Add macOS native Audio Backend

Adds Ryujinx.Audio.Backends.Apple, which is a AudioToolbox based audio backend for macOS (and by extension iOS). Also added in MeloNX.

* Expose AudioToolkit in UI

Co-authored-by: GreemDev <greemdev@ryujinx.app>

Ryujinx.slnx

@@ -6,6 +6,7 @@
     <File Path="nuget.config" />
   </Folder>
   <Project Path="src/ARMeilleure/ARMeilleure.csproj" />
+  <Project Path="src/Ryujinx.Audio.Backends.Apple/Ryujinx.Audio.Backends.Apple.csproj" />
   <Project Path="src/Ryujinx.Audio.Backends.OpenAL/Ryujinx.Audio.Backends.OpenAL.csproj" />
   <Project Path="src/Ryujinx.Audio.Backends.SDL2/Ryujinx.Audio.Backends.SDL2.csproj" />
   <Project Path="src/Ryujinx.Audio.Backends.SoundIo/Ryujinx.Audio.Backends.SoundIo.csproj" />

src/Ryujinx.Audio.Backends.Apple/AppleAudioBuffer.cs

@@ -0,0 +1,16 @@
+namespace Ryujinx.Audio.Backends.Apple
+{
+    class AppleAudioBuffer
+    {
+        public readonly ulong DriverIdentifier;
+        public readonly ulong SampleCount;
+        public ulong SamplePlayed;
+
+        public AppleAudioBuffer(ulong driverIdentifier, ulong sampleCount)
+        {
+            DriverIdentifier = driverIdentifier;
+            SampleCount = sampleCount;
+            SamplePlayed = 0;
+        }
+    }
+}

