C++ CommandCost类代码示例

/**
 * Send all vehicles of type to depots
 * @param flags   the flags used for DoCommand()
 * @param service should the vehicles only get service in the depots
 * @param vli     identifier of the vehicle list
 * @return 0 for success and CMD_ERROR if no vehicle is able to go to depot
 */
static CommandCost SendAllVehiclesToDepot(DoCommandFlag flags, bool service, const VehicleListIdentifier &vli)
{
	VehicleList list;

	if (!GenerateVehicleSortList(&list, vli)) return CMD_ERROR;

	/* Send all the vehicles to a depot */
	bool had_success = false;
	for (uint i = 0; i < list.Length(); i++) {
		const Vehicle *v = list[i];
		CommandCost ret = DoCommand(v->tile, v->index | (service ? DEPOT_SERVICE : 0U) | DEPOT_DONT_CANCEL, 0, flags, GetCmdSendToDepot(vli.vtype));

		if (ret.Succeeded()) {
			had_success = true;

			/* Return 0 if DC_EXEC is not set this is a valid goto depot command)
			 * In this case we know that at least one vehicle can be sent to a depot
			 * and we will issue the command. We can now safely quit the loop, knowing
			 * it will succeed at least once. With DC_EXEC we really need to send them to the depot */
			if (!(flags & DC_EXEC)) break;
		}
	}

	return had_success ? CommandCost() : CMD_ERROR;
}

/**
 * Set the start date of the timetable.
 * @param tile Not used.
 * @param flags Operation to perform.
 * @param p1 Vehicle id.
 * @param p2 The timetable start date in ticks.
 */
CommandCost CmdSetTimetableStart(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	if (!_settings_game.order.timetabling) return CMD_ERROR;

	Vehicle *v = Vehicle::GetIfValid(GB(p1, 0, 16));
	if (v == NULL || !v->IsPrimaryVehicle()) return CMD_ERROR;

	CommandCost ret = CheckOwnership(v->owner);
	if (ret.Failed()) return ret;

	/* Don't let a timetable start more than 15 years into the future or 1 year in the past. */
	Date start_date = (Date)p2;
	if (start_date < 0 || start_date > MAX_DAY) return CMD_ERROR;
	if (start_date - _date > 15 * DAYS_IN_LEAP_YEAR) return CMD_ERROR;
	if (_date - start_date > DAYS_IN_LEAP_YEAR) return CMD_ERROR;

	if (flags & DC_EXEC) {
		v->lateness_counter = 0;
		ClrBit(v->vehicle_flags, VF_TIMETABLE_STARTED);
		v->timetable_start = start_date;

		SetWindowDirty(WC_VEHICLE_TIMETABLE, v->index);
	}

	return CommandCost();
}

/**
 * Remove a buoy
 * @param tile TileIndex been queried
 * @param flags operation to perform
 * @pre IsBuoyTile(tile)
 * @return cost or failure of operation
 */
CommandCost RemoveBuoy(TileIndex tile, DoCommandFlag flags)
{
	/* XXX: strange stuff, allow clearing as invalid company when clearing landscape */
	if (!Company::IsValidID(_current_company) && !(flags & DC_BANKRUPT)) return_cmd_error(INVALID_STRING_ID);

	Waypoint *wp = Waypoint::GetByTile(tile);

	if (HasStationInUse(wp->index, false, _current_company)) return_cmd_error(STR_ERROR_BUOY_IS_IN_USE);
	/* remove the buoy if there is a ship on tile when company goes bankrupt... */
	if (!(flags & DC_BANKRUPT)) {
		CommandCost ret = EnsureNoVehicleOnGround(tile);
		if (ret.Failed()) return ret;
	}

	if (flags & DC_EXEC) {
		wp->facilities &= ~FACIL_DOCK;

		InvalidateWindowData(WC_WAYPOINT_VIEW, wp->index);

		/* We have to set the water tile's state to the same state as before the
		 * buoy was placed. Otherwise one could plant a buoy on a canal edge,
		 * remove it and flood the land (if the canal edge is at level 0) */
		MakeWaterKeepingClass(tile, GetTileOwner(tile));

		wp->rect.AfterRemoveTile(wp, tile);

		wp->UpdateVirtCoord();
		wp->delete_ctr = 0;
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_WAYPOINT_BUOY]);
}

