SoundSystem (#1604)

* Adds the SoundSystem static proxy class for the AudioSystem.
Added a shared IAudioSystem interface for the future.

* Moved ConnectedClient property from IPlayerSession down to ICommonSession.

* Connected up the SoundSystem to the client/server AudioSystems.

* Converted client calls over to the new system.

* Marked the old serverside functions to play sound obsolete, use the new ones from the IAudioSystem.

* Added ISharedPlayerManager to the IoC registration.

Robust.Client/Animations/AnimationTrackPlaySound.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using Robust.Client.GameObjects;
 using Robust.Shared.Audio;
 using Robust.Shared.GameObjects;
+using Robust.Shared.Player;
 
 namespace Robust.Client.Animations
 {
@@ -36,8 +37,7 @@ namespace Robust.Client.Animations
 
                 var keyFrame = KeyFrames[keyFrameIndex];
 
-                EntitySystem.Get<AudioSystem>()
-                    .Play(keyFrame.Resource, entity, keyFrame.AudioParamsFunc.Invoke());
+                SoundSystem.Play(Filter.Local(), keyFrame.Resource, entity, keyFrame.AudioParamsFunc.Invoke());
             }
 
             return (keyFrameIndex, playingTime);

Robust.Client/ClientIoC.cs

@@ -24,6 +24,7 @@ using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Network;
+using Robust.Shared.Players;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Reflection;
 
@@ -53,6 +54,7 @@ namespace Robust.Client
             IoCManager.Register<IClientGameStateManager, ClientGameStateManager>();
             IoCManager.Register<IBaseClient, BaseClient>();
             IoCManager.Register<IPlayerManager, PlayerManager>();
+            IoCManager.Register<ISharedPlayerManager, PlayerManager>();
             IoCManager.Register<IStateManager, StateManager>();
             IoCManager.Register<IUserInterfaceManager, UserInterfaceManager>();
             IoCManager.Register<IUserInterfaceManagerInternal, UserInterfaceManager>();

Robust.Client/GameObjects/EntitySystems/AudioSystem.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using JetBrains.Annotations;
 using Robust.Client.Audio;
@@ -11,12 +10,13 @@ using Robust.Shared.Log;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
 using Robust.Shared.Physics;
+using Robust.Shared.Player;
 using Robust.Shared.Utility;
 
 namespace Robust.Client.GameObjects
 {
     [UsedImplicitly]
-    public class AudioSystem : EntitySystem
+    public class AudioSystem : EntitySystem, IAudioSystem
     {
         [Dependency] private readonly IResourceCache _resourceCache = default!;
         [Dependency] private readonly IMapManager _mapManager = default!;
@@ -25,9 +25,7 @@ namespace Robust.Client.GameObjects
         [Dependency] private readonly IEntityManager _entityManager = default!;
 
         private readonly List<PlayingStream> _playingClydeStreams = new();
-
-        public int OcclusionCollisionMask;
-
+        
         /// <inheritdoc />
         public override void Initialize()
         {
@@ -35,6 +33,8 @@ namespace Robust.Client.GameObjects
             SubscribeNetworkEvent<PlayAudioGlobalMessage>(PlayAudioGlobalHandler);
             SubscribeNetworkEvent<PlayAudioPositionalMessage>(PlayAudioPositionalHandler);
             SubscribeNetworkEvent<StopAudioMessageClient>(StopAudioMessageHandler);
+
+            SubscribeLocalEvent<SoundSystem.QueryAudioSystem>((ev => ev.Audio = this));
         }
 
         private void StopAudioMessageHandler(StopAudioMessageClient ev)
@@ -176,7 +176,6 @@ namespace Robust.Client.GameObjects
         {
             stream.Source.Dispose();
             stream.Done = true;
-            stream.DoPlaybackDone();
         }
 
         /// <summary>
@@ -335,92 +334,30 @@ namespace Robust.Client.GameObjects
             {
                 Source.StopPlaying();
             }
-
-            public event Action? PlaybackDone;
-
-            public void DoPlaybackDone()
-            {
-                PlaybackDone?.Invoke();
-            }
-        }
-    }
-
-    public interface IPlayingAudioStream
-    {
-        void Stop();
-
-        event Action PlaybackDone;
-    }
-
-    public static class AudioSystemExtensions
-    {
-
-        /// <summary>
-        ///     Play an audio file following an entity.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="entity">The entity "emitting" the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static IPlayingAudioStream? Play(
-            this IEntity entity,
-            string filename,
-            AudioParams? audioParams,
-            AudioSystem? audioSystem = null)
-        {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            return audioSystem.Play(filename, entity, audioParams);
         }
 
