Codechange: refactor FindClosestDepot to not use pointers, but return a struct

src/aircraft.h

@@ -110,7 +110,7 @@ struct Aircraft FINAL : public SpecializedVehicle<Aircraft, VEH_AIRCRAFT> {
 	void OnNewDay();
 	uint Crash(bool flooded = false);
 	TileIndex GetOrderStationLocation(StationID station);
-	bool FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse);
+	ClosestDepot FindClosestDepot();
 
 	/**
 	 * Check if the aircraft type is a normal flying device; eg

src/aircraft_cmd.cpp

@@ -388,7 +388,7 @@ CommandCost CmdBuildAircraft(DoCommandFlag flags, TileIndex tile, const Engine *
 }
 
 
-bool Aircraft::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
+ClosestDepot Aircraft::FindClosestDepot()
 {
 	const Station *st = GetTargetAirportIfValid(this);
 	/* If the station is not a valid airport or if it has no hangars */
@@ -396,15 +396,12 @@ bool Aircraft::FindClosestDepot(TileIndex *location, DestinationID *destination,
 		/* the aircraft has to search for a hangar on its own */
 		StationID station = FindNearestHangar(this);
 
-		if (station == INVALID_STATION) return false;
+		if (station == INVALID_STATION) return ClosestDepot();
 
 		st = Station::Get(station);
 	}
 
-	if (location    != nullptr) *location    = st->xy;
+	return ClosestDepot(st->xy, st->index);
-	if (destination != nullptr) *destination = st->index;
-
-	return true;
 }
 
 static void CheckIfAircraftNeedsService(Aircraft *v)

src/order_cmd.cpp

@@ -1982,23 +1982,21 @@ bool UpdateOrderDest(Vehicle *v, const Order *order, int conditional_depth, bool
 
 			if (v->current_order.GetDepotActionType() & ODATFB_NEAREST_DEPOT) {
 				/* We need to search for the nearest depot (hangar). */
-				TileIndex location;
+				ClosestDepot closestDepot = v->FindClosestDepot();
-				DestinationID destination;
-				bool reverse;
 
-				if (v->FindClosestDepot(&location, &destination, &reverse)) {
+				if (closestDepot.found) {
 					/* PBS reservations cannot reverse */
-					if (pbs_look_ahead && reverse) return false;
+					if (pbs_look_ahead && closestDepot.reverse) return false;
 
-					v->SetDestTile(location);
+					v->SetDestTile(closestDepot.location);
-					v->current_order.SetDestination(destination);
+					v->current_order.SetDestination(closestDepot.destination);
 
 					/* If there is no depot in front, reverse automatically (trains only) */
-					if (v->type == VEH_TRAIN && reverse) Command<CMD_REVERSE_TRAIN_DIRECTION>::Do(DC_EXEC, v->index, false);
+					if (v->type == VEH_TRAIN && closestDepot.reverse) Command<CMD_REVERSE_TRAIN_DIRECTION>::Do(DC_EXEC, v->index, false);
 
 					if (v->type == VEH_AIRCRAFT) {
 						Aircraft *a = Aircraft::From(v);
-						if (a->state == FLYING && a->targetairport != destination) {
+						if (a->state == FLYING && a->targetairport != closestDepot.destination) {
 							/* The aircraft is now heading for a different hangar than the next in the orders */
 							extern void AircraftNextAirportPos_and_Order(Aircraft *a);
 							AircraftNextAirportPos_and_Order(a);

src/roadveh.h

@@ -139,7 +139,7 @@ struct RoadVehicle FINAL : public GroundVehicle<RoadVehicle, VEH_ROAD> {
 	uint Crash(bool flooded = false) override;
 	Trackdir GetVehicleTrackdir() const override;
 	TileIndex GetOrderStationLocation(StationID station) override;
-	bool FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse) override;
+	ClosestDepot FindClosestDepot() override;
 
 	bool IsBus() const;
 

src/roadveh_cmd.cpp

@@ -346,15 +346,12 @@ static FindDepotData FindClosestRoadDepot(const RoadVehicle *v, int max_distance
 	}
 }
 
