IAudioMixerPlatformInterface

Abstract interface for mixer platform.

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Inheritance Hierarchy

IAudioMixerDeviceChangedListener

IAudioMixerPlatformInterface

FMixerPlatformNonRealtime

References

Module	AudioMixerCore
Header	/Engine/Source/Runtime/AudioMixerCore/Public/AudioMixer.h
Include	#include "AudioMixer.h"

Syntax

class IAudioMixerPlatformInterface :
    public FRunnable,
    public FSingleThreadRunnable,
    public Audio::IAudioMixerDeviceChangedListener

Remarks

Abstract interface for mixer platform.

Variables

	Name	Description
FEvent *	AudioFadeEvent	Event allows you to block until fadeout is complete.
FEvent *	AudioRenderEvent	The render thread sync event.
TUniquePtr< FRu...	AudioRenderThread	FRunnableThread* AudioRenderThread;.
FAudioOutputStr...	AudioStreamInfo	The audio device stream info.
FThreadSafeBool	bFadedOut
FThreadSafeBool	bIsDeviceInitialized
FThreadSafeBool	bIsGeneratingAudio
FThreadSafeBool	bIsInDeviceSwap	This is used if we are attempting to TryLock on DeviceSwapCriticalSection, but a buffer callback is being called in the current thread.
FThreadSafeBool	bIsUsingNullDevice
FThreadSafeBool	bMoveAudioStreamToNewAudioDevice
FThreadSafeBool	bPerformingFade
bool	bWarnedBufferUnderrun	Whether or not we warned of buffer underrun.
int32	CallCounterApplyAttenuationInternal
int32	CallCounterReadNextBuffer
FString	CurrentDeviceName	This device name can be used to override the default device being used on platforms that use strings to identify audio devices.
FCriticalSectio...	DeviceSwapCriticalSection	Critical Section used for times when we need the render loop to halt for the device swap.
FParam	FadeParam	Source param used to fade in and out audio device.
float	FadeVolume	The fade value. Used for fading in/out master audio.
const int32	InstanceID	A Unique ID Identifying this instance. Mostly used for logging.
FString	LastError	String containing the last generated error.
int32	NumOutputBuffers	The number of mixer buffers to queue on the output source voice.
FAudioMixerOpen...	OpenStreamParams
Audio::FOutputB...	OutputBuffer	List of generated output buffers.

Constructors

	Name	Description
	IAudioMixerPlatformInterface()	Constructor.

Destructors

	Name	Description
	~IAudioMixerPlatformInterface()	Virtual destructor.

