bool snap(Point &, float &) const;
void break_link(Track &);
void break_links();
const std::vector<Track *> &get_links() const { return links; }
Track *get_link(unsigned) const;
bool snap(Point &, float &) const;
void break_link(Track &);
void break_links();
const std::vector<Track *> &get_links() const { return links; }
Track *get_link(unsigned) const;