fixup! Port XAudio to Silk.NET

Author: Jklawreszuk

sources/engine/Stride.Audio/Layers/XAudio/AudioProvider.cs

@@ -3,6 +3,7 @@
 #if WINDOWS
 
 using System;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using Silk.NET.Core.Native;
 using Silk.NET.XAudio;
@@ -183,8 +184,10 @@ public unsafe Source SourceCreate(Listener listener, int sampleRate, int maxNumb
             pcmWaveFormat.WBitsPerSample = 16;
 			pcmWaveFormat.NBlockAlign = (ushort)(pcmWaveFormat.NChannels * pcmWaveFormat.WBitsPerSample / 8);
 
-
-            int result = listener.device.xAudio->CreateSourceVoice(ref source.sourceVoice, &pcmWaveFormat, 0, XAUDIO2_MAX_FREQ_RATIO, null, null, null);
+            dynamic d = source;
+            IXAudio2VoiceCallback callback = d;
+            
+            int result = listener.device.xAudio->CreateSourceVoice(ref source.sourceVoice, &pcmWaveFormat, 0, XAUDIO2_MAX_FREQ_RATIO, ref callback, null, null);
             if (HResult.IndicatesFailure(result))
             {
                 return null;

sources/engine/Stride.Audio/Layers/XAudio/Source.cs

@@ -1,14 +1,15 @@
 // Copyright (c) .NET Foundation and Contributors (https://dotnetfoundation.org/ & https://stride3d.net) and Silicon Studio Corp. (https://www.siliconstudio.co.jp)
 // Distributed under the MIT license. See the LICENSE.md file in the project root for more information.
 #if WINDOWS
+using System.Runtime.InteropServices;
 using Silk.NET.XAudio;
 using Stride.Audio.Layers.XAudio;
+using Buffer = Silk.NET.XAudio.Buffer;
 
 namespace Stride.Audio;
 
 public sealed unsafe partial class Source
 {
-    public IXAudio2VoiceCallback value = new();
     public IXAudio2MasteringVoice* masteringVoice;
     public IXAudio2SourceVoice* sourceVoice;
     public X3DAudioEmitter emitter;
@@ -27,9 +28,78 @@ public sealed unsafe partial class Source
 
     public volatile int samplesAtBegin = 0; 
 
-    public unsafe void GetState(VoiceState* state)
+    public void GetState(VoiceState* state)
     {
         sourceVoice->GetState(state, 0);
     }
+    
+    public void OnVoiceProcessingPassStart(uint BytesRequired) {}
+    public void OnVoiceProcessingPassEnd() {}
+    
+    public void OnStreamEnd()
+    {
+        if (playing)
+        {
+            if (Streamed)
+            {
+                //buffer was flagged as end of stream
+                //looping is handled by the streamer, in the top level layer
+                new AudioProvider().SourceStop(this);
+            }
+            else if (!looped)
+            {
+                playing = false;
+                pause = false;
+            }
+        }
+    }
+
+    public void OnBufferStart(void* pBufferContext)
+    {
+        if (Streamed)
+        {
+            var buffer = Marshal.PtrToStructure<AudioBuffer>(new(pBufferContext));
+
+            if (buffer.Type == BufferType.BeginOfStream)
+            {
+                //we need this info to compute position of stream
+                VoiceState state;
+                GetState(&state);
+
+                samplesAtBegin = (int)state.SamplesPlayed;
+            }
+        }
+    }
+    
+    public void OnBufferEnd(void* pBufferContext)
+    {
+        if (Streamed)
+        {
+            var buffer = Marshal.PtrToStructure<AudioBuffer>(new(pBufferContext));
+
+            for (int i = 0; i < freeBuffersMax; i++)
+            {
+                if (freeBuffers[i] == null)
+                {
+                    freeBuffers[i] = buffer;
+                    break;
+                }
+            }
+
+        }	
+    }
+    
+    public void OnLoopEnd(void* pBufferContext)
+    {
+        if (!Streamed)
+        {
+            VoiceState state;
+            GetState(&state);
+
+            samplesAtBegin = (int)state.SamplesPlayed;
+        }
+    }
+    
+    public void OnVoiceError(void* pBufferContext, int Error) { }
 }
 #endif