/**
 * Sells all vehicles in a depot
 * @param tile Tile of the depot where the depot is
 * @param flags type of operation
 * @param p1 Vehicle type
 * @param p2 unused
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdDepotSellAllVehicles(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	VehicleList list;

	CommandCost cost(EXPENSES_NEW_VEHICLES);
	VehicleType vehicle_type = Extract<VehicleType, 0, 3>(p1);

	if (!IsCompanyBuildableVehicleType(vehicle_type)) return CMD_ERROR;

	uint sell_command = GetCmdSellVeh(vehicle_type);

	/* Get the list of vehicles in the depot */
	BuildDepotVehicleList(vehicle_type, tile, &list, &list);

	CommandCost last_error = CMD_ERROR;
	bool had_success = false;
	for (uint i = 0; i < list.Length(); i++) {
		CommandCost ret = DoCommand(tile, list[i]->index | (1 << 20), 0, flags, sell_command);
		if (ret.Succeeded()) {
			cost.AddCost(ret);
			had_success = true;
		} else {
			last_error = ret;
		}
	}

	return had_success ? cost : last_error;
}

/**
 * Rename a waypoint.
 * @param tile unused
 * @param flags type of operation
 * @param p1 id of waypoint
 * @param p2 unused
 * @param text the new name or an empty string when resetting to the default
 * @return the cost of this operation or an error
 */
CommandCost CmdRenameWaypoint(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	Waypoint *wp = Waypoint::GetIfValid(p1);
	if (wp == NULL) return CMD_ERROR;

	if (wp->owner != OWNER_NONE) {
		CommandCost ret = CheckOwnership(wp->owner);
		if (ret.Failed()) return ret;
	}

	bool reset = StrEmpty(text);

	if (!reset) {
		if (Utf8StringLength(text) >= MAX_LENGTH_STATION_NAME_CHARS) return CMD_ERROR;
		if (!IsUniqueWaypointName(text)) return_cmd_error(STR_ERROR_NAME_MUST_BE_UNIQUE);
	}

	if (flags & DC_EXEC) {
		free(wp->name);
		wp->name = reset ? NULL : strdup(text);

		wp->UpdateVirtCoord();
	}
	return CommandCost();
}

static CommandCost RemoveShipDepot(TileIndex tile, DoCommandFlag flags)
{
	if (!IsShipDepot(tile)) return CMD_ERROR;

	CommandCost ret = CheckTileOwnership(tile);
	if (ret.Failed()) return ret;

	TileIndex tile2 = GetOtherShipDepotTile(tile);

	/* do not check for ship on tile when company goes bankrupt */
	if (!(flags & DC_BANKRUPT)) {
		CommandCost ret = EnsureNoVehicleOnGround(tile);
		if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile2);
		if (ret.Failed()) return ret;
	}

	if (flags & DC_EXEC) {
		delete Depot::GetByTile(tile);

		Company *c = Company::GetIfValid(GetTileOwner(tile));
		if (c != NULL) {
			c->infrastructure.water -= 2 * LOCK_DEPOT_TILE_FACTOR;
			DirtyCompanyInfrastructureWindows(c->index);
		}

		MakeWaterKeepingClass(tile,  GetTileOwner(tile));
		MakeWaterKeepingClass(tile2, GetTileOwner(tile2));
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_DEPOT_SHIP]);
}

static CommandCost RemoveShipDepot(TileIndex tile, DoCommandFlag flags)
{
	if (!IsShipDepot(tile)) return CMD_ERROR;

	CommandCost ret = CheckTileOwnership(tile);
	if (ret.Failed()) return ret;

	TileIndex tile2 = GetOtherShipDepotTile(tile);

	/* do not check for ship on tile when company goes bankrupt */
	if (!(flags & DC_BANKRUPT)) {
		CommandCost ret = EnsureNoVehicleOnGround(tile);
		if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile2);
		if (ret.Failed()) return ret;
	}

	if (flags & DC_EXEC) {
		delete Depot::GetByTile(tile);

