/* $Id$ */ /* * This file is part of OpenTTD. * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>. */ /** @file refresh.h Declaration of link refreshing utility. */ #ifndef REFRESH_H #define REFRESH_H #include "../cargo_type.h" #include "../vehicle_base.h" #include <vector> #include <map> #include <set> /** * Utility to refresh links a consist will visit. */ class LinkRefresher { public: static void Run(Vehicle *v, bool allow_merge = true, bool is_full_loading = false); protected: /** * Various flags about properties of the last examined link that might have * an influence on the next one. */ enum RefreshFlags { USE_NEXT, ///< There was a conditional jump. Try to use the given next order when looking for a new one. HAS_CARGO, ///< Consist could leave the last stop where it could interact with cargo carrying cargo (i.e. not an "unload all" + "no loading" order). WAS_REFIT, ///< Consist was refit since the last stop where it could interact with cargo. RESET_REFIT, ///< Consist had a chance to load since the last refit and the refit capacities can be reset. IN_AUTOREFIT, ///< Currently doing an autorefit loop. Ignore the first autorefit order. }; /** * Simulated cargo type and capacity for prediction of future links. */ struct RefitDesc { CargoID cargo; ///< Cargo type the vehicle will be carrying. uint16 capacity; ///< Capacity the vehicle will have. uint16 remaining; ///< Capacity remaining from before the previous refit. RefitDesc(CargoID cargo, uint16 capacity, uint16 remaining) : cargo(cargo), capacity(capacity), remaining(remaining) {} }; /** * A hop the refresh algorithm might evaluate. If the same hop is seen again * the evaluation is stopped. This of course is a fairly simple heuristic. * Sequences of refit orders can produce vehicles with all kinds of * different cargoes and remembering only one can lead to early termination * of the algorithm. However, as the order language is Turing complete, we * are facing the halting problem here. At some point we have to draw the * line. */ struct Hop { OrderID from; ///< Last order where vehicle could interact with cargo or absolute first order. OrderID to; ///< Next order to be processed. CargoID cargo; ///< Cargo the consist is probably carrying or CT_INVALID if unknown. /** * Default constructor should not be called but has to be visible for * usage in std::set. */ Hop() {NOT_REACHED();} /** * Real constructor, only use this one. * @param from First order of the hop. * @param to Second order of the hop. * @param cargo Cargo the consist is probably carrying when passing the hop. */ Hop(OrderID from, OrderID to, CargoID cargo) : from(from), to(to), cargo(cargo) {} bool operator<(const Hop &other) const; }; typedef std::vector<RefitDesc> RefitList; typedef std::set<Hop> HopSet; Vehicle *vehicle; ///< Vehicle for which the links should be refreshed. uint capacities[NUM_CARGO]; ///< Current added capacities per cargo ID in the consist. RefitList refit_capacities; ///< Current state of capacity remaining from previous refits versus overall capacity per vehicle in the consist. HopSet *seen_hops; ///< Hops already seen. If the same hop is seen twice we stop the algorithm. This is shared between all Refreshers of the same run. CargoID cargo; ///< Cargo given in last refit order. bool allow_merge; ///< If the refresher is allowed to merge or extend link graphs. bool is_full_loading; ///< If the vehicle is full loading. LinkRefresher(Vehicle *v, HopSet *seen_hops, bool allow_merge, bool is_full_loading); bool HandleRefit(CargoID refit_cargo); void ResetRefit(); void RefreshStats(const Order *cur, const Order *next); const Order *PredictNextOrder(const Order *cur, const Order *next, uint8 flags, uint num_hops = 0); void RefreshLinks(const Order *cur, const Order *next, uint8 flags, uint num_hops = 0); }; #endif /* REFRESH_H */