-bool RoadVehicle::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
+ClosestDepot RoadVehicle::FindClosestDepot()
 {
 	FindDepotData rfdd = FindClosestRoadDepot(this, 0);
-	if (rfdd.best_length == UINT_MAX) return false;
+	if (rfdd.best_length == UINT_MAX) return ClosestDepot();
 
-	if (location    != nullptr) *location    = rfdd.tile;
+	return ClosestDepot(rfdd.tile, GetDepotIndex(rfdd.tile));
-	if (destination != nullptr) *destination = GetDepotIndex(rfdd.tile);
-
-	return true;
 }
 
 /**

src/saveload/afterload.cpp

@@ -3185,17 +3185,15 @@ bool AfterLoadGame()
 			TileIndex cur_tile = rv->tile;
 			if (!IsLevelCrossingTile(cur_tile)) continue;
 
-			TileIndex location;
+			ClosestDepot closestDepot = rv->FindClosestDepot();
-			DestinationID destination;
-			bool reverse = true;
 
 			/* Try to find a depot with a distance limit of 512 tiles (Manhattan distance). */
-			if (rv->FindClosestDepot(&location, &destination, &reverse) && DistanceManhattan(rv->tile, location) < 512u) {
+			if (closestDepot.found && DistanceManhattan(rv->tile, closestDepot.location) < 512u) {
 				/* Teleport all parts of articulated vehicles. */
 				for (RoadVehicle *u = rv; u != nullptr; u = u->Next()) {
-					u->tile = location;
+					u->tile = closestDepot.location;
-					int x = TileX(location) * TILE_SIZE + TILE_SIZE / 2;
+					int x = TileX(closestDepot.location) * TILE_SIZE + TILE_SIZE / 2;
-					int y = TileY(location) * TILE_SIZE + TILE_SIZE / 2;
+					int y = TileY(closestDepot.location) * TILE_SIZE + TILE_SIZE / 2;
 					u->x_pos = x;
 					u->y_pos = y;
 					u->z_pos = GetSlopePixelZ(x, y);

src/ship.h

@@ -35,24 +35,24 @@ struct Ship FINAL : public SpecializedVehicle<Ship, VEH_SHIP> {
 	/** We want to 'destruct' the right class. */
 	virtual ~Ship() { this->PreDestructor(); }
 
-	void MarkDirty();
+	void MarkDirty() override;
-	void UpdateDeltaXY();
+	void UpdateDeltaXY() override;
-	ExpensesType GetExpenseType(bool income) const { return income ? EXPENSES_SHIP_REVENUE : EXPENSES_SHIP_RUN; }
+	ExpensesType GetExpenseType(bool income) const override { return income ? EXPENSES_SHIP_REVENUE : EXPENSES_SHIP_RUN; }
-	void PlayLeaveStationSound(bool force = false) const;
+	void PlayLeaveStationSound(bool force = false) const override;
-	bool IsPrimaryVehicle() const { return true; }
+	bool IsPrimaryVehicle() const override { return true; }
-	void GetImage(Direction direction, EngineImageType image_type, VehicleSpriteSeq *result) const;
+	void GetImage(Direction direction, EngineImageType image_type, VehicleSpriteSeq *result) const override;
-	int GetDisplaySpeed() const { return this->cur_speed / 2; }
+	int GetDisplaySpeed() const override { return this->cur_speed / 2; }
-	int GetDisplayMaxSpeed() const { return this->vcache.cached_max_speed / 2; }
+	int GetDisplayMaxSpeed() const override { return this->vcache.cached_max_speed / 2; }
-	int GetCurrentMaxSpeed() const { return std::min<int>(this->vcache.cached_max_speed, this->current_order.GetMaxSpeed() * 2); }
+	int GetCurrentMaxSpeed() const override { return std::min<int>(this->vcache.cached_max_speed, this->current_order.GetMaxSpeed() * 2); }
-	Money GetRunningCost() const;
+	Money GetRunningCost() const override;
-	bool IsInDepot() const { return this->state == TRACK_BIT_DEPOT; }
+	bool IsInDepot() const override { return this->state == TRACK_BIT_DEPOT; }
-	bool Tick();
+	bool Tick() override;
-	void OnNewDay();
+	void OnNewDay() override;
-	Trackdir GetVehicleTrackdir() const;
+	Trackdir GetVehicleTrackdir() const override;
-	TileIndex GetOrderStationLocation(StationID station);
+	TileIndex GetOrderStationLocation(StationID station) override;
-	bool FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse);
+	ClosestDepot FindClosestDepot() override;
 	void UpdateCache();
-	void SetDestTile(TileIndex tile);
+	void SetDestTile(TileIndex tile) override;
 };
 
