Fix preview music not processed correctly

Author: Raltyro

source/funkin/play/PlayState.hx

@@ -1600,9 +1600,8 @@ class PlayState extends MusicBeatSubState
       // Resume vwooshTimer
       if (!vwooshTimer.finished) vwooshTimer.active = true;
 
-      // The logic here is that if this sound doesn't auto-destroy
-      // then it's gonna be reused somewhere, so we just stop it instead.
-      forEachPausedSound(s -> needsReset ? (s.autoDestroy ? s.destroy() : s.stop()) : s.resume());
+      // Stopping a sound will kills itself anyway if s.autoDestroy is true.
+      forEachPausedSound(s -> needsReset ? s.stop() : s.resume());
 
       // Resume camera tweens if we paused any.
       for (camTween in cameraTweensPausedBySubState)

source/funkin/ui/freeplay/FreeplayState.hx

@@ -3001,7 +3001,7 @@ class FreeplayState extends MusicBeatSubState
       }
 
       if (previewMusicData == null) previewMusicData = new PreviewMusicData();
-      previewMusicData.setAssetPath(Paths.inst(previewSong.id, instSuffix), songDifficulty?.previewStart, songDifficulty?.previewEnd, true,
+      previewMusicData.setAssetPath(Paths.inst(previewSong.id, instSuffix), songDifficulty?.previewStart, songDifficulty?.previewEnd, null,
         function(musicData:PreviewMusicData)
       {
         // Check again if it's still selected.

source/funkin/ui/freeplay/components/PreviewMusicData.hx

@@ -7,6 +7,8 @@ import openfl.utils.Assets;
 import flixel.sound.FlxSoundData;
 
 #if native
+import sys.thread.Mutex;
+
 import haxe.Int64;
 import lime.media.AudioDecoder;
 import lime.utils.ArrayBuffer;
@@ -48,7 +50,7 @@ class PreviewMusicData extends FlxSoundData
     #end
   }
 
-  public function setAssetPath(path:String, startTime = 0, endTime = 15000, stream = true, ?onLoad:PreviewMusicData->Void):Void
+  public function setAssetPath(path:String, startTime = 0, endTime = 15000, ?stream:Bool, ?onLoad:PreviewMusicData->Void):Void
   {
     var cacheName = #if web 'PreviewMusicDataWeb-$path' #else 'PreviewMusicData-$path-$startTime-$endTime' #end;
 
@@ -73,20 +75,32 @@ class PreviewMusicData extends FlxSoundData
 
     audioDecoderProcess.resetDecoder(decoder, startTime, endTime);
 
-    if (stream)
+    if (stream == null) stream = FlxSoundData.allowStreaming && endTime >= FlxSoundData.streamMinimumLength;
+    if (stream && decoder.seekable())
     {
-      audioBufferProcess.bitsPerSample = audioDecoderProcess.decoder.bitsPerSample;
-      audioBufferProcess.channels = audioDecoderProcess.decoder.channels;
-      audioBufferProcess.sampleRate = audioDecoderProcess.decoder.sampleRate;
+      audioBufferProcess.bitsPerSample = audioDecoderProcess.bitsPerSample;
+      audioBufferProcess.channels = audioDecoderProcess.channels;
+      audioBufferProcess.sampleRate = audioDecoderProcess.sampleRate;
       buffer = audioBufferProcess;
+
+      if (onLoad != null) onLoad(this);
     }
     else
     {
-      buffer = AudioBuffer.fromDecoder(audioDecoderProcess, false, false);
+      buffer = new AudioBuffer();
+      buffer.decoder = audioDecoderProcess;
+      buffer.loadAsync((_) -> {
+        buffer.decoder = null;
+
+        //var output = sys.io.File.write("../../../../tempPartial.dat", true);
+        //output.writeBytes(buffer.data.buffer, 0, buffer.data.byteLength);
+        //output.close();
+
+        if (onLoad != null) onLoad(this);
+      });
+
       FlxSoundData.fromAudioBuffer(buffer, cacheName, true);
     }
-
-    if (onLoad != null) onLoad(this);
     #elseif web
     // In web, use FlxPartialSound...
     // hardcode it to use percentage from 0 to 0.2
@@ -95,11 +109,12 @@ class PreviewMusicData extends FlxSoundData
     var promise = FlxPartialSound.partialLoadFromFile(Paths.stripLibrary(path), 0, 0.2);
     if (promise == null) return;
 