		MakeWaterKeepingClass(tile,  GetTileOwner(tile));
		MakeWaterKeepingClass(tile2, GetTileOwner(tile2));
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_DEPOT_SHIP]);
}

/**
 * Rename a depot.
 * @param tile unused
 * @param flags type of operation
 * @param p1 id of depot
 * @param p2 unused
 * @param text the new name or an empty string when resetting to the default
 * @return the cost of this operation or an error
 */
CommandCost CmdRenameDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	Depot *d = Depot::GetIfValid(p1);
	if (d == NULL) return CMD_ERROR;

	CommandCost ret = CheckTileOwnership(d->xy);
	if (ret.Failed()) return ret;

	bool reset = StrEmpty(text);

	if (!reset) {
		if (Utf8StringLength(text) >= MAX_LENGTH_DEPOT_NAME_CHARS) return CMD_ERROR;
		if (!IsUniqueDepotName(text)) return_cmd_error(STR_ERROR_NAME_MUST_BE_UNIQUE);
	}

	if (flags & DC_EXEC) {
		free(d->name);

		if (reset) {
			d->name = NULL;
			MakeDefaultName(d);
		} else {
			d->name = strdup(text);
		}

		/* Update the orders and depot */
		SetWindowClassesDirty(WC_VEHICLE_ORDERS);
		SetWindowDirty(WC_VEHICLE_DEPOT, d->xy);

		/* Update the depot list */
		VehicleType vt = GetDepotVehicleType(d->xy);
		SetWindowDirty(GetWindowClassForVehicleType(vt), VehicleListIdentifier(VL_DEPOT_LIST, vt, GetTileOwner(d->xy), d->index).Pack());
	}
	return CommandCost();
}

/** Refits a ship to the specified cargo type.
 * @param tile unused
 * @param flags type of operation
 * @param p1 vehicle ID of the ship to refit
 * @param p2 various bitstuffed elements
 * - p2 = (bit 0-7) - the new cargo type to refit to (p2 & 0xFF)
 * - p2 = (bit 8-15) - the new cargo subtype to refit to
 * - p2 = (bit 16) - refit only this vehicle (ignored)
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdRefitShip(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	CargoID new_cid = GB(p2, 0, 8); // gets the cargo number
	byte new_subtype = GB(p2, 8, 8);

	Ship *v = Ship::GetIfValid(p1);
	if (v == NULL) return CMD_ERROR;

	CommandCost ret = CheckOwnership(v->owner);
	if (ret.Failed()) return ret;

	if (!v->IsStoppedInDepot()) return_cmd_error(STR_ERROR_SHIP_MUST_BE_STOPPED_IN_DEPOT);
	if (v->vehstatus & VS_CRASHED) return_cmd_error(STR_ERROR_CAN_T_REFIT_DESTROYED_VEHICLE);

	/* Check cargo */
	if (new_cid >= NUM_CARGO) return CMD_ERROR;

	CommandCost cost = RefitVehicle(v, true, new_cid, new_subtype, flags);

	if (flags & DC_EXEC) {
		v->colourmap = PAL_NONE; // invalidate vehicle colour map
		SetWindowDirty(WC_VEHICLE_DETAILS, v->index);
		SetWindowDirty(WC_VEHICLE_DEPOT, v->tile);
		InvalidateWindowClassesData(WC_SHIPS_LIST, 0);
	}
	v->InvalidateNewGRFCacheOfChain(); // always invalidate; querycost might have filled it

	return cost;

