+ std::string create_appearance(const R2C2::TrackAppearance &);
+ std::string create_point_data(const R2C2::Vector &);
+ std::string create_line_data(const R2C2::Vector &, const R2C2::Vector &);
+ std::string create_curve_data(const R2C2::Vector &, const R2C2::Vector &, const R2C2::Vector &, const R2C2::Vector &);
+ std::string create_track_type(const R2C2::TrackType &);
+ void save_track(const R2C2::Track &);