+    @:privateAccess
+    var soundData = FlxSoundData.createSoundData(null, cacheName, true);
+
     promise.future.onComplete(function(partialSound)
     @:privateAccess {
-      buffer = @:privateAccess partialSound.__buffer;
-      FlxSoundData.fromAudioBuffer(buffer, cacheName, true);
-
+      soundData.buffer = buffer = partialSound.__buffer;
       if (buffer.__srcAudioBuffer != null)
       {
         processFading(buffer.__srcAudioBuffer);
@@ -174,15 +189,19 @@ private class PreviewMusicDecoder extends AudioDecoder
   var bufferInt8View:Int8Array;
   var bufferInt16View:Int16Array;
   var bufferInt32View:Int32Array;
+  var mutex:Mutex;
 
   public function new(parent:PreviewMusicData)
   {
     super();
     this.parent = parent;
+    mutex = new Mutex();
   }
 
   public function resetDecoder(decoder:AudioDecoder, startTime:Float, endTime:Float):Void
   {
+    mutex.acquire();
+
     var oldDecoder = this.decoder;
     if (oldDecoder != null) oldDecoder.dispose();
 
@@ -213,6 +232,8 @@ private class PreviewMusicDecoder extends AudioDecoder
 
       rewind();
     }
+
+    mutex.release();
   }
 
   override function clone():PreviewMusicDecoder
@@ -229,6 +250,8 @@ private class PreviewMusicDecoder extends AudioDecoder
   {
     if (decoder == null) return 0;
 
+    mutex.acquire();
+
     var currentSampleOffset = decoder.tell() - startSamples;
     var remainingBytes = (endSamples - currentSampleOffset) * channels * byteRate;
 
@@ -244,32 +267,43 @@ private class PreviewMusicDecoder extends AudioDecoder
       eof = decoder.eof;
     }
 
-    if (byteRate == 3) return result;
+    if (byteRate == 3)
+    {
+      mutex.release();
+      return result;
+    }
 
+    // Fading processing
     if (bufferView.buffer != buffer) bufferView.initBuffer(buffer);
 
-    var i = 0;
-    var channel = 0;
-    var length = Std.int(result / byteRate);
-    while (i < length)
+    pos = Std.int(pos / byteRate);
+    len = pos + Std.int(result / byteRate);
+    var channel = 0, b:Int;
+    while (pos < len)
     {
       if (currentSampleOffset < fadeStartSamples)
       {
         switch (byteRate)
         {
-          case 1: bufferInt8View[i] = Std.int(bufferInt8View[i] * currentSampleOffset.low / fadeStartSamples.low);
-          case 2: bufferInt16View[i] = Std.int(bufferInt16View[i] * currentSampleOffset.low / fadeStartSamples.low);
-          case 4: bufferInt32View[i] = Std.int(bufferInt32View[i] * currentSampleOffset.low / fadeStartSamples.low);
+          case 1:
+            bufferInt8View[pos] = Std.int(bufferInt8View[pos] * (currentSampleOffset.low / fadeStartSamples.low).clamp(0, 1));
+          case 2:
+            bufferInt16View[pos] = Std.int(bufferInt16View[pos] * (currentSampleOffset.low / fadeStartSamples.low).clamp(0, 1));
+          case 4:
+            bufferInt32View[pos] = Std.int(bufferInt32View[pos] * (currentSampleOffset.low / fadeStartSamples.low).clamp(0, 1));
           default:
         }
       }
       else if (currentSampleOffset > fadeEndStartSampleOffset)
       {
         switch (byteRate)
         {
-          case 1: bufferInt8View[i] = Std.int(bufferInt8View[i] * (fadeEndEndSampleOffset - currentSampleOffset).low / fadeStartSamples.low);
-          case 2: bufferInt16View[i] = Std.int(bufferInt16View[i] * (fadeEndEndSampleOffset - currentSampleOffset).low / fadeStartSamples.low);
-          case 4: bufferInt32View[i] = Std.int(bufferInt32View[i] * (fadeEndEndSampleOffset - currentSampleOffset).low / fadeStartSamples.low);
+          case 1:
+            bufferInt8View[pos] = Std.int(bufferInt8View[pos] * ((fadeEndEndSampleOffset - currentSampleOffset).low / fadeEndSamples.low).clamp(0, 1));
+          case 2:
+            bufferInt16View[pos] = Std.int(bufferInt16View[pos] * ((fadeEndEndSampleOffset - currentSampleOffset).low / fadeEndSamples.low).clamp(0, 1));
+          case 4:
+            bufferInt32View[pos] = Std.int(bufferInt32View[pos] * ((fadeEndEndSampleOffset - currentSampleOffset).low / fadeEndSamples.low).clamp(0, 1));
           default:
         }
       }
@@ -279,9 +313,11 @@ private class PreviewMusicDecoder extends AudioDecoder
         channel = 0;
         currentSampleOffset++;
       }
-      i++;
+      pos++;
     }
 
+    mutex.release();
+
     return result;
   }