-        /// <summary>
-        ///     Play an audio stream following an entity.
-        /// </summary>
-        /// <param name="stream">The audio stream to play.</param>
-        /// <param name="entity">The entity "emitting" the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static IPlayingAudioStream? Play(
-            this IEntity entity,
-            AudioStream stream,
-            AudioParams? audioParams = null,
-            AudioSystem? audioSystem = null)
+        /// <inheritdoc />
+        public int DefaultSoundRange => 25;
+
+        /// <inheritdoc />
+        public int OcclusionCollisionMask { get; set; }
+
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, AudioParams? audioParams = null)
         {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            return audioSystem.Play(stream, entity, audioParams);
+            return Play(filename, audioParams);
         }
 
-        /// <summary>
-        ///     Play an audio file at a static position.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="coordinates">The coordinates at which to play the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static IPlayingAudioStream? Play(
-            this EntityCoordinates coordinates,
-            string filename,
-            AudioParams? audioParams = null,
-            AudioSystem? audioSystem = null)
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, IEntity entity, AudioParams? audioParams = null)
         {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            return audioSystem.Play(filename, coordinates, audioParams);
+            return Play(filename, entity, audioParams);
         }
 
-        /// <summary>
-        ///     Play an audio stream at a static position.
-        /// </summary>
-        /// <param name="stream">The audio stream to play.</param>
-        /// <param name="coordinates">The coordinates at which to play the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static IPlayingAudioStream? Play(
-            this EntityCoordinates coordinates,
-            AudioStream stream,
-            AudioParams? audioParams = null,
-            AudioSystem? audioSystem = null)
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, EntityCoordinates coordinates, AudioParams? audioParams = null)
         {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            return audioSystem.Play(stream, coordinates, audioParams);
+            return Play(filename, coordinates, audioParams);
         }
     }
 }

Robust.Client/Player/PlayerManager.cs

@@ -207,7 +207,7 @@ namespace Robust.Client.Player
                     if (state.UserId == LocalPlayer!.UserId)
                     {
                         LocalPlayer.InternalSession = newSession;
-
+                        newSession.ConnectedClient = _network.ServerChannel!;
                         // We just connected to the server, hurray!
                         LocalPlayer.SwitchState(SessionStatus.Connecting, newSession.Status);
                     }

Robust.Client/Player/PlayerSession.cs

@@ -39,6 +39,9 @@ namespace Robust.Client.Player
         /// <inheritdoc />
         internal short Ping { get; set; }
 
+        /// <inheritdoc />
+        public INetChannel ConnectedClient { get; internal set; } = null!;
+
         /// <inheritdoc />
         short ICommonSession.Ping
         {

Robust.Server/GameObjects/EntitySystems/AudioSystem.cs

@@ -1,29 +1,31 @@
-using System;
+using System;
 using System.Collections.Generic;
+using System.Linq;
 using Robust.Server.Player;
 using Robust.Shared.Audio;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
-using static Robust.Server.GameObjects.AudioSystem;
+using Robust.Shared.Player;
+using Robust.Shared.Players;
 
 namespace Robust.Server.GameObjects
 {
-    public class AudioSystem : EntitySystem
+    public class AudioSystem : EntitySystem, IAudioSystem
     {
         [Dependency] private readonly IPlayerManager _playerManager = default!;
 
-        public const int AudioDistanceRange = 25;
+        private const int AudioDistanceRange = 25;
 
         private uint _streamIndex;
 
-        public class AudioSourceServer
+        private class AudioSourceServer : IPlayingAudioStream
         {
             private readonly uint _id;
             private readonly AudioSystem _audioSystem;
-            private readonly IEnumerable<IPlayerSession>? _sessions;
+            private readonly IEnumerable<ICommonSession>? _sessions;
 
-            internal AudioSourceServer(AudioSystem parent, uint identifier, IEnumerable<IPlayerSession>? sessions = null)
+            internal AudioSourceServer(AudioSystem parent, uint identifier, IEnumerable<ICommonSession>? sessions = null)
             {
                 _audioSystem = parent;
                 _id = identifier;
@@ -35,7 +37,13 @@ namespace Robust.Server.GameObjects
             }
         }
 
