Add streaming camera listener in userspace

Author: Banane9

ShowmanTools/LinuxStreamingAudioFix.cs

@@ -2,15 +2,52 @@
 using FrooxEngine;
 using HarmonyLib;
 using MonkeyLoader.Resonite;
+using System.Runtime.CompilerServices;
 
 namespace ShowmanTools
 {
     [HarmonyPatch]
     [HarmonyPatchCategory(nameof(LinuxStreamingAudioFix))]
     internal sealed class LinuxStreamingAudioFix : ResoniteMonkey<LinuxStreamingAudioFix>
     {
+        private static readonly ConditionalWeakTable<InteractiveCamera, AudioListener> _secondaryListenersByCamera = [];
+        private static AudioListener? _secondaryUserspaceListener;
+
         public override bool CanBeDisabled => true;
 
+        [HarmonyPostfix]
+        [HarmonyPatch(typeof(InteractiveCamera), nameof(InteractiveCamera.OnCommonUpdate))]
+        private static void OnCommonUpdatePostfix(InteractiveCamera __instance)
+        {
+            if (!Enabled || __instance.Control is null || __instance.LocalUserRoot is null)
+                return;
+
+            _secondaryListenersByCamera.TryGetValue(__instance, out var secondaryListener);
+
+            if (secondaryListener is not null && (__instance.Control.IsDestroyed || __instance.Control.AudioFromCameraViewpoint || __instance.AudioSystem.StreamingOutput.Device is null))
+            {
+                secondaryListener.Slot.Destroy();
+                _secondaryListenersByCamera.Remove(__instance);
+
+                return;
+            }
+
+            if (__instance.Control.IsDestroyed || __instance.Control.AudioFromCameraViewpoint || __instance.AudioSystem.StreamingOutput.Device is null)
+                return;
+
+            if (secondaryListener is null)
+            {
+                var secondarySlot = __instance.LocalUserRoot.PrimaryListener.Target.Slot.Duplicate();
+                secondarySlot.Name = "Camera Listener";
+
+                secondaryListener = secondarySlot.GetComponent<AudioListener>();
+                secondaryListener.TargetOutput.Value = AudioListener.ListenerTarget.StreamingCamera;
+                secondaryListener.Enabled = true;
+
+                _secondaryListenersByCamera.Add(__instance, secondaryListener);
+            }
+        }
+
         [HarmonyPrefix]
         [HarmonyPatch(typeof(AudioSystem), nameof(AudioSystem.UpdateDefaultAudioOutput))]
         private static bool UpdateDefaultAudioOutputPrefix(AudioSystem __instance, Action<AudioOutputDriver>? ___DefaultAudioOutputChanged)
@@ -71,6 +108,7 @@ private static bool UpdateDefaultAudioOutputPrefix(AudioSystem __instance, Actio
             newDefault.RenderAudio = __instance.RenderAudio;
             newDefault.Start("Default Output");
 
+            // newStreaming will never be the same as newDefault
             if (newStreaming is not null)
             {
                 newStreaming.RenderAudio = __instance.RenderAudio;
@@ -80,6 +118,40 @@ private static bool UpdateDefaultAudioOutputPrefix(AudioSystem __instance, Actio
             __instance.PrimaryOutput.Device = newDefault;
             __instance.StreamingOutput.Device = newStreaming;
 
+            Userspace.Current.RunSynchronously(() =>
+            {
+                if (newStreaming is not null && _secondaryUserspaceListener is null)
+                {
+                    var secondarySlot = Userspace.Current.LocalUserRoot.PrimaryListener.Target.Slot.Parent.AddSlot("Camera Listener");
+
+                    _secondaryUserspaceListener = secondarySlot.AttachComponent<AudioListener>(false);
+                    _secondaryUserspaceListener.ActiveUser.Target = Userspace.Current.LocalUser;
+                    _secondaryUserspaceListener.TargetOutput.Value = AudioListener.ListenerTarget.StreamingCamera;
+                    _secondaryUserspaceListener.Enabled = true;
+
+                    // Add 'reverb' effect that mutes everything
+                    var reverb = secondarySlot.AttachComponent<AudioZitaReverb>(false);
+                    reverb.InDelay.Value = 0;
+                    reverb.Crossover.Value = 20;
+                    reverb.RT60Low.Value = .05f;
+                    reverb.RT60Mid.Value = .05f;
+                    reverb.HighFrequencyDamping.Value = 20000;
+                    reverb.EQ1Frequency.Value = 250;
+                    reverb.EQ1Level.Value = 0;
+                    reverb.EQ2Frequency.Value = 20000;
+                    reverb.EQ2Level.Value = 0;
+                    reverb.Mix.Value = 1;
+                    reverb.Level.Value = -90;
+
+                    _secondaryUserspaceListener.Effects.Add(reverb);
+                }
+                else
+                {
+                    _secondaryUserspaceListener?.Slot.Destroy();
+                    _secondaryUserspaceListener = null;
+                }
+            });
+
             ___DefaultAudioOutputChanged?.Invoke(newDefault);
             return false;
         }

ShowmanTools/ShowMustGoOn.cs

@@ -32,6 +32,9 @@ private static bool MuteCheck(Component audioStream)
                     .GetValue<ISyncRef>()
                     .Target;
 
+                if (stream is null)
+                    return false;
+
                 var isAudioStream = _audioStreams.TryGetValue(stream, out _);
 
                 return world.Focus == World.WorldFocus.Focused