}

/**
 * Check whether the given tile is suitable for a waypoint.
 * @param tile the tile to check for suitability
 * @param axis the axis of the waypoint
 * @param waypoint Waypoint the waypoint to check for is already joined to. If we find another waypoint it can join to it will throw an error.
 */
static CommandCost IsValidTileForWaypoint(TileIndex tile, Axis axis, StationID *waypoint)
{
	/* if waypoint is set, then we have special handling to allow building on top of already existing waypoints.
	 * so waypoint points to INVALID_STATION if we can build on any waypoint.
	 * Or it points to a waypoint if we're only allowed to build on exactly that waypoint. */
	if (waypoint != NULL && IsTileType(tile, MP_STATION)) {
		if (!IsRailWaypoint(tile)) {
			return ClearTile_Station(tile, DC_AUTO); // get error message
		} else {
			StationID wp = GetStationIndex(tile);
			if (*waypoint == INVALID_STATION) {
				*waypoint = wp;
			} else if (*waypoint != wp) {
				return_cmd_error(STR_ERROR_WAYPOINT_ADJOINS_MORE_THAN_ONE_EXISTING);
			}
		}
	}

	if (GetAxisForNewWaypoint(tile) != axis) return_cmd_error(STR_ERROR_NO_SUITABLE_RAILROAD_TRACK);

	Owner owner = GetTileOwner(tile);
	CommandCost ret = CheckOwnership(owner);
	if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile);
	if (ret.Failed()) return ret;

	Slope tileh = GetTileSlope(tile);
	if (tileh != SLOPE_FLAT &&
			(!_settings_game.construction.build_on_slopes || IsSteepSlope(tileh) || !(tileh & (0x3 << axis)) || !(tileh & ~(0x3 << axis)))) {
		return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
	}

	if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);

	return CommandCost();
}

/**
 * Remove a lock.
 * @param tile Central tile of the lock.
 * @param flags Operation to perform.
 * @return The cost in case of success, or an error code if it failed.
 */
static CommandCost RemoveLock(TileIndex tile, DoCommandFlag flags)
{
	if (GetTileOwner(tile) != OWNER_NONE) {
		CommandCost ret = CheckTileOwnership(tile);
		if (ret.Failed()) return ret;
	}

	TileIndexDiff delta = TileOffsByDiagDir(GetLockDirection(tile));

	/* make sure no vehicle is on the tile. */
	CommandCost ret = EnsureNoVehicleOnGround(tile);
	if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile + delta);
	if (ret.Succeeded()) ret = EnsureNoVehicleOnGround(tile - delta);
	if (ret.Failed()) return ret;

	if (flags & DC_EXEC) {
		DoClearSquare(tile);
		MakeWaterKeepingClass(tile + delta, GetTileOwner(tile + delta));
		MakeWaterKeepingClass(tile - delta, GetTileOwner(tile - delta));
		MarkCanalsAndRiversAroundDirty(tile - delta);
		MarkCanalsAndRiversAroundDirty(tile + delta);
	}

	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_LOCK]);
}

/**
 * Change the service interval of a vehicle
 * @param tile unused
 * @param flags type of operation
 * @param p1 vehicle ID that is being service-interval-changed
 * @param p2 bitmask
 * - p2 = (bit  0-15) - new service interval
 * - p2 = (bit 16)    - service interval is custom flag
 * - p2 = (bit 17)    - service interval is percentage flag
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdChangeServiceInt(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	Vehicle *v = Vehicle::GetIfValid(p1);
	if (v == NULL || !v->IsPrimaryVehicle()) return CMD_ERROR;

	CommandCost ret = CheckOwnership(v->owner);
	if (ret.Failed()) return ret;

	const Company *company = Company::Get(v->owner);
	bool iscustom  = HasBit(p2, 16);
	bool ispercent = iscustom ? HasBit(p2, 17) : company->settings.vehicle.servint_ispercent;

	uint16 serv_int;
	if (iscustom) {
		serv_int = GB(p2, 0, 16);
		if (serv_int != GetServiceIntervalClamped(serv_int, ispercent)) return CMD_ERROR;
	} else {
		serv_int = CompanyServiceInterval(company, v->type);
	}

	if (flags & DC_EXEC) {
		v->SetServiceInterval(serv_int);
		v->SetServiceIntervalIsCustom(iscustom);
		v->SetServiceIntervalIsPercent(ispercent);
		SetWindowDirty(WC_VEHICLE_DETAILS, v->index);
	}

	return CommandCost();
}

/**
 * Copy head specific things to the new vehicle chain after it was successfully constructed
 * @param old_head The old front vehicle (no wagons attached anymore)
 * @param new_head The new head of the completely replaced vehicle chain
 * @param flags the command flags to use
 */
static CommandCost CopyHeadSpecificThings(Vehicle *old_head, Vehicle *new_head, DoCommandFlag flags)
{
	CommandCost cost = CommandCost();

