BackRight

BackRight

#Overview

name: BackRight

The value of this variable can be defined or overridden in .ini config files. 2 .ini config files referencing this setting variable.

It is referenced in 48 C++ source files.

#Summary

#Usage in the C++ source code

The purpose of BackRight is to represent the back right audio channel in a multi-channel audio system. This variable is part of the audio rendering and mixing system in Unreal Engine 5, specifically for surround sound configurations.

BackRight is primarily used in the Audio Mixer subsystem of Unreal Engine 5. It’s also referenced in various audio-related plugins and modules, such as:

  1. Avalanche plugin (experimental)
  2. Water plugin
  3. AudioSynesthesia plugin
  4. Synthesis plugin
  5. SignalProcessing module
  6. SoundFieldRendering module
  7. AudioMixerXAudio2 module (Windows-specific)

The value of this variable is typically set when initializing or configuring audio output devices, or when creating channel maps for audio processing and mixing.

BackRight often interacts with other channel variables like FrontLeft, FrontRight, BackLeft, Center, and LowFrequency, as they are all part of various surround sound configurations (e.g., 5.1, 7.1).

Developers should be aware that:

  1. The exact behavior and importance of BackRight may vary depending on the audio configuration and the target platform.
  2. In some cases, the ordering of BackRight in channel arrays might differ between platforms (e.g., Windows vs. other platforms).
  3. The BackRight channel is often used in conjunction with other rear channels to create a more immersive audio experience.

Best practices when using this variable include:

  1. Ensure proper channel mapping when working with different audio configurations.
  2. Consider the target platform and audio hardware capabilities when utilizing surround sound channels.
  3. Test audio output on various speaker configurations to ensure correct channel assignment and balance.
  4. Be aware of potential differences in channel ordering between different audio APIs or platforms.

#Setting Variables

#References In INI files

Location: <Workspace>/Engine/Config/BaseEngine.ini:1576, section: [AudioChannelAzimuthMap]

Location: <Workspace>/Engine/Config/BaseEngine.ini:1592, section: [AudioDefaultChannelOrder]

#References in C++ code

#Callsites

This variable is referenced in the following C++ source code:

#Loc: <Workspace>/Engine/Plugins/Experimental/Avalanche/Source/AvalancheShapes/Private/DynamicMeshes/AvaShapeCubeDynMesh.cpp:397

Scope (from outer to inner):

file
function     bool UAvaShapeCubeDynamicMesh::GenerateBackMeshSections

Source code excerpt:

	const FAvaShapeCachedVertex3D BackLeft = CacheVertexCreate(BackMesh, BackLeftLoc * Scale, BackNormal);
	const FVector BackRightLoc(SegmentSize.X, (SegmentSize.Y - BevelSize.Y), -(SegmentSize.Z - BevelSize.Z));
	const FAvaShapeCachedVertex3D BackRight = CacheVertexCreate(BackMesh, BackRightLoc * Scale, BackNormal);

	AddVertex(BackMesh, BackLeft);
	const FVector BackLeftLoc2(SegmentSize.X, (SegmentSize.Y - BevelSize.Y), (SegmentSize.Z - BevelSize.Z));
	int32 BackLeftIdx = AddVertexRaw(BackMesh, BackLeftLoc2 * Scale, BackNormal);
	AddVertex(BackMesh, BackRight);

	AddVertex(BackMesh, BackRight);
	const FVector BackRightLoc2(SegmentSize.X, -(SegmentSize.Y - BevelSize.Y), -(SegmentSize.Z - BevelSize.Z));
	int32 BackRightIdx = AddVertexRaw(BackMesh, BackRightLoc2 * Scale, BackNormal);
	AddVertex(BackMesh, BackLeft);

	if (BevelSizeRatio > 0)
	{

#Loc: <Workspace>/Engine/Plugins/Experimental/Avalanche/Source/AvalancheShapes/Private/DynamicMeshes/AvaShapeCubeDynMesh.cpp:417

Scope (from outer to inner):

file
function     bool UAvaShapeCubeDynamicMesh::GenerateBackMeshSections

Source code excerpt:

			BevelSize, Scale, FVector(SegmentSize.X, -SegmentSize.Y, SegmentSize.Z), FVector(SegmentSize.X, -SegmentSize.Y, -SegmentSize.Z));

