Add OpenAL sound output.

XAudio2: Some stuff I forgot to dispose.

BizHawk.Client.Common/config/Config.cs

@@ -111,7 +111,7 @@ namespace BizHawk.Client.Common
 
 		public enum EDispMethod { OpenGL, GdiPlus, SlimDX9 };
 
-		public enum ESoundOutputMethod { DirectSound, XAudio2, Dummy };
+		public enum ESoundOutputMethod { DirectSound, XAudio2, OpenAL, Dummy };
 
 		public enum EDispManagerAR { None, System, Custom };
 

BizHawk.Client.EmuHawk/BizHawk.Client.EmuHawk.csproj

@@ -625,6 +625,7 @@
     </Compile>
     <Compile Include="Sound\Output\DirectSoundSoundOutput.cs" />
     <Compile Include="Sound\Output\DummySoundOutput.cs" />
+    <Compile Include="Sound\Output\OpenALSoundOutput.cs" />
     <Compile Include="Sound\Output\XAudio2SoundOutput.cs" />
     <Compile Include="Sound\Sound.cs" />
     <Compile Include="Sound\Utilities\SoundOutputProvider.cs" />

BizHawk.Client.EmuHawk/MainForm.cs

@@ -276,6 +276,9 @@ namespace BizHawk.Client.EmuHawk
 			Global.ActiveController = Global.NullControls;
 			Global.AutoFireController = Global.AutofireNullControls;
 			Global.AutofireStickyXORAdapter.SetOnOffPatternFromConfig();
+#if !WINDOWS
+			Global.Config.SoundOutputMethod = Config.ESoundOutputMethod.OpenAL;
+#endif
 			try { GlobalWin.Sound = new Sound(Handle); }
 			catch
 			{

BizHawk.Client.EmuHawk/Sound/Output/OpenALSoundOutput.cs

@@ -0,0 +1,177 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+using OpenTK.Audio;
+using OpenTK.Audio.OpenAL;
+
+using BizHawk.Client.Common;
+
+namespace BizHawk.Client.EmuHawk
+{
+	public class OpenALSoundOutput : ISoundOutput
+	{
+		private bool _disposed;
+		private Sound _sound;
+		private AudioContext _context;
+		private int _sourceID;
+		private BufferPool _bufferPool;
+		private long _runningSamplesPlayed;
+		private long _runningSamplesQueued;
+
+		public OpenALSoundOutput(Sound sound)
+		{
+			_sound = sound;
+			_context = new AudioContext();
+		}
+
+		public void Dispose()
+		{
+			if (_disposed) return;
+
+			_context.Dispose();
+			_context = null;
+
+			_disposed = true;
+		}
+
+		public static IEnumerable<string> GetDeviceNames()
+		{
+			return Enumerable.Empty<string>();
+		}
+
+		private int BufferSizeSamples { get; set; }
+
+		public int MaxSamplesDeficit { get; private set; }
+
+		public void ApplyVolumeSettings(double volume)
+		{
+			AL.Source(_sourceID, ALSourcef.Gain, (float)volume);
+		}
+
+		public void StartSound()
+		{
+			BufferSizeSamples = Sound.MillisecondsToSamples(Global.Config.SoundBufferSizeMs);
+			MaxSamplesDeficit = BufferSizeSamples;
+
+			_sourceID = AL.GenSource();
+
+			_bufferPool = new BufferPool();
+			_runningSamplesQueued = 0;
+		}
+
+		public void StopSound()
+		{
+			AL.SourceStop(_sourceID);
+
+			AL.DeleteSource(_sourceID);
+
+			_bufferPool.Dispose();
+			_bufferPool = null;
+
+			BufferSizeSamples = 0;
+		}
+
+		public int CalculateSamplesNeeded()
+		{
+			bool isInitializing = _runningSamplesQueued == 0;
+			bool detectedUnderrun = !isInitializing && GetSource(ALGetSourcei.BuffersProcessed) == GetSource(ALGetSourcei.BuffersQueued);
+			if (detectedUnderrun)
+			{
+				_sound.OnUnderrun();
+			}
+			UnqueueProcessedBuffers();
+			long samplesAwaitingPlayback = _runningSamplesQueued - (_runningSamplesPlayed + GetSource(ALGetSourcei.SampleOffset));
+			int samplesNeeded = (int)Math.Max(BufferSizeSamples - samplesAwaitingPlayback, 0);
+			if (isInitializing || detectedUnderrun)
+			{
+				_sound.HandleInitializationOrUnderrun(detectedUnderrun, ref samplesNeeded);
+			}
+			return samplesNeeded;
+		}
+
+		public void WriteSamples(short[] samples, int sampleCount)
+		{
+			if (sampleCount == 0) return;
+			UnqueueProcessedBuffers();
+			int byteCount = sampleCount * Sound.BlockAlign;
+			var buffer = _bufferPool.Obtain(byteCount);
+			AL.BufferData(buffer.BufferID, ALFormat.Stereo16, samples, byteCount, Sound.SampleRate);
+			AL.SourceQueueBuffer(_sourceID, buffer.BufferID);
+			_runningSamplesQueued += sampleCount;
+			if (AL.GetSourceState(_sourceID) != ALSourceState.Playing)
+			{
+				AL.SourcePlay(_sourceID);
+			}
+		}
+
+		private void UnqueueProcessedBuffers()
+		{
+			int releaseCount = GetSource(ALGetSourcei.BuffersProcessed);
+			while (releaseCount > 0)
+			{
+				AL.SourceUnqueueBuffer(_sourceID);
+				var releasedBuffer = _bufferPool.ReleaseOne();
+				_runningSamplesPlayed += releasedBuffer.Length / Sound.BlockAlign;
+				releaseCount--;
+			}
+		}
+
+		private int GetSource(ALGetSourcei param)
+		{
+			int value;
+			AL.GetSource(_sourceID, param, out value);
+			return value;
+		}
+
+		private class BufferPool : IDisposable
+		{
+			private List<BufferPoolItem> _availableItems = new List<BufferPoolItem>();
+			private Queue<BufferPoolItem> _obtainedItems = new Queue<BufferPoolItem>();
+
+			public void Dispose()
+			{
+				foreach (BufferPoolItem item in _availableItems.Concat(_obtainedItems))
+				{
+					AL.DeleteBuffer(item.BufferID);
+				}
+				_availableItems.Clear();
+				_obtainedItems.Clear();
+			}
+
+			public BufferPoolItem Obtain(int length)
+			{
+				BufferPoolItem item = GetAvailableItem() ?? new BufferPoolItem();
+				item.Length = length;
+				_obtainedItems.Enqueue(item);
+				return item;
+			}
+
+			private BufferPoolItem GetAvailableItem()
+			{
+				if (_availableItems.Count == 0) return null;
+				BufferPoolItem item = _availableItems[0];
+				_availableItems.RemoveAt(0);
+				return item;
+			}
+
+			public BufferPoolItem ReleaseOne()
+			{
+				BufferPoolItem item = _obtainedItems.Dequeue();
+				_availableItems.Add(item);
+				return item;
+			}
+
+			public class BufferPoolItem
+			{
+				public int BufferID { get; private set; }
+				public int Length { get; set; }
+
+				public BufferPoolItem()
+				{
+					BufferID = AL.GenBuffer();
+				}
+			}
+		}
+	}
+}