src/Ryujinx.Audio.Backends.Apple/AppleHardwareDeviceDriver.cs

@@ -0,0 +1,211 @@
+using Ryujinx.Audio.Common;
+using Ryujinx.Audio.Integration;
+using Ryujinx.Memory;
+using System;
+using System.Collections.Concurrent;
+using System.Runtime.InteropServices;
+using System.Runtime.Versioning;
+using System.Threading;
+using static Ryujinx.Audio.Backends.Apple.Native.AudioToolbox;
+using static Ryujinx.Audio.Integration.IHardwareDeviceDriver;
+
+namespace Ryujinx.Audio.Backends.Apple
+{
+    [SupportedOSPlatform("macos")]
+    [SupportedOSPlatform("ios")]
+    public class AppleHardwareDeviceDriver : IHardwareDeviceDriver
+    {
+        private readonly ManualResetEvent _updateRequiredEvent;
+        private readonly ManualResetEvent _pauseEvent;
+        private readonly ConcurrentDictionary<AppleHardwareDeviceSession, byte> _sessions;
+        private readonly bool _supportSurroundConfiguration;
+
+        public float Volume { get; set; }
+
+        public AppleHardwareDeviceDriver()
+        {
+            _updateRequiredEvent = new ManualResetEvent(false);
+            _pauseEvent = new ManualResetEvent(true);
+            _sessions = new ConcurrentDictionary<AppleHardwareDeviceSession, byte>();
+
+            _supportSurroundConfiguration = TestSurroundSupport();
+
+            Volume = 1f;
+        }
+
+        private bool TestSurroundSupport()
+        {
+            try
+            {   
+                var format = GetAudioFormat(SampleFormat.PcmFloat, Constants.TargetSampleRate, 6);
+                
+                int result = AudioQueueNewOutput(
+                    ref format,
+                    IntPtr.Zero,
+                    IntPtr.Zero,
+                    IntPtr.Zero,
+                    IntPtr.Zero,
+                    0,
+                    out IntPtr testQueue);
+
+                if (result == 0)
+                {
+                    AudioChannelLayout layout = new AudioChannelLayout
+                    {
+                        AudioChannelLayoutTag = kAudioChannelLayoutTag_MPEG_5_1_A,
+                        AudioChannelBitmap = 0,
+                        NumberChannelDescriptions = 0
+                    };
+
+                    int layoutResult = AudioQueueSetProperty(
+                        testQueue, 
+                        kAudioQueueProperty_ChannelLayout, 
+                        ref layout, 
+                        (uint)Marshal.SizeOf<AudioChannelLayout>());
+
+                    if (layoutResult == 0)
+                    {
+                        AudioQueueDispose(testQueue, true);
+                        return true;
+                    }
+                    
+                    AudioQueueDispose(testQueue, true);
+                }
+
+                return false;
+            }
+            catch
+            {
+                return false;
+            }
+        }
+
+        public static bool IsSupported => OperatingSystem.IsMacOSVersionAtLeast(10, 5);
+
+        public ManualResetEvent GetUpdateRequiredEvent()
+        {
+            return _updateRequiredEvent;
+        }
+
+        public ManualResetEvent GetPauseEvent()
+        {
+            return _pauseEvent;
+        }
+
+        public IHardwareDeviceSession OpenDeviceSession(Direction direction, IVirtualMemoryManager memoryManager, SampleFormat sampleFormat, uint sampleRate, uint channelCount)
+        {
+            if (channelCount == 0)
+            {
+                channelCount = 2;
+            }
+
+            if (sampleRate == 0)
+            {
+                sampleRate = Constants.TargetSampleRate;
+            }
+
+            if (direction != Direction.Output)
+            {
+                throw new NotImplementedException("Input direction is currently not implemented on Apple backend!");
+            }
+
+            AppleHardwareDeviceSession session = new(this, memoryManager, sampleFormat, sampleRate, channelCount);
+
+            _sessions.TryAdd(session, 0);
+
+            return session;
+        }
+
+        internal bool Unregister(AppleHardwareDeviceSession session)
+        {
+            return _sessions.TryRemove(session, out _);
+        }
+
+        internal static AudioStreamBasicDescription GetAudioFormat(SampleFormat sampleFormat, uint sampleRate, uint channelCount)
+        {
+            uint formatFlags;
+            uint bitsPerChannel;
+
+            switch (sampleFormat)
+            {
+                case SampleFormat.PcmInt8:
+                    formatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
+                    bitsPerChannel = 8;
+                    break;
+                case SampleFormat.PcmInt16:
+                    formatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
+                    bitsPerChannel = 16;
+                    break;
+                case SampleFormat.PcmInt32:
+                    formatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
+                    bitsPerChannel = 32;
+                    break;
+                case SampleFormat.PcmFloat:
+                    formatFlags = kAudioFormatFlagIsFloat | kAudioFormatFlagIsPacked;
+                    bitsPerChannel = 32;
+                    break;
+                default:
+                    throw new ArgumentException($"Unsupported sample format {sampleFormat}");
+            }
+
+            uint bytesPerFrame = (bitsPerChannel / 8) * channelCount;
+
+            return new AudioStreamBasicDescription
+            {
+                SampleRate = sampleRate,
+                FormatID = kAudioFormatLinearPCM,
+                FormatFlags = formatFlags,
+                BytesPerPacket = bytesPerFrame,
+                FramesPerPacket = 1,
+                BytesPerFrame = bytesPerFrame,
+                ChannelsPerFrame = channelCount,
+                BitsPerChannel = bitsPerChannel,
+                Reserved = 0
+            };
+        }
+
+        public void Dispose()
+        {
+            GC.SuppressFinalize(this);
+            Dispose(true);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                foreach (AppleHardwareDeviceSession session in _sessions.Keys)
+                {
+                    session.Dispose();
+                }
+
+                _pauseEvent.Dispose();
+            }
+        }
+
+        public bool SupportsSampleRate(uint sampleRate)
+        {
+            return true;
+        }
+
+        public bool SupportsSampleFormat(SampleFormat sampleFormat)
+        {
+            return sampleFormat != SampleFormat.PcmInt24;
+        }
+
+        public bool SupportsChannelCount(uint channelCount)
+        {
+            if (channelCount == 6)
+            {
+                return _supportSurroundConfiguration;
+            }
+
+            return true;
+        }
+
+        public bool SupportsDirection(Direction direction)
+        {
+            return direction != Direction.Input;
+        }
+    }
+}