		CreateBevelCorner(BackMesh, BackRightLoc2, BackRightLoc, BackNormal, BackRightIdx, BackRight.Index,
			BevelSize, Scale, FVector(SegmentSize.X, -SegmentSize.Y, -SegmentSize.Z), FVector(SegmentSize.X, SegmentSize.Y, -SegmentSize.Z));

		CreateBevelCorner(BackMesh, BackRightLoc, BackLeftLoc2, BackNormal, BackRight.Index, BackLeftIdx,
			BevelSize, Scale, FVector(SegmentSize.X, SegmentSize.Y, -SegmentSize.Z), FVector(SegmentSize.X, SegmentSize.Y, SegmentSize.Z));
	}

	return true;
}

#Loc: <Workspace>/Engine/Plugins/Experimental/Water/Source/Runtime/Private/WaterBodyRiverComponent.cpp:255

Scope (from outer to inner):

file
function     static void AddTerminalVerticesForRiverSpline

Source code excerpt:

	const FVertexInfo Left(FVector3d(Pos - OutwardDistance + TangentialOffset));
	const FVertexInfo Right(FVector3d(Pos + OutwardDistance + TangentialOffset));
	const FVertexInfo BackRight(FVector3d(Pos + OutwardDistance + TangentialOffset + DilationOffset));

	const int32 BaseIndex = OutDilatedMesh.GetVerticesBuffer().Num();

	OutDilatedMesh.AppendVertex(BackLeft);
	OutDilatedMesh.AppendVertex(Left);
	OutDilatedMesh.AppendVertex(Right);
	OutDilatedMesh.AppendVertex(BackRight);


	if (Edge == ERiverBoundaryEdge::End)
	{
		/* Dilated edge segment geometry:
			 0 --- 1 ------- 2 --- 3

#Loc: <Workspace>/Engine/Plugins/Runtime/AudioSynesthesia/Source/AudioSynesthesiaCore/Private/LoudnessAnalyzer.cpp:223

Scope (from outer to inner):

file
namespace    Audio
function     FMultichannelLoudnessAnalyzer::FMultichannelLoudnessAnalyzer

Source code excerpt:

        // If elevation angle is less than 30 degrees and azimuth is between 60 and 120, set channel weight to 1.5f. 
        ChannelWeights[EAudioMixerChannel::BackLeft] = 1.5f;
        ChannelWeights[EAudioMixerChannel::BackRight] = 1.5f;

        MonoBuffer.Reset(InSettings.FFTSize);
        MonoBuffer.AddUninitialized(InSettings.FFTSize);
    }

    float FMultichannelLoudnessAnalyzer::CalculatePerceptualEnergy(TArrayView<const float> InView, const int32 InNumChannels, TArray<float>& OutChannelEnergies)

#Loc: <Workspace>/Engine/Plugins/Runtime/Synthesis/Source/Synthesis/Private/ConvolutionReverb.cpp:60

Scope (from outer to inner):

file
namespace    Audio
namespace    ConvolutionReverbIntrinsics

Source code excerpt:

				EAudioMixerChannel::Type::FrontCenter,
				EAudioMixerChannel::Type::BackLeft,
				EAudioMixerChannel::Type::BackRight,
				EAudioMixerChannel::Type::SideLeft,
				EAudioMixerChannel::Type::SideRight
			},

			// Eight channels (7.1)
			{

#Loc: <Workspace>/Engine/Plugins/Runtime/Synthesis/Source/Synthesis/Private/ConvolutionReverb.cpp:72

Scope (from outer to inner):

file
namespace    Audio
namespace    ConvolutionReverbIntrinsics

Source code excerpt:

				EAudioMixerChannel::Type::LowFrequency,
				EAudioMixerChannel::Type::BackLeft,
				EAudioMixerChannel::Type::BackRight,
				EAudioMixerChannel::Type::SideLeft,
				EAudioMixerChannel::Type::SideRight
			}
		};

		bool GetReverbOutputChannelTypesForNumChannels(int32 InNumChannels, TArray<EAudioMixerChannel::Type>& OutChannelTypes)

#Loc: <Workspace>/Engine/Plugins/Runtime/Synthesis/Source/Synthesis/Private/SubmixChannelFormatConverter.cpp:28

Scope (from outer to inner):

file
namespace    Audio
namespace    SubmixChannelFormatConverterPrivate

Source code excerpt:

