Here is a list of all documented struct and union fields with links to the struct/union documentation for each field:

### - u -

- undelivered_supply : Node
- UnfocusFocusedWidget() : Window
- Uninitialize() : Game , AI
- unique_id : ContentInfo
- unitnumber : Vehicle
- unitnumber_digits : BaseVehicleListWindow
- units : LocaleSettings
- units_volume : CargoSpec
- UnmappedChoiceList() : UnmappedChoiceList
- Unpack() : VehicleListIdentifier
- Unreserve() : VehicleCargoList
- UnreserveSingleTrack() : CYapfReserveTrack< Types >
- unsatisfied_demand : Edge
- Unselect() : ClientNetworkContentSocketHandler
- UnselectAll() : ClientNetworkContentSocketHandler
- UNSELECTED : ContentInfo
- UnselectVehicle() : VehicleGroupWindow
- UNSET : GRFTempEngineData
- unshaded_size : Window
- unwanted : Town
- Update() : Backup< T > , CargoDataEntry
- update_frequency : ServerNetworkAdminSocketHandler
- UpdateAcceleration() : Train
- UpdateAfterLoad() : GroupStatistics
- UpdateAutoRefitState() : OrdersWindow
- UpdateAutoreplace() : GroupStatistics
- UpdateCache() : Ship
- UpdateDeltaXY() : RoadVehicle , Ship , Train , Vehicle , DisasterVehicle , Aircraft , EffectVehicle
- UpdateInclination() : GroundVehicle< T, Type >
- UpdateNewGRFScanStatus() : ScanProgressWindow
- UpdateOptionWidgetStatus() : BuildRoadToolbarWindow
- UpdateOrderTimetable() : OrderList
- UpdateOskState() : OskWindow
- UpdateOverlayCargoes() : LinkGraphLegendWindow
- UpdateOverlayCompanies() : LinkGraphLegendWindow
- UpdatePalette() : CocoaSubdriver
- UpdatePosition() : ViewportSign , Scrollbar
- UpdateProfits() : GroupStatistics
- UpdateRealOrderIndex() : Vehicle
- UpdateRefittability() : GRFTempEngineData
- UpdateSelectionStates() : TimetableWindow
- UpdateSpeed() : RoadVehicle , Train
- UpdateStatistics() : BaseGraphWindow
- UpdateViewport() : SpecializedVehicle< T, Type >
- UpdateViewportCoordinates() : NWidgetViewport
- UpdateVirtCoord() : BaseStation , Sign , Station , Town , Waypoint
- UpdateVisualEffect() : Vehicle
- UpdateWidgetSize() : GameDifficultyWindow , VehicleDetailsWindow , AIConfigWindow , BuildTreesWindow , RefitWindow , TooltipsWindow , AboutWindow , LandInfoWindow , BuildAirportWindow , IndustryCargoesWindow , ReplaceVehicleWindow , VehicleViewWindow , BuildBridgeWindow , VehicleGroupWindow , PerformanceRatingDetailWindow , CompanyLeagueWindow , BuildVehicleWindow , BaseGraphWindow , CheatWindow , CompanyFinancesWindow , SelectCompanyLiveryWindow , CreateScenarioWindow , TownAuthorityWindow , VehicleListWindow , SelectCompanyManagerFaceWindow , CompanyInfrastructureWindow , CompanyWindow , BuyCompanyWindow , SetDateWindow , DepotWindow , EnginePreviewWindow , StatusBarWindow , GenerateProgressWindow , GoalListWindow , GoalQuestionWindow , SubsidyListWindow , PaymentRatesGraphWindow , AISettingsWindow , ScenarioEditorToolbarWindow , Window , TimetableWindow , NewsWindow , CustomCurrencyWindow , GameOptionsWindow , BuildIndustryWindow , OrdersWindow , MessageHistoryWindow , ScanProgressWindow , NewGRFParametersWindow , TownViewWindow , NetworkClientListWindow , NetworkLobbyWindow , IndustryViewWindow , IndustryDirectoryWindow , CompanyStationsWindow , SelectGameWindow , StationViewWindow , BuildRailWaypointWindow , QueryWindow , MusicTrackSelectionWindow , MusicWindow , NetworkClientListPopupWindow , MessageOptionsWindow , SpriteAlignerWindow , BuildObjectWindow , NetworkJoinStatusWindow , TownDirectoryWindow , BuildRailStationWindow , GameSettingsWindow , NewGRFInspectWindow , SelectStationWindow< T > , AIListWindow
- UpdateZPosition() : GroundVehicle< T, Type >
- UpdateZPositionAndInclination() : GroundVehicle< T, Type >
- upgrade : ContentInfo
- url : GRFConfig , ScriptInfo , ContentInfo , NetworkHTTPContentConnecter
- usage : LinkStat
- Usage() : LinkStat
- usage : LinkProperties
- use_as_random : AIInfo
- use_password : NetworkCompanyInfo , NetworkGameInfo
- UseAsRandomAI() : AIInfo
- used_liveries : GRFLoadedFeatures
- used_set : BaseMedia< Tbase_set >
- UsePaletteAnimation() : Blitter_32bppAnim , Blitter_Null , Blitter_8bppBase , Blitter , Blitter_32bppBase
- user : OrderBackup
- user_def_data : TrainCache , RailVehicleInfo
- UserIsAllowedToChangeNewGRFs() : GUISettings
- UsesSmoothEconomy() : IndustrySpec
- UseTextRefStack() : CommandCost