src/Ryujinx.Audio.Backends.Apple/AppleHardwareDeviceSession.cs

@@ -0,0 +1,285 @@
+using Ryujinx.Audio.Backends.Common;
+using Ryujinx.Audio.Common;
+using Ryujinx.Memory;
+using System;
+using System.Collections.Concurrent;
+using System.Runtime.InteropServices;
+using System.Threading;
+using System.Runtime.Versioning;
+using static Ryujinx.Audio.Backends.Apple.Native.AudioToolbox;
+
+namespace Ryujinx.Audio.Backends.Apple
+{
+    [SupportedOSPlatform("macos")]
+    [SupportedOSPlatform("ios")]
+    class AppleHardwareDeviceSession : HardwareDeviceSessionOutputBase
+    {
+        private const int NumBuffers = 3;
+
+        private readonly AppleHardwareDeviceDriver _driver;
+        private readonly ConcurrentQueue<AppleAudioBuffer> _queuedBuffers = new();
+        private readonly DynamicRingBuffer _ringBuffer = new();
+        private readonly ManualResetEvent _updateRequiredEvent;
+
+        private readonly AudioQueueOutputCallback _callbackDelegate;
+        private readonly GCHandle _gcHandle;
+
+        private IntPtr _audioQueue;
+        private readonly IntPtr[] _audioQueueBuffers = new IntPtr[NumBuffers];
+        private readonly int[] _bufferBytesFilled = new int[NumBuffers];
+
+        private readonly int _bytesPerFrame;
+
+        private ulong _playedSampleCount;
+        private bool _started;
+        private float _volume = 1f;
+
+        private readonly object _lock = new();
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        private delegate void AudioQueueOutputCallback(
+            IntPtr userData,
+            IntPtr audioQueue,
+            IntPtr buffer);
+
+        public AppleHardwareDeviceSession(
+            AppleHardwareDeviceDriver driver,
+            IVirtualMemoryManager memoryManager,
+            SampleFormat requestedSampleFormat,
+            uint requestedSampleRate,
+            uint requestedChannelCount)
+            : base(memoryManager, requestedSampleFormat, requestedSampleRate, requestedChannelCount)
+        {
+            _driver = driver;
+            _updateRequiredEvent = driver.GetUpdateRequiredEvent();
+            _callbackDelegate = OutputCallback;
+            _bytesPerFrame = BackendHelper.GetSampleSize(requestedSampleFormat) * (int)requestedChannelCount;
+
+            _gcHandle = GCHandle.Alloc(this, GCHandleType.Normal);
+
+            SetupAudioQueue();
+        }
+
+        private void SetupAudioQueue()
+        {
+            lock (_lock)
+            {
+                var format = AppleHardwareDeviceDriver.GetAudioFormat(
+                    RequestedSampleFormat,
+                    RequestedSampleRate,
+                    RequestedChannelCount);
+
+                IntPtr callbackPtr = Marshal.GetFunctionPointerForDelegate(_callbackDelegate);
+                IntPtr userData = GCHandle.ToIntPtr(_gcHandle);
+
+                int result = AudioQueueNewOutput(
+                    ref format,
+                    callbackPtr,
+                    userData,
+                    IntPtr.Zero,
+                    IntPtr.Zero,
+                    0,
+                    out _audioQueue);
+
+                if (result != 0)
+                {
+                    throw new InvalidOperationException($"AudioQueueNewOutput failed: {result}");
+                }
+
+                uint framesPerBuffer = RequestedSampleRate / 100;
+                uint bufferSize = framesPerBuffer * (uint)_bytesPerFrame;
+
+                for (int i = 0; i < NumBuffers; i++)
+                {
+                    AudioQueueAllocateBuffer(_audioQueue, bufferSize, out _audioQueueBuffers[i]);
+                    _bufferBytesFilled[i] = 0;
+
+                    PrimeBuffer(_audioQueueBuffers[i], i);
+                }
+            }
+        }
+
+        private unsafe void PrimeBuffer(IntPtr bufferPtr, int bufferIndex)
+        {
+            AudioQueueBuffer* buffer = (AudioQueueBuffer*)bufferPtr;
+
+            int capacityBytes = (int)buffer->AudioDataBytesCapacity;
+            int framesPerBuffer = capacityBytes / _bytesPerFrame;
+
+            int availableFrames = _ringBuffer.Length / _bytesPerFrame;
+            int framesToRead = Math.Min(availableFrames, framesPerBuffer);
+            int bytesToRead = framesToRead * _bytesPerFrame;
+
+            Span<byte> dst = new((void*)buffer->AudioData, capacityBytes);
+            dst.Clear();
+
+            if (bytesToRead > 0)
+            {
+                Span<byte> audio = dst.Slice(0, bytesToRead);
+                _ringBuffer.Read(audio, 0, bytesToRead);
+                ApplyVolume(buffer->AudioData, bytesToRead);
+            }
+
+            buffer->AudioDataByteSize = (uint)capacityBytes;
+            _bufferBytesFilled[bufferIndex] = bytesToRead;
+
+            AudioQueueEnqueueBuffer(_audioQueue, bufferPtr, 0, IntPtr.Zero);
+        }
+
+        private void OutputCallback(IntPtr userData, IntPtr audioQueue, IntPtr bufferPtr)