		{
			{ EAudioMixerChannel::FrontLeft, { EAudioMixerChannel::BackLeft, EAudioMixerChannel::SideLeft, EAudioMixerChannel::TopBackLeft } },
			{ EAudioMixerChannel::FrontRight, { EAudioMixerChannel::BackRight, EAudioMixerChannel::SideRight, EAudioMixerChannel::TopBackRight } },
			{ EAudioMixerChannel::FrontCenter, { EAudioMixerChannel::BackCenter, EAudioMixerChannel::TopCenter, EAudioMixerChannel::TopBackCenter } },
			{ EAudioMixerChannel::FrontLeftOfCenter, { EAudioMixerChannel::BackLeft, EAudioMixerChannel::SideLeft, EAudioMixerChannel::TopBackLeft } },
			{ EAudioMixerChannel::FrontRightOfCenter, { EAudioMixerChannel::BackRight, EAudioMixerChannel::SideRight, EAudioMixerChannel::TopBackRight } },
			{ EAudioMixerChannel::TopFrontLeft, { EAudioMixerChannel::BackLeft, EAudioMixerChannel::SideLeft, EAudioMixerChannel::TopBackLeft } },
			{ EAudioMixerChannel::TopFrontRight, { EAudioMixerChannel::BackRight, EAudioMixerChannel::SideRight, EAudioMixerChannel::TopBackRight } },
			{ EAudioMixerChannel::TopFrontCenter, { EAudioMixerChannel::BackCenter, EAudioMixerChannel::TopCenter, EAudioMixerChannel::TopBackCenter } }
		};

		// For a _flipped_ rear-channel-bleed, this map pairs all front channels with all
		// associated rear channels that should receive bled audio.
		static const TMap<EAudioMixerChannel::Type, TArray<EAudioMixerChannel::Type>> PairedFlippedRearChannelTypes =

#Loc: <Workspace>/Engine/Plugins/Runtime/Synthesis/Source/Synthesis/Private/SubmixChannelFormatConverter.cpp:112

Scope (from outer to inner):

file
namespace    Audio
function     bool GetSubmixChannelOrderForNumChannels

Source code excerpt:

						EAudioMixerChannel::Type::LowFrequency,
						EAudioMixerChannel::Type::BackLeft,
						EAudioMixerChannel::Type::BackRight,
						EAudioMixerChannel::Type::SideLeft,
						EAudioMixerChannel::Type::SideRight
					}
				);

				return true;

#Loc: <Workspace>/Engine/Plugins/Runtime/Synthesis/Source/Synthesis/Private/SubmixChannelFormatConverter.cpp:385

Scope (from outer to inner):

file
namespace    Audio
function     bool FSimpleUpmixer::GetSimpleUpmixerStaticMixEntries

Source code excerpt:

		const int32 InputSideRightIndex = InInputChannelTypes.Find(EAudioMixerChannel::Type::SideRight);
		const int32 InputBackLeftIndex = InInputChannelTypes.Find(EAudioMixerChannel::Type::BackLeft);
		const int32 InputBackRightIndex = InInputChannelTypes.Find(EAudioMixerChannel::Type::BackRight);

		// Query which output channels exist
		const int32 OutputFrontLeftIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::FrontLeft);
		const int32 OutputFrontRightIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::FrontRight);
		const int32 OutputSideLeftIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::SideLeft);
		const int32 OutputSideRightIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::SideRight);
		const int32 OutputBackLeftIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::BackLeft);
		const int32 OutputBackRightIndex = InOutputChannelTypes.Find(EAudioMixerChannel::Type::BackRight);

		// Check for mono input and stereo output.
		const bool bInputIsMono = (1 == InInputChannelTypes.Num()) && (InInputChannelTypes[0] == EAudioMixerChannel::Type::FrontCenter); 
		const bool bOutputHasFrontLeft = (INDEX_NONE != OutputFrontLeftIndex);
		const bool bOutputHasFrontRight = (INDEX_NONE != OutputFrontRightIndex);

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Private/AudioMixerChannelMaps.cpp:47

Scope (from outer to inner):

file
namespace    Audio

Source code excerpt:

			EAudioMixerChannel::LowFrequency,
			EAudioMixerChannel::BackLeft,
			EAudioMixerChannel::BackRight,
			EAudioMixerChannel::SideLeft,
			EAudioMixerChannel::SideRight
		},

		// ESubmixChannelFormat::Ambisonics
		// Ambisonics output is encoded to max encoded channel (i.e. 7.1).

