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#ifndef FILE_DATASOURCE_HPP
#define FILE_DATASOURCE_HPP
// mapnik
#include <mapnik/datasource.hpp>
#include <mapnik/params.hpp>
#include <mapnik/query.hpp>
#include <mapnik/feature.hpp>
#include <mapnik/box2d.hpp>
#include <mapnik/coord.hpp>
#include <mapnik/feature_layer_desc.hpp>
// boost
#include <boost/optional.hpp>
#include <boost/shared_ptr.hpp>
// stl
#include <string>
class hello_datasource : public mapnik::datasource
{
public:
// constructor
// arguments must not change
hello_datasource(mapnik::parameters const& params);
// destructor
virtual ~hello_datasource ();
// mandatory: type of the plugin, used to match at runtime
mapnik::datasource::datasource_t type() const;
// mandatory: name of the plugin
static const char * name();
// mandatory: function to query features by box2d
// this is called when rendering, specifically in feature_style_processor.hpp
mapnik::featureset_ptr features(mapnik::query const& q) const;
// mandatory: function to query features by point (coord2d)
// not used by rendering, but available to calling applications
mapnik::featureset_ptr features_at_point(mapnik::coord2d const& pt, double tol = 0) const;
// mandatory: return the box2d of the datasource
// called during rendering to determine if the layer should be processed
mapnik::box2d<double> envelope() const;
// mandatory: optionally return the overal geometry type of the datasource
boost::optional<mapnik::datasource::geometry_t> get_geometry_type() const;
// mandatory: return the layer descriptor
mapnik::layer_descriptor get_descriptor() const;
private:
// recommended - do intialization in a so-named init function
// to reduce code in constructor
void init(mapnik::parameters const& params);
// recommended naming convention of datasource members:
// name_, type_, extent_, and desc_
static const std::string name_;
mapnik::layer_descriptor desc_;
mapnik::box2d<double> extent_;
};
#endif // FILE_DATASOURCE_HPP
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