	/* Share orders */
	if (cost.Succeeded() && old_head != new_head) cost.AddCost(DoCommand(0, new_head->index | CO_SHARE << 30, old_head->index, DC_EXEC, CMD_CLONE_ORDER));

	/* Copy group membership */
	if (cost.Succeeded() && old_head != new_head) cost.AddCost(DoCommand(0, old_head->group_id, new_head->index, DC_EXEC, CMD_ADD_VEHICLE_GROUP));

	/* Perform start/stop check whether the new vehicle suits newgrf restrictions etc. */
	if (cost.Succeeded()) {
		/* Start the vehicle, might be denied by certain things */
		assert((new_head->vehstatus & VS_STOPPED) != 0);
		cost.AddCost(CmdStartStopVehicle(new_head, true));

		/* Stop the vehicle again, but do not care about evil newgrfs allowing starting but not stopping :p */
		if (cost.Succeeded()) cost.AddCost(CmdStartStopVehicle(new_head, false));
	}

	/* Last do those things which do never fail (resp. we do not care about), but which are not undo-able */
	if (cost.Succeeded() && old_head != new_head && (flags & DC_EXEC) != 0) {
		/* Copy other things which cannot be copied by a command and which shall not stay resetted from the build vehicle command */
		new_head->CopyVehicleConfigAndStatistics(old_head);

		/* Switch vehicle windows/news to the new vehicle, so they are not closed/deleted when the old vehicle is sold */
		ChangeVehicleViewports(old_head->index, new_head->index);
		ChangeVehicleViewWindow(old_head->index, new_head->index);
		ChangeVehicleNews(old_head->index, new_head->index);
	}

	return cost;
}

/**
 * Build a buoy.
 * @param tile tile where to place the buoy
 * @param flags operation to perform
 * @param p1 unused
 * @param p2 unused
 * @param text unused
 * @return the cost of this operation or an error
 */
CommandCost CmdBuildBuoy(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	if (tile == 0) return_cmd_error(STR_ERROR_SITE_UNSUITABLE);

	WaterClass wc;
	if ((flags & DC_PASTE) && !(flags & DC_EXEC)) {
		/* When pasting a buoy, there may be no water yet (a canal will be placed when DC_EXE'ing).
		 * Ignore that there is no water so we can calculate the cost more precisely. */
		wc = WATER_CLASS_INVALID;
	} else {
		if (!HasTileWaterGround(tile)) return_cmd_error(STR_ERROR_SITE_UNSUITABLE);
		wc = GetWaterClass(tile);
	}

	if (IsBridgeAbove(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);

	if (!IsTileFlat(tile)) return_cmd_error(STR_ERROR_SITE_UNSUITABLE);

	/* Check if there is an already existing, deleted, waypoint close to us that we can reuse. */
	Waypoint *wp = FindDeletedWaypointCloseTo(tile, STR_SV_STNAME_BUOY, OWNER_NONE);
	if (wp == NULL && !Waypoint::CanAllocateItem()) return_cmd_error(STR_ERROR_TOO_MANY_STATIONS_LOADING);

	CommandCost cost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_WAYPOINT_BUOY]);
	if (!IsWaterTile(tile)) {
		CommandCost ret = DoCommand(tile, 0, 0, flags | DC_AUTO, CMD_LANDSCAPE_CLEAR);
		if (ret.Failed()) return ret;
		cost.AddCost(ret);
	}

	if (flags & DC_EXEC) {
		if (wp == NULL) {
			wp = new Waypoint(tile);
		} else {
			/* Move existing (recently deleted) buoy to the new location */
			wp->xy = tile;
			InvalidateWindowData(WC_WAYPOINT_VIEW, wp->index);
		}
		wp->rect.BeforeAddTile(tile, StationRect::ADD_TRY);

		wp->string_id = STR_SV_STNAME_BUOY;

		wp->facilities |= FACIL_DOCK;
		wp->owner = OWNER_NONE;

		wp->build_date = _date;

