diff options
| -rw-r--r-- | src/train_cmd.cpp | 123 |
1 files changed, 72 insertions, 51 deletions
diff --git a/src/train_cmd.cpp b/src/train_cmd.cpp index 51b77cee6..7bc7edb51 100644 --- a/src/train_cmd.cpp +++ b/src/train_cmd.cpp @@ -1085,6 +1085,71 @@ static void NormaliseTrainConsist(Train *v) } } +/** + * Check/validate the new train length + * @param dst_head The destination chain of the to be moved vehicle + * @param src_head The source chain of the to be moved vehicle + * @param src The to be moved vehicle + * @param move_chain Whether to move all vehicles after src or not + * @return possible error of this command. + */ +static CommandCost CheckNewTrainLength(const Train *dst_head, const Train *src_head, const Train *src, bool move_chain) +{ + /* Check if all vehicles in the source train are stopped inside a depot. */ + int src_len = CheckTrainStoppedInDepot(src_head); + if (src_len < 0) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT); + + /* Check if all vehicles in the destination train are stopped inside a depot. */ + int dst_len = dst_head != NULL ? CheckTrainStoppedInDepot(dst_head) : 0; + if (dst_len < 0) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT); + + /* Determine the maximum length of trains. */ + int max_len = _settings_game.vehicle.mammoth_trains ? 100 : 10; + + /* If the length of both the source and destination combined is + * within the maximum length for trains there is no need for any + * complex calculations. All and any combination of vehicles + * will be within the required lengths. */ + if (src_len + dst_len <= max_len) return CommandCost(); + + if (!move_chain && !src_head->IsFrontEngine() && src_head == src && (src_len - 1) > max_len) { + /* Moving of a *single* non-engine at the front of the chain, + * i.e. a free wagon list. If the next unit is an engine a new + * train will be created instead of removing a vehicle from a + * free chain. The newly created train may not be too long. */ + const Train *u = src_head->GetNextUnit(); + if (u != NULL && u->IsEngine()) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); + } + + /* If we're only moving within the train. The 'only' corner case that + * needs to be checked for this is that no new vehicle is created. + * This is done in above here. */ + if (src_head == dst_head) return CommandCost(); + + /* Going to make a new vehicle chain, but it is going to be a wagon + * chain or we are going to add vehicles to a free wagon chain. + * That chain does not have a limitation on its length. + * NOTE that this cannot be done earlier in case the first vehicle + * is removed from a free wagon chain and the second is an engine; + * the new train in the source chain needs to be checked. */ + if (dst_head == NULL ? !src->IsEngine() : !dst_head->IsFrontEngine()) { + return CommandCost(); + } + + /* We are moving between rows, so only count the wagons from the source + * row that are being moved. */ + if (move_chain) { + /* CheckTrainStoppedInDepot() counts units. */ + for (const Train *u = src_head; u != src && u != NULL; u = u->GetNextUnit()) src_len--; + } else { + /* If moving only one vehicle, just count that. */ + src_len = 1; + } + + if (src_len + dst_len > max_len) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); + return CommandCost(); +} + /** Move a rail vehicle around inside the depot. * @param tile unused * @param flags type of operation @@ -1145,58 +1210,14 @@ CommandCost CmdMoveRailVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, u /* when moving all wagons, we can't have the same src_head and dst_head */ if (HasBit(p2, 0) && src_head == dst_head) return CommandCost(); - /* check if all vehicles in the source train are stopped inside a depot. */ - int src_len = CheckTrainStoppedInDepot(src_head); - if (src_len < 0) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT); - if ((flags & DC_AUTOREPLACE) == 0) { - /* Check whether there are more than 'max_len' train units (articulated parts and rear heads do not count) in the new chain */ - int max_len = _settings_game.vehicle.mammoth_trains ? 100 : 10; - - /* check the destination row if the source and destination aren't the same. */ - if (src_head != dst_head) { - int dst_len = 0; - - if (dst_head != NULL) { - /* check if all vehicles in the dest train are stopped. */ - dst_len = CheckTrainStoppedInDepot(dst_head); - if (dst_len < 0) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT); - } - - if (src_head == src && !HasBit(p2, 0)) { - /* Moving of a *single* vehicle at the front of the train. - * If the next vehicle is an engine a new train will be created - * instead of removing a vehicle from a free chain. The newly - * created train may not be too long. */ - const Train *u = src_head->GetNextVehicle(); - if (u != NULL && u->IsEngine() && (src_len - 1) > max_len) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); - } - - /* We are moving between rows, so only count the wagons from the source - * row that are being moved. */ - if (HasBit(p2, 0)) { - const Train *u; - /* CheckTrainStoppedInDepot() does counts dual-headed engines only once, so also do it here */ - for (u = src_head; u != src && u != NULL; u = u->GetNextUnit()) { - src_len--; - } - } else { - /* If moving only one vehicle, just count that. */ - src_len = 1; - } - - if (src_len + dst_len > max_len) { - /* Abort if we're adding too many wagons to a train. */ - if (dst_head != NULL && dst_head->IsFrontEngine()) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); - /* Abort if we're making a train on a new row. */ - if (dst_head == NULL && src->IsEngine()) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); - } - } else { - /* Abort if we're creating a new train on an existing row. */ - if (src_len > max_len && src == src_head && src_head->GetNextVehicle()->IsEngine()) { - return_cmd_error(STR_ERROR_TRAIN_TOO_LONG); - } - } + /* If the autoreplace flag is set we already are sure about + * the fact that the vehicle is stopped. Autoreplace also + * cannot add more units to a chain. As such it will never + * create a too long vehicle and thus there is no need to + * do the length checks for autoreplace. */ + CommandCost ret = CheckNewTrainLength(dst_head, src_head, src, HasBit(p2, 0)); + if (ret.Failed()) return ret; } /* moving a loco to a new line?, then we need to assign a unitnumber. */ |