 bool IsShipDestinationTile(TileIndex tile, StationID station);

src/ship_cmd.cpp

@@ -913,14 +913,10 @@ CommandCost CmdBuildShip(DoCommandFlag flags, TileIndex tile, const Engine *e, V
 	return CommandCost();
 }
 
-bool Ship::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
+ClosestDepot Ship::FindClosestDepot()
 {
 	const Depot *depot = FindClosestShipDepot(this, 0);
+	if (depot == nullptr) return ClosestDepot();
 
-	if (depot == nullptr) return false;
+	return ClosestDepot(depot->xy, depot->index);
-
-	if (location    != nullptr) *location    = depot->xy;
-	if (destination != nullptr) *destination = depot->index;
-
-	return true;
 }

src/train.h

@@ -124,7 +124,7 @@ struct Train FINAL : public GroundVehicle<Train, VEH_TRAIN> {
 	uint Crash(bool flooded = false) override;
 	Trackdir GetVehicleTrackdir() const override;
 	TileIndex GetOrderStationLocation(StationID station) override;
-	bool FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse) override;
+	ClosestDepot FindClosestDepot() override;
 
 	void ReserveTrackUnderConsist() const;
 

src/train_cmd.cpp

@@ -2106,23 +2106,12 @@ static FindDepotData FindClosestTrainDepot(Train *v, int max_distance)
 	}
 }
 
-/**
+ClosestDepot Train::FindClosestDepot()
- * Locate the closest depot for this consist, and return the information to the caller.
- * @param[out] location    If not \c nullptr and a depot is found, store its location in the given address.
- * @param[out] destination If not \c nullptr and a depot is found, store its index in the given address.
- * @param[out] reverse     If not \c nullptr and a depot is found, store reversal information in the given address.
- * @return A depot has been found.
- */
-bool Train::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
 {
 	FindDepotData tfdd = FindClosestTrainDepot(this, 0);
-	if (tfdd.best_length == UINT_MAX) return false;
+	if (tfdd.best_length == UINT_MAX) return ClosestDepot();
 
-	if (location    != nullptr) *location    = tfdd.tile;
+	return ClosestDepot(tfdd.tile, GetDepotIndex(tfdd.tile), tfdd.reverse);
-	if (destination != nullptr) *destination = GetDepotIndex(tfdd.tile);
-	if (reverse     != nullptr) *reverse     = tfdd.reverse;
-
-	return true;
 }
 
 /** Play a sound for a train leaving the station. */

src/vehicle.cpp

@@ -2423,11 +2423,9 @@ CommandCost Vehicle::SendToDepot(DoCommandFlag flags, DepotCommand command)
 		return CommandCost();
 	}
 
