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> Unreal Engine API Reference > Runtime > Core > Misc > FApp

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FApp

Provides information about the application.

Windows

MacOS

Linux

References

Module	Core
Header	/Engine/Source/Runtime/Core/Public/Misc/App.h
Include	#include "Misc/App.h"

Syntax

class FApp

Remarks

Provides information about the application.

Functions

	Name	Description
void	AuthorizeUser ( const FString& UserName )	Add the specified user to the list of authorized session users.
bool	CanEverRender()	Checks whether this application can render anything.
bool	CanEverRenderAudio()	Checks whether this application can render audio.
void	DenyAllUsers()	Removes all authorized users.
void	DenyUser ( const FString& UserName )	Remove the specified user from the list of authorized session users.
FString	GetBranchName()	Gets the name of the version control branch that this application was built from.
EBuildConfig...	GetBuildConfiguration()	Gets the application's build configuration, i.e. Debug or Shipping.
FString	GetBuildDate()	Gets the date at which this application was built.
EBuildTarget...	GetBuildTargetType()	Gets the target type of the current application (eg. client, server, etc...)
const TCHAR ...	GetBuildVersion()	Gets the unique version string for this build.
TOptional< F...	GetCurrentFrameTime()	Gets a frame number generated by the engine's timecode provider.
double	GetCurrentTime()	Gets current time in seconds.
double	GetDeltaTime()	Gets time delta in seconds.
int32	GetEngineIsPromotedBuild()	Gets the value of ENGINE_IS_PROMOTED_BUILD.
FString	GetEpicProductIdentifier()	Gets the identifier for the unreal engine
double	GetFixedDeltaTime()	Gets time step in seconds if a fixed delta time is wanted.
double	GetGameTime()	Gets overall game time in seconds.
FString	GetGraphicsRHI()	Gets the name of the graphics RHI currently in use.
double	GetIdleTime()	Gets idle time in seconds.
double	GetIdleTimeOvershoot()	Gets idle time overshoot in seconds (the time beyond the wait time we requested for the frame).
FGuid	GetInstanceId()	Gets the globally unique identifier of this application instance.
FString	GetInstanceName()	Gets the name of this application instance.
double	GetLastTime()	Gets previous value of CurrentTime.
FString	GetName()	Gets the name of the application, i.e. "UE4" or "Rocket".
const TCHAR ...	GetProjectName()	Gets the name of the current project.
FGuid	GetSessionId()	Gets the identifier of the session that this application is part of.
FString	GetSessionName()	Gets the name of the session that this application is part of, if any.
FString	GetSessionOwner()	Gets the name of the user who owns the session that this application is part of, if any.
FTimecode	GetTimecode()	Convert the current frame time into a readable timecode.
FFrameRate	GetTimecodeFrameRate()	Get the frame rate of the current frame time.
float	GetUnfocusedVolumeMultiplier()	Helper function to get UnfocusedVolumeMultiplier from config and store so it's not retrieved every frame
float	GetVolumeMultiplier()	Get Volume Multiplier
bool	HasProjectName()	Reports if the project name has been set
bool	HasVRFocus()	Gets VRFocus, which indicates that the application should continue to render Audio and Video as if it had window focus, even though it may not.
void	InitializeSession()	Initializes the application session.
void	InvalidateCurrentFrameTime()	Invalidate the current frame time. It will reset the TOptional.
bool	IsAuthorizedUser ( const FString& UserName )	Check whether the specified user is authorized to interact with this session.
bool	IsBenchmarking()	Checks whether application is in benchmark mode.
bool	IsEngineInstalled()	Checks whether the engine components of this application have been installed.
bool	IsGame()	Checks whether this application is a game.
bool	IsInstalled()	Checks whether this application has been installed.
bool	IsProjectNameEmpty()	Reports if the project name is empty
bool	IsStandalone()	Checks whether this is a standalone application.
bool	IsThisInstance ( const FGuid& InInstanceId )	Check whether the given instance ID identifies this instance.
bool	IsUnattended()	Checks whether this application runs unattended.
void	PrintStartupLogMessages()	Print all initial startup logging
void	SetBenchmarking ( bool bVal )	Sets application benchmarking mode.
void	SetCurrentFrameTime ( FQualifiedFrameTime InFrameTime )	Sets the current frame time.
void	SetCurrentTime ( double Seconds )	Sets current time in seconds.
void	SetDeltaTime ( double Seconds )	Sets time delta in seconds.
void	SetFixedDeltaTime ( double Seconds )	Sets time step in seconds if a fixed delta time is wanted.
void	SetGameTime ( double Seconds )	Sets overall game time in seconds.
void	SetGraphicsRHI ( FString RHIString )	Sets the Graphics RHI currently in use
void	SetHasVRFocus ( bool bInHasVRFocus )	Sets VRFocus, which indicates that the application should continue to render Audio and Video as if it had window focus, even though it may not.
void	SetIdleTime ( double Seconds )	Sets idle time in seconds.
void	SetIdleTimeOvershoot ( double Seconds )	Sets idle time overshoot in seconds (the time beyond the wait time we requested for the frame).
void	SetProjectName ( const TCHAR* InProjectName )	Sets the name of the current project.
void	SetSessionName ( const FString& NewName )	Set a new session name.
void	SetSessionOwner ( const FString& NewOwner )	Set a new session owner.
void	SetUnfocusedVolumeMultiplier ( float InVolumeMultiplier )	Sets the Unfocused Volume Multiplier
void	SetUseFixedTimeStep ( bool bVal )	Enables or disabled usage of fixed time step.
void	SetUseVRFocus ( bool bInUseVRFocus )	Sets if VRFocus should be used.
void	SetVolumeMultiplier ( float InVolumeMultiplier )	Set Volume Multiplier
bool	ShouldUseThreadingForPerformance()	Checks whether the application should run multi-threaded for performance critical features.
void	UpdateLastTime()	Updates Last time to CurrentTime.
bool	UseFixedTimeStep()	Gets whether we want to use a fixed time step or not.
bool	UseVRFocus()	Gets if VRFocus should be used

