Adjusting `AlgorithmicReverbModifier`'s `RoomSize` and `Damp` Properties Causes Exceptions

[Mioter]

After switching to the source code, the previously reported Seek()-related issue no longer occurs. Therefore, this issue has been updated to reflect the current problem.

However, adjusting the RoomSize and Damp properties of the AlgorithmicReverbModifier during playback still throws an exception.

Exception Stack Trace:

System.NullReferenceException: Object reference not set to an instance of an object.  
   at SoundFlow.Modifiers.AlgorithmicReverbModifier.ProcessSample(Single sample, Int32 channel) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Modifiers\AlgorithmicReverbModifier.cs:line 285  
   at SoundFlow.Abstracts.SoundModifier.Process(Span`1 buffer) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Abstracts\SoundModifier.cs:line 27  
   at SoundFlow.Abstracts.SoundComponent.Process(Span`1 outputBuffer) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Abstracts\SoundComponent.cs:line 322  
   at SoundFlow.Components.Mixer.GenerateAudio(Span`1 buffer) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Components\Mixer.cs:line 89  
   at SoundFlow.Abstracts.SoundComponent.Process(Span`1 outputBuffer) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Abstracts\SoundComponent.cs:line 300  
   at SoundFlow.Abstracts.AudioEngine.ProcessGraph(IntPtr output, Int32 length) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Abstracts\AudioEngine.cs:line 239  
   at SoundFlow.Backends.MiniAudio.MiniAudioEngine.AudioCallback(IntPtr _, IntPtr output, IntPtr input, UInt32 length) in D:\QAQ\Project\Avalonia\QwQ Music\Src\Backends\MiniAudio\MiniAudioEngine.cs:line 86  

[LSXPrime]

I apologize for the delayed response. I was unable to reproduce the issue using either SoundPlayer or Oscillator in the following example:

    public static void Run()
    {
        // 1. Initialize AudioEngine
        var audioEngine = new MiniAudioEngine(44100, Capability.Playback);
        Console.WriteLine("SoundFlow Audio Engine initialized with MiniAudio backend.");
            
        // 2. Create a SoundPlayer 
        var soundPlayer = new SoundPlayer(new StreamDataProvider(File.OpenRead(@"D:\Music\Personal Collection\尹昔眠 - Can't Escape Reincarnation.mp3")));
        
        // 3. Create AlgorithmicReverbModifier
        var reverbModifier = new AlgorithmicReverbModifier();

        // 4. Add ReverbModifier to the SoundPlayer's modifiers
        soundPlayer.AddModifier(reverbModifier);
        
        // 5. Connect SoundPlayer to the Master Mixer input
        Mixer.Master.AddComponent(soundPlayer);
        
        soundPlayer.Play();


        Console.WriteLine("AlgorithmicReverbModifier added to SoundPlayer.");
        Console.WriteLine("Starting playback. Press 'P' to play and pause, 'R' to change RoomSize, 'D' to change Damp, 'Q' to quit.");


        while (true)
        {
            if (Console.KeyAvailable)
            {
                var keyInfo = Console.ReadKey(true);

                switch (keyInfo.Key)
                {
                    case ConsoleKey.P:
                        if (soundPlayer.State == PlaybackState.Playing)
                        {
                            soundPlayer.Pause();
                            Console.WriteLine("Playback paused.");
                        }
                        else
                        {
                            soundPlayer.Play();
                            Console.WriteLine("Playback started.");
                        }
                        break;

                    case ConsoleKey.R:
                        Console.Write("Enter new RoomSize (0-1): ");
                        if (float.TryParse(Console.ReadLine(), out var newRoomSize))
                        {
                            reverbModifier.RoomSize = newRoomSize;
                            Console.WriteLine($"RoomSize set to: {newRoomSize}");
                        }
                        else
                        {
                            Console.WriteLine("Invalid RoomSize value.");
                        }
                        break;

                    case ConsoleKey.D:
                        Console.Write("Enter new Damp (0-1): ");
                        if (float.TryParse(Console.ReadLine(), out var newDamp))
                        {
                            reverbModifier.Damp = newDamp;
                            Console.WriteLine($"Damp set to: {newDamp}");
                        }
                        else
                        {
                            Console.WriteLine("Invalid Damp value.");
                        }
                        break;

                    case ConsoleKey.Q:
                        Console.WriteLine("Quitting.");
                        return;

                    default:
                        Console.WriteLine("Invalid command.");
                        break;
                }
            }
        }
    }

It works fine with sine waves and actual audio data, so it's unlikely to be a data issue. Would you mind sharing a minimal reproducible example?

[Mioter]

The sample code may not exhibit issues because it doesn’t adjust parameter values rapidly. This problem is triggered in my case when I quickly drag sliders to modify RoomSize and Damp.

The root cause is likely that adjusting these properties calls UpdateParameters(), which reinitializes the comb filters. This could lead to ProcessSample() accessing uninitialized filters, resulting in the exception.

Solution: Implementing UpdateCombFilterParameters() to update comb filter parameters without recreating the filters resolved the issue. Thank you! ヾ(≧▽≦*)o

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity.
It will be closed if no further activity occurs.

If this issue is still relevant, please leave a comment indicating that you would like it to remain open.
Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity.
It will be closed if no further activity occurs.

If this issue is still relevant, please leave a comment indicating that you would like it to remain open.
Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity.
It will be closed if no further activity occurs.

If this issue is still relevant, please leave a comment indicating that you would like it to remain open.
Thank you for your contributions.

[LSXPrime]

Hello, thanks for elaboration, the issue has been fixed in the latest update (v1.0.4). Please update the SoundFlow package from NuGet.