-	TileIndex location;
+	ClosestDepot closestDepot = this->FindClosestDepot();
-	DestinationID destination;
-	bool reverse;
 	static const StringID no_depot[] = {STR_ERROR_UNABLE_TO_FIND_ROUTE_TO, STR_ERROR_UNABLE_TO_FIND_LOCAL_DEPOT, STR_ERROR_UNABLE_TO_FIND_LOCAL_DEPOT, STR_ERROR_CAN_T_SEND_AIRCRAFT_TO_HANGAR};
-	if (!this->FindClosestDepot(&location, &destination, &reverse)) return_cmd_error(no_depot[this->type]);
+	if (!closestDepot.found) return_cmd_error(no_depot[this->type]);
 
 	if (flags & DC_EXEC) {
 		if (this->current_order.IsType(OT_LOADING)) this->LeaveStation();
@@ -2437,19 +2435,19 @@ CommandCost Vehicle::SendToDepot(DoCommandFlag flags, DepotCommand command)
 			SetBit(gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS);
 		}
 
-		this->SetDestTile(location);
+		this->SetDestTile(closestDepot.location);
-		this->current_order.MakeGoToDepot(destination, ODTF_MANUAL);
+		this->current_order.MakeGoToDepot(closestDepot.destination, ODTF_MANUAL);
 		if ((command & DepotCommand::Service) == DepotCommand::None) this->current_order.SetDepotActionType(ODATFB_HALT);
 		SetWindowWidgetDirty(WC_VEHICLE_VIEW, this->index, WID_VV_START_STOP);
 
 		/* If there is no depot in front and the train is not already reversing, reverse automatically (trains only) */
-		if (this->type == VEH_TRAIN && (reverse ^ HasBit(Train::From(this)->flags, VRF_REVERSING))) {
+		if (this->type == VEH_TRAIN && (closestDepot.reverse ^ HasBit(Train::From(this)->flags, VRF_REVERSING))) {
 			Command<CMD_REVERSE_TRAIN_DIRECTION>::Do(DC_EXEC, this->index, false);
 		}
 
 		if (this->type == VEH_AIRCRAFT) {
 			Aircraft *a = Aircraft::From(this);
-			if (a->state == FLYING && a->targetairport != destination) {
+			if (a->state == FLYING && a->targetairport != closestDepot.destination) {
 				/* The aircraft is now heading for a different hangar than the next in the orders */
 				extern void AircraftNextAirportPos_and_Order(Aircraft *a);
 				AircraftNextAirportPos_and_Order(a);

src/vehicle_base.h

@@ -220,6 +220,23 @@ struct RefitDesc {
 			cargo(cargo), capacity(capacity), remaining(remaining) {}
 };
 
+/**
+ * Structure to return information about the closest depot location,
+ * and whether it could be found.
+ */
+struct ClosestDepot {
+	TileIndex location;
+	DestinationID destination; ///< The DestinationID as used for orders.
+	bool reverse;
+	bool found;
+
+	ClosestDepot() :
+		location(INVALID_TILE), destination(0), reverse(false), found(false) {}
+
+	ClosestDepot(TileIndex location, DestinationID destination, bool reverse = false) :
+		location(location), destination(destination), reverse(reverse), found(true) {}
+};
+
 /** %Vehicle data structure. */
 struct Vehicle : VehiclePool::PoolItem<&_vehicle_pool>, BaseVehicle, BaseConsist {
 private:
@@ -771,12 +788,9 @@ public:
 	/**
 	 * Find the closest depot for this vehicle and tell us the location,
 	 * DestinationID and whether we should reverse.
-	 * @param location    where do we go to?
+	 * @return A structure with information about the closest depot, if found.
-	 * @param destination what hangar do we go to?
-	 * @param reverse     should the vehicle be reversed?
-	 * @return true if a depot could be found.
 	 */
-	virtual bool FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse) { return false; }
+	virtual ClosestDepot FindClosestDepot() { return {}; }
 
 	virtual void SetDestTile(TileIndex tile) { this->dest_tile = tile; }