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Private/AudioMixerChannelMaps.cpp:62

Scope (from outer to inner):

file
namespace    Audio

Source code excerpt:

			EAudioMixerChannel::LowFrequency,
			EAudioMixerChannel::BackLeft,
			EAudioMixerChannel::BackRight,
			EAudioMixerChannel::SideLeft,
			EAudioMixerChannel::SideRight
		}, 
	};

	// Make a channel map cache

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Private/AudioMixerChannelMaps.cpp:236

Scope (from outer to inner):

file
namespace    Audio
function     void FMixerDevice::InitializeChannelAzimuthMap

Source code excerpt:


		DefaultChannelAzimuthPositions[EAudioMixerChannel::BackLeft] = { EAudioMixerChannel::BackLeft, 210 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::BackRight] = { EAudioMixerChannel::BackRight, 150 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::FrontLeftOfCenter] = { EAudioMixerChannel::FrontLeftOfCenter, 15 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::FrontRightOfCenter] = { EAudioMixerChannel::FrontRightOfCenter, 345 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::BackCenter] = { EAudioMixerChannel::BackCenter, 180 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::SideLeft] = { EAudioMixerChannel::SideLeft, 250 };
		DefaultChannelAzimuthPositions[EAudioMixerChannel::SideRight] = { EAudioMixerChannel::SideRight, 110 };

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Private/AudioMixerDevice.cpp:460

Scope (from outer to inner):

file
namespace    Audio
function     TArray<Audio::FChannelPositionInfo>* FMixerDevice::GetDefaultPositionMap

Source code excerpt:

														,SpeakerPositions[EAudioMixerChannel::LowFrequency] //LFE
														,SpeakerPositions[EAudioMixerChannel::BackLeft] // Left Rear
														,SpeakerPositions[EAudioMixerChannel::BackRight] // Right Rear
														,SpeakerPositions[EAudioMixerChannel::SideLeft] // Left Surround
														,SpeakerPositions[EAudioMixerChannel::SideRight] // Right Surround
				};


				return &SevenDotOneMap;

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Private/AudioMixerSource.cpp:2207

Scope (from outer to inner):

file
lambda-function

Source code excerpt:

							TMap<EAudioMixerChannel::Type, float> RightOmniMap;
							RightOmniMap.Add(EAudioMixerChannel::FrontRight, 1.0f);
							RightOmniMap.Add(EAudioMixerChannel::BackRight, 1.0f);

							return RightOmniMap;
						};

						static const TMap<EAudioMixerChannel::Type, float> LeftOmniMap = CreateLeftOmniMap();
						static const TMap<EAudioMixerChannel::Type, float> RightOmniMap = CreateRightOmniMap();

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Public/AudioMixerBlueprintLibrary.h:62

Scope: file

Source code excerpt:

	LowFrequency,
	BackLeft,
	BackRight,
	FrontLeftOfCenter,
	FrontRightOfCenter,
	BackCenter,
	SideLeft,
	SideRight,
	TopCenter,

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixer/Public/AudioMixerBlueprintLibrary.h:89

Scope (from outer to inner):

file
function     inline const TCHAR* ToString

Source code excerpt:

		case EAudioMixerChannelType::LowFrequency:			return TEXT("LowFrequency");
		case EAudioMixerChannelType::BackLeft:				return TEXT("BackLeft");
		case EAudioMixerChannelType::BackRight:				return TEXT("BackRight");
		case EAudioMixerChannelType::FrontLeftOfCenter:		return TEXT("FrontLeftOfCenter");
		case EAudioMixerChannelType::FrontRightOfCenter:	return TEXT("FrontRightOfCenter");
		case EAudioMixerChannelType::BackCenter:			return TEXT("BackCenter");
		case EAudioMixerChannelType::SideLeft:				return TEXT("SideLeft");
		case EAudioMixerChannelType::SideRight:				return TEXT("SideRight");
		case EAudioMixerChannelType::TopCenter:				return TEXT("TopCenter");

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixerCore/Private/AudioMixer.cpp:816

Scope (from outer to inner):

file
namespace    Audio
function     static void InitializeDefaultChannelOrder

Source code excerpt:

		DefaultChannelOrder[5] = EAudioMixerChannel::SideRight;
		DefaultChannelOrder[6] = EAudioMixerChannel::BackLeft;
		DefaultChannelOrder[7] = EAudioMixerChannel::BackRight;

		bool bOverridden = false;
		EAudioMixerChannel::Type ChannelMapOverride[AUDIO_MIXER_MAX_OUTPUT_CHANNELS];
		for (int32 i = 0; i < AUDIO_MIXER_MAX_OUTPUT_CHANNELS; ++i)
		{
			ChannelMapOverride[i] = DefaultChannelOrder[i];

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixerCore/Public/AudioMixer.h:84

Scope (from outer to inner):

file
namespace    EAudioMixerChannel

Source code excerpt:

		LowFrequency,
		BackLeft,
		BackRight,
		FrontLeftOfCenter,
		FrontRightOfCenter,
		BackCenter,
		SideLeft,
		SideRight,
		TopCenter,

#Loc: <Workspace>/Engine/Source/Runtime/AudioMixerCore/Public/AudioMixer.h:113

Scope (from outer to inner):

file
namespace    EAudioMixerChannel
function     inline const TCHAR* ToString

Source code excerpt:

		case LowFrequency:			return TEXT("LowFrequency");
		case BackLeft:				return TEXT("BackLeft");
		case BackRight:				return TEXT("BackRight");
		case FrontLeftOfCenter:		return TEXT("FrontLeftOfCenter");
		case FrontRightOfCenter:	return TEXT("FrontRightOfCenter");
		case BackCenter:			return TEXT("BackCenter");
		case SideLeft:				return TEXT("SideLeft");
		case SideRight:				return TEXT("SideRight");
		case TopCenter:				return TEXT("TopCenter");

#Loc: <Workspace>/Engine/Source/Runtime/Engine/Public/Audio.h:80

Scope: file

Source code excerpt:

	SPEAKER_LeftSurround,	//	*	*	*	*
	SPEAKER_RightSurround,	//	*	*	*	*
	SPEAKER_LeftBack,		//			*	*		If there is no BackRight channel, this is the BackCenter channel
	SPEAKER_RightBack,		//				*
	SPEAKER_Count
};

// Forward declarations.
class UAudioComponent;

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:48

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:


	static const float Matrix_7_1[] = {
		// FrontLeft	FrontRight	BackLeft	LFE			BackRight	SideLeft	SideRight
		0.707f,			0.707f,		0.5f,		0.0f,		0.5f,		0.5f,		0.5f,		// Mono
	};

	static const float Matrix_8_1[] = {
		// FrontLeft	FrontRight	Center		LowFreq		SideLeft	SideRight	BackLeft	BackRight
		0.707f,			0.707f,		1.0f,		0.0f,		0.5f,		0.5f,		0.5f,		0.5f,		// Mono
	};

	static const float* ToMono[8] = {
		Matrix_1_1,
		Matrix_2_1,

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:107

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:


	static const float Matrix_7_2[] = {
		// FrontLeft	FrontRight	BackLeft	LFE			BackRight	SideLeft	SideRight
		1.0f,			0.0f,		0.707f,		0.0f,		0.0f,		0.707f,		0.0f,		// Left
		0.0f,			1.0f,		0.0f,		0.0f,		0.707f,		0.0f,		0.707f,		// Right
	};

	static const float Matrix_8_2[] = {
		// FrontLeft	FrontRight	Center		LowFreq		SideLeft	SideRight	BackLeft	BackRight
		1.0f,			0.0f,		0.707f,		0.0f,		0.707f,		0.0f,		0.707f,		0.0f,		// Left
		0.0f,			1.0f,		0.707f,		0.0f,		0.0f,		0.707f,		0.0f,		0.707f,		// Right
	};

	static const float* ToStereo[8] = {
		Matrix_1_2,

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:141

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,		// SideRight
		0.0f,		// BackLeft
		0.0f,		// BackRight
	};

	static const float Matrix_2_8[] = {
		// FrontLeft	FrontRight
		1.0f,			0.0f,			// FrontLeft
		0.0f,			1.0f,			// FrontRight

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:153

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,			0.0f,			// SideRight
		0.0f,			0.0f,			// BackLeft
		0.0f,			0.0f,			// BackRight
	};

	static const float Matrix_3_8[] = {
		// FrontLeft	FrontRight	Center
		1.0f,			0.0f,		0.0f,	// FrontLeft
		0.0f,			1.0f,		0.0f,	// FrontRight