+        {
+            if (!_started || bufferPtr == IntPtr.Zero)
+                return;
+
+            int bufferIndex = Array.IndexOf(_audioQueueBuffers, bufferPtr);
+            if (bufferIndex < 0)
+                return;
+
+            int bytesPlayed = _bufferBytesFilled[bufferIndex];
+            if (bytesPlayed > 0)
+            {
+                ProcessPlayedSamples(bytesPlayed);
+            }
+
+            PrimeBuffer(bufferPtr, bufferIndex);
+        }
+
+        private void ProcessPlayedSamples(int bytesPlayed)
+        {
+            ulong samplesPlayed = GetSampleCount(bytesPlayed);
+            ulong remaining = samplesPlayed;
+            bool needUpdate = false;
+
+            while (remaining > 0 && _queuedBuffers.TryPeek(out AppleAudioBuffer buffer))
+            {
+                ulong needed = buffer.SampleCount - Interlocked.Read(ref buffer.SamplePlayed);
+                ulong take = Math.Min(needed, remaining);
+
+                ulong played = Interlocked.Add(ref buffer.SamplePlayed, take);
+                remaining -= take;
+
+                if (played == buffer.SampleCount)
+                {
+                    _queuedBuffers.TryDequeue(out _);
+                    needUpdate = true;
+                }
+
+                Interlocked.Add(ref _playedSampleCount, take);
+            }
+
+            if (needUpdate)
+            {
+                _updateRequiredEvent.Set();
+            }
+        }
+
+        private unsafe void ApplyVolume(IntPtr dataPtr, int byteSize)
+        {
+            float volume = Math.Clamp(_volume * _driver.Volume, 0f, 1f);
+            if (volume >= 0.999f)
+                return;
+
+            int sampleCount = byteSize / BackendHelper.GetSampleSize(RequestedSampleFormat);
+
+            switch (RequestedSampleFormat)
+            {
+                case SampleFormat.PcmInt16:
+                    short* s16 = (short*)dataPtr;
+                    for (int i = 0; i < sampleCount; i++)
+                        s16[i] = (short)(s16[i] * volume);
+                    break;
+
+                case SampleFormat.PcmFloat:
+                    float* f32 = (float*)dataPtr;
+                    for (int i = 0; i < sampleCount; i++)
+                        f32[i] *= volume;
+                    break;
+
+                case SampleFormat.PcmInt32:
+                    int* s32 = (int*)dataPtr;
+                    for (int i = 0; i < sampleCount; i++)
+                        s32[i] = (int)(s32[i] * volume);
+                    break;
+
+                case SampleFormat.PcmInt8:
+                    sbyte* s8 = (sbyte*)dataPtr;
+                    for (int i = 0; i < sampleCount; i++)
+                        s8[i] = (sbyte)(s8[i] * volume);
+                    break;
+            }
+        }
+
+        public override void QueueBuffer(AudioBuffer buffer)
+        {
+            _ringBuffer.Write(buffer.Data, 0, buffer.Data.Length);
+            _queuedBuffers.Enqueue(new AppleAudioBuffer(buffer.DataPointer, GetSampleCount(buffer)));
+        }
+
+        public override void Start()
+        {
+            lock (_lock)
+            {
+                if (_started)
+                    return;
+
+                _started = true;
+                AudioQueueStart(_audioQueue, IntPtr.Zero);
+            }
+        }
+
+        public override void Stop()
+        {
+            lock (_lock)
+            {
+                if (!_started)
+                    return;
+
+                _started = false;
+                AudioQueuePause(_audioQueue);
+            }
+        }
+
+        public override ulong GetPlayedSampleCount()
+            => Interlocked.Read(ref _playedSampleCount);
+
+        public override float GetVolume() => _volume;
+        public override void SetVolume(float volume) => _volume = volume;
+
+        public override bool WasBufferFullyConsumed(AudioBuffer buffer)
+        {
+            if (!_queuedBuffers.TryPeek(out AppleAudioBuffer driverBuffer))
+                return true;
+
+            return driverBuffer.DriverIdentifier != buffer.DataPointer;
+        }
+
+        public override void PrepareToClose() { }
+        public override void UnregisterBuffer(AudioBuffer buffer) { }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                Stop();
+
+                if (_audioQueue != IntPtr.Zero)
+                {
+                    AudioQueueStop(_audioQueue, true);
+                    AudioQueueDispose(_audioQueue, true);
+                    _audioQueue = IntPtr.Zero;
+                }
+
+                if (_gcHandle.IsAllocated)
+                {
+                    _gcHandle.Free();
+                }
+            }
+        }
+
+        public override void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/Ryujinx.Audio.Backends.Apple/Native/AudioToolbox.cs

