->location)
|
|
//<< " " << boost::geometry::area(it->shape) / sqrkm << " km2"
|
|
<< std::endl;
|
|
}
|
|
}
|
|
catch (std::exception const &e)
|
|
{
|
|
std::cerr << "Error: " << e.what() << '\n';
|
|
}
|
|
return 0;
|
|
}
|