Constants

Name	Description
bHasVRFocus	Holds a flag indicating if app has focus in side the VR headset
bIsBenchmarking	Holds a flag Whether we are in benchmark mode or not.
bUseDropFrameFormatWhenSupported	Holds if we should generate a drop frame timecode when the frame rate does support it.
bUseFixedSeed	If the random seed started with a constant or on time, can be affected by -FIXEDSEED or -BENCHMARK
bUseFixedTimeStep	Holds a flag whether we want to use a fixed time step or not.
bUseVRFocus	Holds a flag indicating if VRFocus should be used
CurrentFrameTime	Holds the current frame time and framerate.
CurrentTime	Holds current time.
DeltaTime	Holds current delta time in seconds.
FixedDeltaTime	Holds time step if a fixed delta time is wanted.
GameTime	Holds overall game time.
GraphicsRHI	Holds the name the graphics RHI currently in use
IdleTime	Holds time we spent sleeping in UpdateTimeAndHandleMaxTickRate() if our frame time was smaller than one allowed by target FPS.
IdleTimeOvershoot	Holds the amount of IdleTime that was LONGER than we tried to sleep.
InstanceId	Holds the instance identifier.
LastTime	Holds previous value of CurrentTime.
SessionId	Holds the session identifier.
SessionName	Holds the session name.
SessionOwner	Holds the name of the user that launched session.
SessionUsers	List of authorized session users.
Standalone	Holds a flag indicating whether this is a standalone session.
UnfocusedVolumeMultiplier	Read from config to define the volume when app loses focus
VolumeMultiplier	Use to affect the app volume when it loses focus

Deprecated Functions

		Name	Description
	void	SetTimecodeAndFrameRate ( FTimecode InTimecode, FFrameRate InTimecodeFrameRate )	Please use SetQualifiedFrameTime

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