@@ -0,0 +1,103 @@
+using Ryujinx.Common.Memory;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Audio.Backends.Apple.Native
+{
+    public static partial class AudioToolbox
+    {
+        [StructLayout(LayoutKind.Sequential)]
+        internal struct AudioStreamBasicDescription
+        {
+            public double SampleRate;
+            public uint FormatID;
+            public uint FormatFlags;
+            public uint BytesPerPacket;
+            public uint FramesPerPacket;
+            public uint BytesPerFrame;
+            public uint ChannelsPerFrame;
+            public uint BitsPerChannel;
+            public uint Reserved;
+        }
+
+        [StructLayout(LayoutKind.Sequential)]
+        internal struct AudioChannelLayout
+        {
+            public uint AudioChannelLayoutTag;
+            public uint AudioChannelBitmap;
+            public uint NumberChannelDescriptions;
+        }
+
+        internal const uint kAudioFormatLinearPCM = 0x6C70636D;
+        internal const uint kAudioQueueProperty_ChannelLayout = 0x6171636c;
+        internal const uint kAudioChannelLayoutTag_MPEG_5_1_A = 0x650006;
+        internal const uint kAudioFormatFlagIsFloat = (1 << 0);
+        internal const uint kAudioFormatFlagIsSignedInteger = (1 << 2);
+        internal const uint kAudioFormatFlagIsPacked = (1 << 3);
+        internal const uint kAudioFormatFlagIsBigEndian = (1 << 1);
+        internal const uint kAudioFormatFlagIsAlignedHigh = (1 << 4);
+        internal const uint kAudioFormatFlagIsNonInterleaved = (1 << 5);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueNewOutput(
+            ref AudioStreamBasicDescription format,
+            nint callback,
+            nint userData,
+            nint callbackRunLoop,
+            nint callbackRunLoopMode,
+            uint flags,
+            out nint audioQueue);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueSetProperty(
+            nint audioQueue,
+            uint propertyID,
+            ref AudioChannelLayout layout,
+            uint layoutSize);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueDispose(nint audioQueue, [MarshalAs(UnmanagedType.I1)] bool immediate);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueAllocateBuffer(
+            nint audioQueue,
+            uint bufferByteSize,
+            out nint buffer);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueStart(nint audioQueue, nint startTime);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueuePause(nint audioQueue);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueStop(nint audioQueue, [MarshalAs(UnmanagedType.I1)] bool immediate);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueSetParameter(
+            nint audioQueue,
+            uint parameterID,
+            float value);
+
+        [LibraryImport("/System/Library/Frameworks/AudioToolbox.framework/AudioToolbox")]
+        internal static partial int AudioQueueEnqueueBuffer(
+            nint audioQueue,
+            nint buffer,
+            uint numPacketDescs,
+            nint packetDescs);
+
+        [StructLayout(LayoutKind.Sequential)]
+        internal struct AudioQueueBuffer
+        {
+            public uint AudioDataBytesCapacity;
+            public nint AudioData;
+            public uint AudioDataByteSize;
+            public nint UserData;
+            public uint PacketDescriptionCapacity;
+            public nint PacketDescriptions;
+            public uint PacketDescriptionCount;
+        }
+
+        internal const uint kAudioQueueParam_Volume = 1;
+    }
+}