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:165

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,			0.0f,		0.0f,	// SideRight
		0.0f,			0.0f,		0.0f,	// BackLeft
		0.0f,			0.0f,		0.0f,	// BackRight
	};

	static const float Matrix_4_8[] = {
		// FrontLeft	FrontRight	SideLeft	SideRight
		1.0f,			0.0f,		0.0f,		0.0f,		// FrontLeft
		0.0f,			1.0f,		0.0f,		0.0f,		// FrontRight

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:177

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,			0.0f,		0.0f,		1.0f,		// SideRight
		0.0f,			0.0f,		0.0f,		0.0f,		// BackLeft
		0.0f,			0.0f,		0.0f,		0.0f,		// BackRight
	};

	static const float Matrix_5_8[] = {
		// FrontLeft	FrontRight	Center		SideLeft	SideRight
		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		// FrontRight

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:189

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		// SideRight
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// BackLeft
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// BackRight
	};

	static const float Matrix_6_8[] = {
		// FrontLeft	FrontRight	Center		LowFreq		SideLeft	SideRight
		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight

#Loc: <Workspace>/Engine/Source/Runtime/MediaUtils/Private/MediaAudioResampler.cpp:201

Scope (from outer to inner):

file
namespace    MediaAudioResampler

Source code excerpt:

		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		// SideRight
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// BackLeft
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// BackRight
	};

	static const float Matrix_7_8[] = {
		// FrontLeft	FrontRight	BackLeft	LFE			BackRight	SideLeft	SideRight
		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// Center
		0.0f,			0.0f,		0.0f,		1.0f,		0.0f,		0.0f,		0.0f,		// LowFrequency
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		0.0f,		// SideLeft
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		// SideRight
		0.0f,			0.0f,		1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// BackLeft
		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		0.0f,		0.0f,		// BackRight
	};

	static const float Matrix_8_8[] = {
		// FrontLeft	FrontRight	Center		LowFreq		SideLeft	SideRight	BackLeft	BackRight
		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
		0.0f,			0.0f,		1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// Center
		0.0f,			0.0f,		0.0f,		1.0f,		0.0f,		0.0f,		0.0f,		0.0f,		// LowFrequency
		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		0.0f,		0.0f,		0.0f,		// SideLeft
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		0.0f,		0.0f,		// SideRight
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		0.0f,		// BackLeft
		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		0.0f,		1.0f,		// BackRight
	};

	static const float* ToSurround[8] = {
		Matrix_1_8,
		Matrix_2_8,
		Matrix_3_8,

#Loc: <Workspace>/Engine/Source/Runtime/NonRealtimeAudioRenderer/Private/AudioMixerPlatformNonRealtime.cpp:169

Scope (from outer to inner):

file
namespace    Audio
function     bool FMixerPlatformNonRealtime::GetOutputDeviceInfo

Source code excerpt:

		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::LowFrequency);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::BackLeft);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::BackRight);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::SideLeft);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::SideRight);

		return true;
	}

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:12

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float ToMonoMatrix[ChannelMapMaxNumChannels * 1] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight  
			0.707f,			0.707f,		1.0f,		0.0f,			0.5f,		0.5f,		0.5f,		0.5f,		// FrontLeft
		};

		static constexpr float VorbisToMonoMatrix[ChannelMapVorbisNumChannels * 1] =
		{
			// FrontLeft	Center		FrontRight	SideLeft		SideRight	LowFrequency

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:24

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float ToStereoMatrix[ChannelMapMaxNumChannels * 2] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight  
			1.0f,			0.0f,		0.707f,		0.0f,			0.707f,		0.0f,		0.707f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.707f,		0.0f,			0.0f,		0.707f,		0.0f,		0.707f,		// FrontRight
		};

		static constexpr float VorbisToStereoMatrix[ChannelMapVorbisNumChannels * 2] =
		{

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:38

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float ToTriMatrix[ChannelMapMaxNumChannels * 3] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight  
			1.0f,			0.0f,		0.0f,		0.0f,			0.707f,		0.0f,		0.707f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.0f,		0.0f,			0.0f,		0.707f,		0.0f,		0.707f,		// FrontRight
			0.0f,			0.0f,		1.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// Center
		};

		static constexpr float VorbisToTriMatrix[ChannelMapVorbisNumChannels * 3] =

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:54

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float ToQuadMatrix[ChannelMapMaxNumChannels * 4] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight	
			1.0f,			0.0f,		0.707f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.707f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		1.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		1.0f,		// SideRight
		};

