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

### - u -

- UnfocusFocusedWidget() : Window
- uninit_read : SaveLoadFormat
- uninit_write : SaveLoadFormat
- Uninitialize() : AI
- unique_id : ContentInfo
- unitnumber_digits : BaseVehicleListWindow
- units : LocaleSettings
- units_volume : CargoSpec
- UnreserveSingleTrack() : CYapfReserveTrack< Types >
- Unselect() : ClientNetworkContentSocketHandler
- UnselectAll() : ClientNetworkContentSocketHandler
- UNSELECTED : ContentInfo
- UnselectVehicle() : VehicleGroupWindow
- unshaded_size : Window
- UnshareOrders() : AIOrder
- unwanted : Town
- UpdateDeltaXY() : Aircraft , EffectVehicle , RoadVehicle , Ship , Train , Vehicle , DisasterVehicle
- UpdateListPosition() : NewGRFAddWindow
- UpdateOptionWidgetStatus() : BuildRoadToolbarWindow
- UpdateOrderTimetable() : OrderList
- UpdateOskState() : OskWindow
- UpdatePosition() : ViewportSign , Scrollbar
- UpdateSelectionStates() : TimetableWindow
- UpdateSpeed() : Train
- UpdateStatistics() : BaseGraphWindow
- UpdateViewport() : Vehicle
- UpdateViewportCoordinates() : NWidgetViewport
- UpdateVirtCoord() : BaseStation , Sign , Station , Town , Waypoint
- UpdateVisualEffect() : Train
- UpdateWidgetSize() : MessageHistoryWindow , MessageOptionsWindow , NewGRFWindow , NewGRFAddWindow , NetworkJoinStatusWindow , BuildRailStationWindow , NetworkClientListPopupWindow , NetworkLobbyWindow , NetworkStartServerWindow , VehicleGroupWindow , NetworkContentListWindow , NetworkChatWindow , MusicWindow , BuildIndustryWindow , SaveLoadWindow , QueryWindow , IndustryViewWindow , IndustryDirectoryWindow , ErrmsgWindow , CompanyStationsWindow , SelectGameWindow , LandInfoWindow , TownDirectoryWindow , AboutWindow , GameOptionsWindow , TooltipsWindow , PerformanceRatingDetailWindow , CompanyLeagueWindow , PaymentRatesGraphWindow , QueryStringWindow , GenerateProgressWindow , Window , GenerateLandscapeWindow , GameDifficultyWindow , DepotWindow , SetDateWindow , BuyCompanyWindow , ScenarioEditorToolbarWindow , SelectCompanyManagerFaceWindow , SelectStationWindow< T > , CompanyFinancesWindow , MusicTrackSelectionWindow , BuildVehicleWindow , BuildBridgeWindow , ReplaceVehicleWindow , NewsWindow , AIConfigWindow , NetworkClientListWindow , AIListWindow , NetworkGameWindow , GameSettingsWindow , OrdersWindow , BuildTreesWindow , VehicleDetailsWindow , AISettingsWindow , RefitWindow , AIDebugWindow , VehicleListWindow , SubsidyListWindow , BaseGraphWindow , CreateScenarioWindow , VehicleViewWindow , TownViewWindow , CompanyWindow , SelectCompanyLiveryWindow , SignListWindow , StationViewWindow , CheatWindow , CustomCurrencyWindow , TownAuthorityWindow , TimetableWindow , EnginePreviewWindow , StatusBarWindow
- upgrade : ContentInfo
- url : ContentInfo , NetworkHTTPContentConnecter
- use_left_mouse_button : TooltipsWindow
- use_password : NetworkCompanyInfo , NetworkGameInfo
- UseAsRandomAI() : AIInfo
- used : AILog::LogData
- used_set : BaseMedia< Tbase_set >
- UsePaletteAnimation() : Blitter_32bppBase , Blitter_8bppBase , Blitter_Null , Blitter , Blitter_32bppAnim
- user_def_data : RailVehicleInfo