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
- units : LocaleSettings
- units_volume : CargoSpec
- unshaded_size : Window
- UnshareOrders() : AIOrder
- UpdateListPosition() : NewGRFAddWindow
- UpdateOrderTimetable() : OrderList
- UpdatePosition() : ViewportSign , Scrollbar
- UpdateViewportCoordinates() : NWidgetViewport
- UpdateVirtCoord() : BaseStation , Station
- UpdateWidgetSize() : VehicleDetailsWindow , CompanyStationsWindow , OrdersWindow , AISettingsWindow , NewGRFWindow , NewGRFAddWindow , QueryWindow , QueryStringWindow , TooltipsWindow , ErrmsgWindow , IndustryDirectoryWindow , BuildIndustryWindow , NewsWindow , CompanyWindow , SelectCompanyManagerFaceWindow , SelectCompanyLiveryWindow , BuildTreesWindow , ReplaceVehicleWindow , AIConfigWindow , AIDebugWindow , StationViewWindow , AIListWindow , Window , VehicleViewWindow , SetDateWindow , VehicleListWindow , RefitWindow , CompanyFinancesWindow , SelectStationWindow< T > , TownAuthorityWindow , TownDirectoryWindow
- use_left_mouse_button : TooltipsWindow
- used : AILog::LogData
- used_set : BaseMedia< Tbase_set >
- UsePaletteAnimation() : Blitter