static CommandCost RemoveLock(TileIndex tile, DoCommandFlag flags)

    CommandCost cost(EXPENSES_CONSTRUCTION);

        if (GetTileOwner(tile) != OWNER_NONE) {

        CommandCost ret = CheckTileOwnership(tile);

        if (ret.Failed()) return ret;

        if (GetWaterClass(tile) != WATER_CLASS_RIVER) cost.AddCost(_price[PR_CLEAR_CANAL]);

    }

 

    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) {

        /* Remove middle part from company infrastructure count. */

        Company *c = Company::GetIfValid(GetTileOwner(tile));

        if (c != NULL) {

            c->infrastructure.water -= 3 * LOCK_DEPOT_TILE_FACTOR; // three parts of the lock.

            DirtyCompanyInfrastructureWindows(c->index);

        }

 

        if (GetWaterClass(tile) == WATER_CLASS_RIVER) {

            MakeRiver(tile, Random());

        } else {

            if (c != NULL) {

                c->infrastructure.water--;

            }

            DoClearSquare(tile);

        }

        MakeWaterKeepingClass(tile + delta, GetTileOwner(tile + delta));

        MakeWaterKeepingClass(tile - delta, GetTileOwner(tile - delta));

        MarkCanalsAndRiversAroundDirty(tile);

        MarkCanalsAndRiversAroundDirty(tile - delta);

        MarkCanalsAndRiversAroundDirty(tile + delta);

    }

 

    return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_LOCK]);