optimize audio resource tracking

src/Audio/AudioDevice.cs

@@ -27,8 +27,8 @@ namespace MoonWorks.Audio
 			}
 		}
 
-		private readonly List<WeakReference<AudioResource>> resources = new List<WeakReference<AudioResource>>();
+		private readonly HashSet<WeakReference> resources = new HashSet<WeakReference>();
-		private readonly List<StreamingSound> streamingSounds = new List<StreamingSound>();
+		private readonly HashSet<WeakReference> streamingSoundReferences = new HashSet<WeakReference>();
 
 		private AudioTweenPool AudioTweenPool = new AudioTweenPool();
 		private readonly List<AudioTween> AudioTweens = new List<AudioTween>();
@@ -150,9 +150,17 @@ namespace MoonWorks.Audio
 			previousTickTime = TickStopwatch.Elapsed.Ticks;
 			float elapsedSeconds = (float) tickDelta / System.TimeSpan.TicksPerSecond;
 
-			for (var i = streamingSounds.Count - 1; i >= 0; i--)
+			foreach (var weakReference in streamingSoundReferences)
 			{
-				streamingSounds[i].Update();
+				var target = weakReference.Target;
+				if (target == null)
+				{
+					streamingSoundReferences.Remove(weakReference);
+				}
+				else
+				{
+					(target as StreamingSound).Update();
+				}
 			}
 
 			for (var i = AudioTweens.Count - 1; i >= 0; i--)
@@ -252,21 +260,11 @@ namespace MoonWorks.Audio
 			WakeSignal.Set();
 		}
 
-		private void AddDynamicSoundInstance(StreamingSound instance)
+		internal void AddResourceReference(AudioResource resource)
-		{
-			streamingSounds.Add(instance);
-		}
-
-		private void RemoveDynamicSoundInstance(StreamingSound reference)
-		{
-			streamingSounds.Remove(reference);
-		}
-
-		internal void AddResourceReference(AudioResource resource, WeakReference<AudioResource> resourceReference)
 		{
 			lock (StateLock)
 			{
-				resources.Add(resourceReference);
+				resources.Add(resource.weakReference);
 
 				if (resource is StreamingSound streamingSound)
 				{
@@ -275,11 +273,11 @@ namespace MoonWorks.Audio
 			}
 		}
 
-		internal void RemoveResourceReference(AudioResource resource, WeakReference<AudioResource> resourceReference)
+		internal void RemoveResourceReference(AudioResource resource)
 		{
 			lock (StateLock)
 			{
-				resources.Remove(resourceReference);
+				resources.Remove(resource.weakReference);
 
 				if (resource is StreamingSound streamingSound)
 				{
@@ -288,6 +286,16 @@ namespace MoonWorks.Audio
 			}
 		}
 
+		private void AddDynamicSoundInstance(StreamingSound instance)
+		{
+			streamingSoundReferences.Add(instance.weakReference);
+		}
+
+		private void RemoveDynamicSoundInstance(StreamingSound instance)
+		{
+			streamingSoundReferences.Remove(instance.weakReference);
+		}
+
 		protected virtual void Dispose(bool disposing)
 		{
 			if (!IsDisposed)
@@ -296,13 +304,13 @@ namespace MoonWorks.Audio
 				{
 					if (disposing)
 					{
-						for (var i = resources.Count - 1; i >= 0; i--)
+						foreach (var weakReference in resources)
 						{
-							var weakReference = resources[i];
+							var target = weakReference.Target;
 
-							if (weakReference.TryGetTarget(out var resource))
+							if (target != null)
 							{
-								resource.Dispose();
+								(target as IDisposable).Dispose();
 							}
 						}
 						resources.Clear();

src/Audio/AudioResource.cs

@@ -8,14 +8,14 @@ namespace MoonWorks.Audio
 
 		public bool IsDisposed { get; private set; }
 
-		private WeakReference<AudioResource> selfReference;
+		internal WeakReference weakReference;
 
 		public AudioResource(AudioDevice device)
 		{
 			Device = device;
 
-			selfReference = new WeakReference<AudioResource>(this);
+			weakReference = new WeakReference(this);
-			Device.AddResourceReference(this, selfReference);
+			Device.AddResourceReference(this);
 		}
 
 		protected abstract void Destroy();
@@ -26,10 +26,10 @@ namespace MoonWorks.Audio
 			{
 				Destroy();
 
-				if (selfReference != null)
+				if (weakReference != null)
 				{
-					Device.RemoveResourceReference(this, selfReference);
+					Device.RemoveResourceReference(this);
-					selfReference = null;
+					weakReference = null;
 				}
 
 				IsDisposed = true;