		if (wp->town == NULL) MakeDefaultName(wp);

		assert(wc != WATER_CLASS_INVALID);
		MakeBuoy(tile, wp->index, wc);

		wp->UpdateVirtCoord();
		InvalidateWindowData(WC_WAYPOINT_VIEW, wp->index);
	}

	return cost;
}

/**
 * Copy a piece of map and instantly paste at given location.
 *
 * @param tile Tile where to paste (northern).
 * @param flags Command flags.
 * @param p1 Various bits:
 *    \li bits  0..27 [28] - northern tile of the source area
 *    \li bits 28..31  [4] - rail type (RailType) to convert to, ignored if CPM_CONVERT_RAILTYPE mode is off
 * @param p2 Various bits:
 *    \li bits  0..5   [6] - source area width
 *    \li bits  6..11  [6] - source area height
 *    \li bits 12..15  [4] - additional amount of tile heights to add to each tile (-8..7)
 *    \li bits 16..18  [3] - transformation to perform (DirTransformation)
 *    \li bits 19..27  [9] - mode (CopyPasteMode)
 *    \li bits 28..31  [4] - [ unused ]
 * @param text Unused.
 * @return The cost of this operation or an error.
 */
CommandCost CmdInstantCopyPaste(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
{
	CopyPasteParams copy_paste;

	/* extract and validate source area */
	copy_paste.src_area.tile = GenericTileIndex(TileIndex(GB(p1, 0, 28)));
	copy_paste.src_area.w = GB(p2, 0, 6);
	copy_paste.src_area.h = GB(p2, 6, 6);
	CommandCost ret = ValParamCopyPasteArea(copy_paste.src_area);
	if (ret.Failed()) return ret;

	/* calculate and validate destination area */
	copy_paste.dst_area = TransformTileArea(copy_paste.src_area, GenericTileIndex(tile), copy_paste.transformation);
	ret = ValParamCopyPasteArea(copy_paste.dst_area);
	if (ret.Failed()) return ret;

	/* extract and validate copy/paste mode */
	copy_paste.mode = (CopyPasteMode)GB(p2, 19, 9);
	if (!ValParamCopyPasteMode(copy_paste.mode)) return CMD_ERROR;

	/* extract and validate rail type */
	copy_paste.railtype = (RailType)GB(p1, 28,  4);
	if (!ValParamRailtype(copy_paste.railtype)) return CMD_ERROR;

	/* extract transformation */
	copy_paste.transformation = (DirTransformation)GB(p2, 16,  3);

	/* extract the additional number of height units */
	int additional_height_delta = GB(p2, 12, 4); // this is a 4-bit SIGNED integer (-8..7)
	additional_height_delta |= -(additional_height_delta & (1 << 3)); // propagate the sign bit

	/* calculate the height */
	copy_paste.height_delta = CalcCopyPasteHeightDelta(copy_paste.src_area, copy_paste.dst_area, copy_paste.transformation, additional_height_delta);

	/* when copy and paste areas are too close each other, firstly
	 * copy to the clipboard and then from the clipboard to the map */
	if (CopyPasteAreasMayColide(copy_paste)) {
		Map *clipboard = GetClipboardBuffer(INSTANT_COPY_PASTE_BUFFER);
		/* Copy to a buffer, but only in the first stage of the command.
		 * In a single player game and also while we are a server, the first one is non-DC_EXEC
		 * stage (which is fallowed then by a DC_EXEC stage). When we are a client, there is only
		 * one stage which is either a single non-DC_EXEC stage (shift pressed), or a single DC_EXEC
		 * stage (command comming from the network). */
		if ((_networking && !_network_server) || !(flags & DC_EXEC)) {
			CopyToClipboard(clipboard, copy_paste.src_area);
		}
		/* paste from the clipboard */
		ret = PasteFromClipboard(clipboard, tile, flags, copy_paste.mode, copy_paste.transformation, copy_paste.railtype, additional_height_delta);
	} else {
		/* copy/paste directly */
		InitializePasting(flags, copy_paste);
		DoCopyPaste(copy_paste);
		ret = FinalizePasting();
	}
	return ret;
}