src/Ryujinx.Audio.Backends.Apple/Ryujinx.Audio.Backends.Apple.csproj

@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Ryujinx.Audio\Ryujinx.Audio.csproj" />
+    <ProjectReference Include="..\Ryujinx.Common\Ryujinx.Common.csproj" />
+  </ItemGroup>
+
+</Project>

src/Ryujinx.UI.Common/Configuration/AudioBackend.cs

@@ -9,5 +9,6 @@ namespace Ryujinx.UI.Common.Configuration
         OpenAl,
         SoundIo,
         SDL2,
+        AudioToolbox
     }
 }

src/Ryujinx/AppHost.cs

@@ -5,6 +5,7 @@ using Avalonia.Input;
 using Avalonia.Threading;
 using Gommon;
 using LibHac.Tools.FsSystem;
+using Ryujinx.Audio.Backends.Apple;
 using Ryujinx.Audio.Backends.Dummy;
 using Ryujinx.Audio.Backends.OpenAL;
 using Ryujinx.Audio.Backends.SDL2;
@@ -968,6 +969,9 @@ namespace Ryujinx.Ava
                 AudioBackend.Dummy,
             };
 
+            if (OperatingSystem.IsMacOS())
+                availableBackends.Insert(0, AudioBackend.AudioToolbox);
+
             AudioBackend preferredBackend = ConfigurationState.Instance.System.AudioBackend.Value;
 
             for (int i = 0; i < availableBackends.Count; i++)
@@ -1001,6 +1005,9 @@ namespace Ryujinx.Ava
 
                 deviceDriver = currentBackend switch
                 {
+#pragma warning disable CA1416 // Platform compatibility is enforced in AppleHardwareDeviceDriver.IsSupported, before any potentially platform-sensitive code can run.
+                    AudioBackend.AudioToolbox => InitializeAudioBackend<AppleHardwareDeviceDriver>(AudioBackend.AudioToolbox, nextBackend),
+#pragma warning restore CA1416
                     AudioBackend.SDL2 => InitializeAudioBackend<SDL2HardwareDeviceDriver>(AudioBackend.SDL2, nextBackend),
                     AudioBackend.SoundIo => InitializeAudioBackend<SoundIoHardwareDeviceDriver>(AudioBackend.SoundIo, nextBackend),
                     AudioBackend.OpenAl => InitializeAudioBackend<OpenALHardwareDeviceDriver>(AudioBackend.OpenAl, nextBackend),

src/Ryujinx/Assets/Locales/en_US.json

@@ -174,6 +174,7 @@
   "SettingsTabSystemAudioBackendOpenAL": "OpenAL",
   "SettingsTabSystemAudioBackendSoundIO": "SoundIO",
   "SettingsTabSystemAudioBackendSDL2": "SDL2",
+  "SettingsTabSystemAudioBackendAudioToolbox": "Apple Audio (macOS only)",
   "SettingsTabSystemCustomVSyncInterval": "Interval",
   "SettingsTabSystemHacks": "Hacks",
   "SettingsTabSystemHacksNote": "May cause instability",