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:72

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float To5Matrix[ChannelMapMaxNumChannels * 5] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight	
			1.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		1.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// Center
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		1.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		1.0f,		// SideRight
		};

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:92

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float To5Point1Matrix[ChannelMapMaxNumChannels * 6] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight	
			1.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		1.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// Center
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// LowFrequency
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		1.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		1.0f,		// SideRight

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:114

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

		static constexpr float ToHexMatrix[ChannelMapMaxNumChannels * 7] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight	
			1.0f,			0.0f,		0.707f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.707f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		1.0f,		0.0f,		// BackLeft
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// LFE
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		// BackRight
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		0.0f,		// SideRight
		};

		static constexpr float VorbisToHexMatrix[ChannelMapVorbisNumChannels * 7] =
		{

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:131

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		// BackLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		// LFE
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		// BackRight
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		// SideRight
		};

#if PLATFORM_MICROSOFT

		static constexpr float To7Point1Matrix[ChannelMapMaxNumChannels * 8] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight
			1.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		1.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontCenter
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// LowFrequency
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		0.0f,		// SideRight
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		1.0f,		0.0f,		// BackLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		// BackRight
		};

#else //PLATFORM_MICROSOFT

		// NOTE: the BackLeft/BackRight and SideLeft/SideRight are reversed than they should be since our 7.1 importer code has it backward
		static constexpr float To7Point1Matrix[ChannelMapMaxNumChannels * 8] =
		{
			// FrontLeft	FrontRight	Center		LowFrequency	SideLeft	SideRight	BackLeft	BackRight
			1.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontLeft
			0.0f,			1.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontRight
			0.0f,			0.0f,		1.0f,		0.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// FrontCenter
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		0.0f,		0.0f,		// LowFrequency
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		1.0f,		0.0f,		// BackLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		0.0f,		1.0f,		// BackRight
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		0.0f,		0.0f,		// SideLeft
			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		1.0f,		0.0f,		0.0f,		// SideRight
		};

#endif//PLATFORM_MICROSOFT

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ChannelMap.cpp:179

Scope (from outer to inner):

file
namespace    Audio
namespace    ChannelMapPrivate

Source code excerpt:

			0.0f,			0.0f,		0.0f,		0.0f,			0.0f,		0.0f,		// SideRight
			0.0f,			0.0f,		0.0f,		1.0f,			0.0f,		0.0f,		// BackLeft
			0.0f,			0.0f,		0.0f,		0.0f,			1.0f,		0.0f,		// BackRight
		};

		static float const * const OutputChannelMaps[ChannelMapMaxNumChannels] =
		{
			ToMonoMatrix,
			ToStereoMatrix,

#Loc: <Workspace>/Engine/Source/Runtime/SignalProcessing/Private/ReverbFast.cpp:236

Scope (from outer to inner):

file
namespace    Audio
function     void FPlateReverbFast::InterleaveAndMixOutput

Source code excerpt:

					OutSampleData[OutPos + EAudioMixerChannel::FrontRight] = FrontRightSampleData[i];
					OutSampleData[OutPos + EAudioMixerChannel::BackLeft] = BackLeftSampleData[i];
					OutSampleData[OutPos + EAudioMixerChannel::BackRight] = BackRightSampleData[i];
				}
			}
		}
	}

	void FPlateReverbFast::ApplySettings()

#Loc: <Workspace>/Engine/Source/Runtime/SoundFieldRendering/Private/SoundFieldRendering.cpp:56

Scope (from outer to inner):

file
function     FSoundFieldDecoder::FSoundFieldDecoder

Source code excerpt:

	constexpr const int32 FrontCenterOffset = NumAmbiChannels * EAudioMixerChannel::FrontCenter;
	constexpr const int32 BackLeftOffest    = NumAmbiChannels * EAudioMixerChannel::BackLeft;
	constexpr const int32 BackRightOffset   = NumAmbiChannels * EAudioMixerChannel::BackRight;
	constexpr const int32 BackCenterOffset  = NumAmbiChannels * EAudioMixerChannel::BackCenter;