BizHawk.Client.EmuHawk/Sound/Output/XAudio2SoundOutput.cs

@@ -92,6 +92,7 @@ namespace BizHawk.Client.EmuHawk
 			_sourceVoice.Dispose();
 			_sourceVoice = null;
 
+			_bufferPool.Dispose();
 			_bufferPool = null;
 
 			BufferSizeSamples = 0;
@@ -129,11 +130,21 @@ namespace BizHawk.Client.EmuHawk
 			_runningSamplesQueued += sampleCount;
 		}
 
-		private class BufferPool
+		private class BufferPool : IDisposable
 		{
 			private List<BufferPoolItem> _availableItems = new List<BufferPoolItem>();
 			private Queue<BufferPoolItem> _obtainedItems = new Queue<BufferPoolItem>();
 
+			public void Dispose()
+			{
+				foreach (BufferPoolItem item in _availableItems.Concat(_obtainedItems))
+				{
+					item.DataStream.Dispose();
+				}
+				_availableItems.Clear();
+				_obtainedItems.Clear();
+			}
+
 			public BufferPoolItem Obtain(int length)
 			{
 				BufferPoolItem item = GetAvailableItem(length) ?? new BufferPoolItem(length);

BizHawk.Client.EmuHawk/Sound/Sound.cs

@@ -25,13 +25,16 @@ namespace BizHawk.Client.EmuHawk
 #if WINDOWS
 			if (Global.Config.SoundOutputMethod == Config.ESoundOutputMethod.DirectSound)
 				_soundOutput = new DirectSoundSoundOutput(this, mainWindowHandle);
-			else if (Global.Config.SoundOutputMethod == Config.ESoundOutputMethod.XAudio2)
+
+			if (Global.Config.SoundOutputMethod == Config.ESoundOutputMethod.XAudio2)
 				_soundOutput = new XAudio2SoundOutput(this);
-			else
-				_soundOutput = new DummySoundOutput(this);
-#else
-			_soundOutput = new DummySoundOutput(this);
 #endif
+
+			if (Global.Config.SoundOutputMethod == Config.ESoundOutputMethod.OpenAL)
+				_soundOutput = new OpenALSoundOutput(this);
+
+			if (_soundOutput == null)
+				_soundOutput = new DummySoundOutput(this);
 		}
 
 		public void Dispose()

BizHawk.Client.EmuHawk/config/SoundConfig.cs

@@ -67,8 +67,10 @@ namespace BizHawk.Client.EmuHawk
 		private void PopulateDeviceList()
 		{
 			IEnumerable<string> deviceNames = Enumerable.Empty<string>();
+#if WINDOWS
 			if (rbOutputMethodDirectSound.Checked) deviceNames = DirectSoundSoundOutput.GetDeviceNames();
 			if (rbOutputMethodXAudio2.Checked) deviceNames = XAudio2SoundOutput.GetDeviceNames();
+#endif
 			listBoxSoundDevices.Items.Clear();
 			listBoxSoundDevices.Items.Add("<default>");
 			listBoxSoundDevices.SelectedIndex = 0;