src/Ryujinx/Ryujinx.csproj

@@ -50,11 +50,12 @@
   </ItemGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\Ryujinx.Audio.Backends.SDL2\Ryujinx.Audio.Backends.SDL2.csproj" />
     <ProjectReference Include="..\Ryujinx.Graphics.Vulkan\Ryujinx.Graphics.Vulkan.csproj" />
     <ProjectReference Include="..\Ryujinx.Graphics.OpenGL\Ryujinx.Graphics.OpenGL.csproj" />
     <ProjectReference Include="..\Ryujinx.Input\Ryujinx.Input.csproj" />
     <ProjectReference Include="..\Ryujinx.Input.SDL2\Ryujinx.Input.SDL2.csproj" />
+    <ProjectReference Include="..\Ryujinx.Audio.Backends.Apple\Ryujinx.Audio.Backends.Apple.csproj" />
+    <ProjectReference Include="..\Ryujinx.Audio.Backends.SDL2\Ryujinx.Audio.Backends.SDL2.csproj" />
     <ProjectReference Include="..\Ryujinx.Audio.Backends.OpenAL\Ryujinx.Audio.Backends.OpenAL.csproj" />
     <ProjectReference Include="..\Ryujinx.Audio.Backends.SoundIo\Ryujinx.Audio.Backends.SoundIo.csproj" />
     <ProjectReference Include="..\Ryujinx.Common\Ryujinx.Common.csproj" />

src/Ryujinx/UI/ViewModels/SettingsViewModel.cs

@@ -3,6 +3,7 @@ using Avalonia.Controls;
 using Avalonia.Threading;
 using CommunityToolkit.Mvvm.ComponentModel;
 using LibHac.Tools.FsSystem;
+using Ryujinx.Audio.Backends.Apple;
 using Ryujinx.Audio.Backends.OpenAL;
 using Ryujinx.Audio.Backends.SDL2;
 using Ryujinx.Audio.Backends.SoundIo;
@@ -255,6 +256,7 @@ namespace Ryujinx.Ava.UI.ViewModels
         public bool IsOpenAlEnabled { get; set; }
         public bool IsSoundIoEnabled { get; set; }
         public bool IsSDL2Enabled { get; set; }
+        public bool IsAudioToolboxEnabled { get; set; }
         public bool IsCustomResolutionScaleActive => _resolutionScale == 4;
         public bool IsScalingFilterActive => _scalingFilter == (int)Ryujinx.Common.Configuration.ScalingFilter.Fsr;
 
@@ -459,12 +461,14 @@ namespace Ryujinx.Ava.UI.ViewModels
             IsOpenAlEnabled = OpenALHardwareDeviceDriver.IsSupported;
             IsSoundIoEnabled = SoundIoHardwareDeviceDriver.IsSupported;
             IsSDL2Enabled = SDL2HardwareDeviceDriver.IsSupported;
+            IsAudioToolboxEnabled = OperatingSystem.IsMacOS() && AppleHardwareDeviceDriver.IsSupported;
 
             await Dispatcher.UIThread.InvokeAsync(() =>
             {
                 OnPropertyChanged(nameof(IsOpenAlEnabled));
                 OnPropertyChanged(nameof(IsSoundIoEnabled));
                 OnPropertyChanged(nameof(IsSDL2Enabled));
+                OnPropertyChanged(nameof(IsAudioToolboxEnabled));
             });
         }
 

src/Ryujinx/UI/Views/Settings/SettingsAudioView.axaml

@@ -45,6 +45,9 @@
                         <ComboBoxItem
                             IsEnabled="{Binding IsSDL2Enabled}"
                             Content="{locale:Locale SettingsTabSystemAudioBackendSDL2}" />
+                        <ComboBoxItem
+                            IsEnabled="{Binding IsAudioToolboxEnabled}"
+                            Content="{locale:Locale SettingsTabSystemAudioBackendAudioToolbox}" />
                     </ComboBox>
                 </StackPanel>
                 <StackPanel Margin="10,0,0,0" Orientation="Horizontal">