	VectorRegister FrontLeftGains   = VectorLoadAligned(SpeakerGainsPtr);
	VectorRegister FrontRightGains  = VectorLoadAligned(SpeakerGainsPtr + FrontRightOffset);
	VectorRegister FrontCenterGains = VectorLoadAligned(SpeakerGainsPtr + FrontCenterOffset);
	VectorRegister BackLeftGains    = VectorLoadAligned(SpeakerGainsPtr + BackLeftOffest);

#Loc: <Workspace>/Engine/Source/Runtime/SoundFieldRendering/Private/SoundFieldRendering.cpp:689

Scope: file

Source code excerpt:

	,{EAudioMixerChannel::LowFrequency, -1, 0}
	,{EAudioMixerChannel::BackLeft, 210, 0} 
	,{EAudioMixerChannel::BackRight, 150, 0}
	,{EAudioMixerChannel::SideLeft, 250, 0}
	,{EAudioMixerChannel::SideRight, 110, 0}
	,{EAudioMixerChannel::BackCenter, 180,0}
};

FSoundFieldEncoder::FSoundFieldEncoder()

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/AudioMixerPlatformXAudio2.cpp:861

Scope (from outer to inner):

file
namespace    Audio
function     static bool GetMMDeviceInfo

Source code excerpt:

					EAudioMixerChannel::SideRight,
					EAudioMixerChannel::BackLeft,
					EAudioMixerChannel::BackRight,
				};

				EAudioMixerChannel::Type* ChannelOrdering = DefaultChannelOrdering;

				// Override channel ordering for some special cases
				if (OutInfo.NumChannels == 4)

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/AudioMixerPlatformXAudio2.cpp:873

Scope (from outer to inner):

file
namespace    Audio
function     static bool GetMMDeviceInfo

Source code excerpt:

						EAudioMixerChannel::FrontRight,
						EAudioMixerChannel::BackLeft,
						EAudioMixerChannel::BackRight,
					};

					ChannelOrdering = DefaultChannelOrderingQuad;
				}
				else if (OutInfo.NumChannels == 6)
				{

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/AudioMixerPlatformXAudio2.cpp:886

Scope (from outer to inner):

file
namespace    Audio
function     static bool GetMMDeviceInfo

Source code excerpt:

						EAudioMixerChannel::LowFrequency,
						EAudioMixerChannel::BackLeft,
						EAudioMixerChannel::BackRight,
					};

					ChannelOrdering = DefaultChannelOrdering51;
				}

				check(OutInfo.NumChannels <= 8);

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/AudioMixerPlatformXAudio2.cpp:1037

Scope (from outer to inner):

file
namespace    Audio
function     bool FMixerPlatformXAudio2::GetOutputDeviceInfo

Source code excerpt:

		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::LowFrequency);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::BackLeft);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::BackRight);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::SideLeft);
		OutInfo.OutputChannelArray.Add(EAudioMixerChannel::SideRight);
		return true;
#endif 
	}

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/WindowsMMDeviceInfoCache.cpp:137

Scope (from outer to inner):

file
namespace    Audio
function     bool FWindowsMMDeviceCache::EnumerateChannelMask

Source code excerpt:

			EAudioMixerChannel::SideRight,
			EAudioMixerChannel::BackLeft,
			EAudioMixerChannel::BackRight,
		};

		const EAudioMixerChannel::Type* ChannelOrdering = DefaultChannelOrdering;

		// Override channel ordering for some special cases
		if (OutInfo.NumChannels == 4)

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/WindowsMMDeviceInfoCache.cpp:149

Scope (from outer to inner):

file
namespace    Audio
function     bool FWindowsMMDeviceCache::EnumerateChannelMask

Source code excerpt:

				EAudioMixerChannel::FrontRight,
				EAudioMixerChannel::BackLeft,
				EAudioMixerChannel::BackRight,
			};

			ChannelOrdering = DefaultChannelOrderingQuad;
		}
		else if (OutInfo.NumChannels == 6)
		{

#Loc: <Workspace>/Engine/Source/Runtime/Windows/AudioMixerXAudio2/Private/WindowsMMDeviceInfoCache.cpp:162

Scope (from outer to inner):

file
namespace    Audio
function     bool FWindowsMMDeviceCache::EnumerateChannelMask

Source code excerpt:

				EAudioMixerChannel::LowFrequency,
				EAudioMixerChannel::BackLeft,
				EAudioMixerChannel::BackRight,
			};

			ChannelOrdering = DefaultChannelOrdering51;
		}

		check(OutInfo.NumChannels <= 8);