Звуковой плеер: запуск, пауза и положение

using System;
using System.Buffers.Binary;
using Reckfell;

public static class DemoTone
{
    public static AudioStreamWav Create(float frequency = 440, double seconds = .3,
        float amplitude = .15f, bool loop = false)
    {
        const int rate = 22050;
        if (!float.IsFinite(frequency) || frequency <= 0 || frequency >= rate / 2f ||
            !double.IsFinite(seconds) || seconds < .02 || seconds > 30 ||
            !float.IsFinite(amplitude) || amplitude < 0 || amplitude > 1)
            throw new ArgumentOutOfRangeException(nameof(frequency), "Invalid teaching-tone parameters.");
        int count = (int)(seconds * rate);
        byte[] data = new byte[count * 2];
        for (int i = 0; i < count; i++)
        {
            double fade = Math.Min(1, Math.Min(i, count - 1 - i) / (rate * .005));
            short value = (short)(Math.Sin(2 * Math.PI * frequency * i / rate) * amplitude * fade * short.MaxValue);
            BinaryPrimitives.WriteInt16LittleEndian(data.AsSpan(i * 2, 2), value);
        }
        return new AudioStreamWav
        {
            Format = AudioStreamWav.FormatEnum.Format16Bits, MixRate = rate, Stereo = false,
            Data = data, LoopMode = loop ? AudioStreamWav.LoopModeEnum.Forward : AudioStreamWav.LoopModeEnum.Disabled,
            LoopBegin = 0, LoopEnd = count
        };
    }
}

using System;
using Reckfell;

public partial class SoundDemo : Control
{
    public AudioStreamPlayer Voice { get; private set; } = null!;
    public int FinishedCount { get; private set; }
    public Label Status { get; private set; } = null!;
    private bool _ru;
    private string Text(string ru, string en) => _ru ? ru : en;

    public override void _Ready()
    {
        _ru = TranslationServer.GetLocale().StartsWith("ru", StringComparison.OrdinalIgnoreCase);
        Voice = new AudioStreamPlayer
        {
            Name = "Voice", Stream = DemoTone.Create(seconds: 1), MaxPolyphony = 1,
            PlaybackType = AudioServer.PlaybackType.Stream
        };
        AddChild(Voice);
        var layout = new VBoxContainer { Position = new Vector2(24, 24) }; AddChild(layout);
        Status = new Label { Text = Text("Готово", "Ready") }; layout.AddChild(Status);
        AddButton(layout, Text("Запустить заново", "Restart"), Restart);
        AddButton(layout, Text("Пауза", "Pause"), () => SetPaused(true));
        AddButton(layout, Text("Продолжить", "Resume"), () => SetPaused(false));
        AddButton(layout, Text("Остановить", "Stop"), StopSound);
        Voice.Finished += () => { FinishedCount++; Status.Text = Text("Завершено", "Finished"); };
    }

    private static void AddButton(VBoxContainer parent, string text, Action action)
    {
        var button = new Button { Text = text }; parent.AddChild(button); button.Pressed += action;
    }

    public void Restart()
    {
        Voice.Stop(); Voice.Play();
        Status.Text = Text("Воспроизведение", "Playing");
    }

    public void SetPaused(bool paused)
    {
        if (!Voice.IsPlaying() && !Voice.StreamPaused) return;
        Voice.StreamPaused = paused;
        Status.Text = paused ? Text("Пауза", "Paused") : Text("Воспроизведение", "Playing");
    }

    public void StopSound()
    {
        Voice.Stop(); Status.Text = Text("Остановлено", "Stopped");
    }
}

using Reckfell;

public partial class SpatialSound2D : Entity2D
{
    public AudioListener2D Listener { get; private set; } = null!;
    public AudioStreamPlayer2D Source { get; private set; } = null!;

    public override void _Ready()
    {
        GetViewport().AudioListenerEnable2D = true;
        Listener = new AudioListener2D { Name = "Listener", Position = new Vector2(256, 144) };
        AddChild(Listener); Listener.MakeCurrent();
        Source = new AudioStreamPlayer2D
        {
            Name = "Source", Position = new Vector2(100, 144), Stream = DemoTone.Create(loop: true),
            MaxDistance = 600, Attenuation = 1, PanningStrength = 2,
            PlaybackType = AudioServer.PlaybackType.Stream
        };
        AddChild(Source); Source.Play();
    }

    public override void _Process(double delta)
    {
        Source.Position += Input.GetVector("ui_left", "ui_right", "ui_up", "ui_down") * 160 * (float)delta;
        QueueRedraw();
    }

    public override void _Draw()
    {
        if (Source is null || Listener is null) return;
        DrawCircle(Listener.Position, 8, Colors.White);
        DrawCircle(Source.Position, 8, new Color(.15f, .35f, 1));
        DrawLine(Listener.Position, Source.Position, new Color(.4f, .4f, .4f), 1);
    }
}

using Reckfell;

public partial class SpatialSound3D : Entity3D
{
    public AudioListener3D Listener { get; private set; } = null!;
    public AudioStreamPlayer3D Source { get; private set; } = null!;

    public override void _Ready()
    {
        GetViewport().AudioListenerEnable3D = true;
        Listener = new AudioListener3D { Name = "Listener" }; AddChild(Listener); Listener.MakeCurrent();
        Source = new AudioStreamPlayer3D
        {
            Name = "Source", Position = new Vector3(3, 0, -3), Stream = DemoTone.Create(loop: true),
            UnitSize = 1, MaxDistance = 30, PanningStrength = 1,
            AttenuationFilterDb = 0, PlaybackType = AudioServer.PlaybackType.Stream
        };
        AddChild(Source);
        var material = new StandardMaterial3D
        {
            ShadingMode = BaseMaterial3D.ShadingModeEnum.Unshaded,
            AlbedoColor = new Color(.15f, .35f, 1)
        };
        Source.AddChild(new MeshInstance3D { Mesh = new SphereMesh { Radius = .2f, Height = .4f }, MaterialOverride = material });
        var camera = new Camera3D { Position = new Vector3(0, 6, 10) }; AddChild(camera);
        camera.LookAt(Vector3.Zero); camera.MakeCurrent();
        Source.Play();
    }

    public override void _Process(double delta)
    {
        Vector2 move = Input.GetVector("ui_left", "ui_right", "ui_up", "ui_down");
        Source.Position += new Vector3(move.X, 0, move.Y) * 4 * (float)delta;
    }
}