EdgePath const getReachableTo(int to, bool clear_visited);
/// \return a vector of the reachable vertices, avoiding all "excludes"
EdgePath const getReachable(int from, bool only_viewable,
EdgePath const getReachableTo(int to, bool clear_visited);
/// \return a vector of the reachable vertices, avoiding all "excludes"
EdgePath const getReachable(int from, bool only_viewable,