Functions

	Name	Description
void	ApplyAttenuationInternal ( TArrayView< BufferType >& InOutBuf... )
void	ApplyMasterAttenuation ( TArrayView< const uint8 >& InOutPo... )	Performs buffer fades for shutdown/startup of audio mixer.
void	AudioMixerPlatformLogOnce ( const FString& LogDetails, const FString& FileName, int32 LineNumber, ELogVerbosity::Type InVerbosity )	Is called when an error, warning or log is generated.
void	BeginGeneratingAudio()	Start generating audio from our mixer.
bool	CheckAudioDeviceChange()	Check if audio device changed if applicable. Return true if audio device changed.
bool	CloseAudioStream()	Closes the audio stream (if it's open).
ICompressedA...	CreateCompressedAudioInfo ( USoundWave* SoundWave )	Creates a Compressed audio info class suitable for decompressing this SoundWave.
ICompressedA...	CreateCompressedAudioInfo ( const FSoundWaveProxyPtr& SoundWav... )
void	CreateNullDeviceThread ( const TFunction< void()> InCallback, float InBufferDuration, bool bShouldPauseOnStart )	Called by platform specific logic to pre-create or create the null renderer thread
bool	DisablePCMAudioCaching()	Whether or not the platform disables caching of decompressed PCM data (i.e. to save memory on fixed memory platforms)
void	FadeIn()	Reset the fade state (use if reusing audio platform interface, e.g. in main audio device.
void	FadeOut()	Start a fadeout. Prevents pops during shutdown.
bool	GetChannelTypeAtIndex ( const int32 Index, EAudioMixerChannel::Type& OutType )	Helper function to gets the channel map type at the given index.
FString	GetCurrentDeviceName()	Returns the name of the currently used audio device.
FString	GetDefaultDeviceName()	Return any optional device name defined in platform configuratio.
bool	GetDefaultOutputDeviceIndex ( uint32& OutDefaultDeviceIndex )	Returns the default device index.
IAudioPlatfo...	GetDeviceInfoCache()	Get the DeviceInfo Cache if one exists.
int32	GetIndexForDevice ( const FString& InDeviceName )	Can be used to look up the current index for a given device name.
FString	GetLastError()	Returns the last error generated.
int32	GetNumFrames ( const int32 InNumReqestedFrames )	Allows platforms to filter the requested number of frames to render.
bool	GetNumOutputDevices ( uint32& OutNumOutputDevices )	Returns the number of output devices.
bool	GetOutputDeviceInfo ( const uint32 InDeviceIndex, FAudioPlatformDeviceInfo& OutInfo )	Gets the device information of the given device index.
EAudioMixerP...	GetPlatformApi()	Returns the platform API enumeration.
FAudioPlatfo...	GetPlatformDeviceInfo()	Returns the platform device info of the currently open audio stream.
FAudioPlatfo...	GetPlatformSettings()	Gets the platform specific audio settings.
FName	GetRuntimeFormat ( USoundWave* InSoundWave )	Returns the name of the format of the input sound wave.
bool	HasCompressedAudioInfoClass ( USoundWave* InSoundWave )	Checks if the platform has a compressed audio format for sound waves.
bool	InitializeHardware()	Initialize the hardware.
bool	IsInitialized()	Is the hardware initialized.
bool	IsNonRealtime()	Whether this is an interface for a non-realtime renderer.
uint32	MainAudioDeviceRun()	Run the "main" audio device.
bool	MoveAudioStreamToNewAudioDevice ( const FString& InNewDeviceId )	Resets the audio stream to use a new audio device with the given device ID (empty string means default).
void	OnHardwareUpdate()	Function called at the beginning of every call of UpdateHardware on the audio thread.
bool	OpenAudioStream ( const FAudioMixerOpenStreamParams&... )	Opens up a new audio stream with the given parameters.
void	PostInitializeHardware()	This is called after InitializeHardware() is called.
void	ReadNextBuffer()	Retrieves the next generated buffer and feeds it to the platform mixer output stream.
bool	RequestDeviceSwap ( const FString& DeviceID, bool bInForce, const TCHAR* InReason )	Sends a command to swap which output device is being used
void	ResumeContext()	Function to resume audio rendering. Used on mobile platforms which can suspend the application.
void	ResumePlaybackOnNewDevice()	Resumes playback on new audio device after device change.
uint32	RunInternal()	Wrapper around the thread Run. This is virtualized so a platform can fundamentally override the render function.
bool	StartAudioStream()	Starts the audio stream processing and generating audio.
void	StartRunningNullDevice()	When called, spins up a thread to start consuming output when no audio device is available.
bool	StopAudioStream()	Stops the audio stream (but keeps the audio stream open).
void	StopGeneratingAudio()	Stops the render thread from generating audio.
void	StopRunningNullDevice()	When called, terminates the null device.
void	SubmitBuffer ( const uint8* Buffer )	Submit the given buffer to the platform's output audio device.
bool	SupportsHardwareDecompression()	Whether or not this platform has hardware decompression.
bool	SupportsRealtimeDecompression()	Whether or not the platform supports realtime decompression.
void	SuspendContext()	Function to stop all audio from rendering. Used on mobile platforms which can suspend the application.
bool	TeardownHardware()	Teardown the hardware.

Overridden from FRunnable

		Name	Description
	FSingleThrea...	GetSingleThreadInterface()	FSingleThreadRunnable accessor for ticking this FRunnable when multi-threading is disabled.
	uint32	Run()	Runs the runnable object.

Overridden from FSingleThreadRunnable

		Name	Description
	void	Tick()	Tick function.

Constants

Name	Description
NextInstanceID	A Counter to provide the next unique id.