-        private void InternalStop(uint id, IEnumerable<IPlayerSession>? sessions = null)
+        /// <inheritdoc />
+        public override void Initialize()
+        {
+            SubscribeLocalEvent<SoundSystem.QueryAudioSystem>((ev => ev.Audio = this));
+        }
+
+        private void InternalStop(uint id, IEnumerable<ICommonSession>? sessions = null)
         {
             var msg = new StopAudioMessageClient
             {
@@ -65,7 +73,9 @@ namespace Robust.Server.GameObjects
         /// <param name="audioParams"></param>
         /// <param name="predicate">The predicate that will be used to send the audio to players, or null to send to everyone.</param>
         /// <param name="excludedSession">Session that won't receive the audio message.</param>
-        public AudioSourceServer PlayGlobal(string filename, AudioParams? audioParams = null, Func<IPlayerSession, bool>? predicate = null, IPlayerSession? excludedSession = null)
+        /// <param name="recipients"></param>
+        [Obsolete("Use the Play() overload.")]
+        public IPlayingAudioStream PlayGlobal(string filename, AudioParams? audioParams = null, Func<IPlayerSession, bool>? predicate = null, IPlayerSession? excludedSession = null)
         {
             var id = CacheIdentifier();
             var msg = new PlayAudioGlobalMessage
@@ -81,7 +91,7 @@ namespace Robust.Server.GameObjects
                 return new AudioSourceServer(this, id);
             }
 
-            var players = predicate != null ? _playerManager.GetPlayersBy(predicate) : _playerManager.GetAllPlayers();
+            IList<IPlayerSession> players = predicate != null ? _playerManager.GetPlayersBy(predicate) : _playerManager.GetAllPlayers();
 
             for (var i = players.Count - 1; i >= 0; i--)
             {
@@ -96,7 +106,6 @@ namespace Robust.Server.GameObjects
             }
 
             return new AudioSourceServer(this, id, players);
-
         }
 
         /// <summary>
@@ -107,7 +116,8 @@ namespace Robust.Server.GameObjects
         /// <param name="audioParams"></param>
         /// <param name="range">The max range at which the audio will be heard. Less than or equal to 0 to send to every player.</param>
         /// <param name="excludedSession">Sessions that won't receive the audio message.</param>
-        public AudioSourceServer PlayFromEntity(string filename, IEntity entity, AudioParams? audioParams = null, int range = AudioDistanceRange, IPlayerSession? excludedSession = null)
+        [Obsolete("Use the Play() overload.")]
+        public IPlayingAudioStream PlayFromEntity(string filename, IEntity entity, AudioParams? audioParams = null, int range = AudioDistanceRange, IPlayerSession? excludedSession = null)
         {
             var id = CacheIdentifier();
 
@@ -120,13 +130,19 @@ namespace Robust.Server.GameObjects
                 Identifier = id,
             };
 
+            // send to every player
             if (range <= 0 && excludedSession == null)
             {
                 RaiseNetworkEvent(msg);
                 return new AudioSourceServer(this, id);
             }
 
-            var players = range > 0.0f ? _playerManager.GetPlayersInRange(entity.Transform.Coordinates, range) : _playerManager.GetAllPlayers();
+            List<IPlayerSession> players;
+
+            if (range > 0.0f)
+                players = _playerManager.GetPlayersInRange(entity.Transform.Coordinates, range);
+            else
+                players = _playerManager.GetAllPlayers();
 
             for (var i = players.Count - 1; i >= 0; i--)
             {
@@ -151,7 +167,8 @@ namespace Robust.Server.GameObjects
         /// <param name="audioParams"></param>
         /// <param name="range">The max range at which the audio will be heard. Less than or equal to 0 to send to every player.</param>
         /// <param name="excludedSession">Session that won't receive the audio message.</param>
-        public AudioSourceServer PlayAtCoords(string filename, EntityCoordinates coordinates, AudioParams? audioParams = null, int range = AudioDistanceRange, IPlayerSession? excludedSession = null)
+        [Obsolete("Use the Play() overload.")]
+        public IPlayingAudioStream PlayAtCoords(string filename, EntityCoordinates coordinates, AudioParams? audioParams = null, int range = AudioDistanceRange, IPlayerSession? excludedSession = null)
         {
             var id = CacheIdentifier();
             var msg = new PlayAudioPositionalMessage
@@ -168,7 +185,12 @@ namespace Robust.Server.GameObjects
                 return new AudioSourceServer(this, id);
             }
 
-            var players = range > 0.0f ? _playerManager.GetPlayersInRange(coordinates, range) : _playerManager.GetAllPlayers();
+            List<IPlayerSession> players;
+
+            if (range > 0.0f)
+                players = _playerManager.GetPlayersInRange(coordinates, range);
+            else
+                players = _playerManager.GetAllPlayers();
 
             for (var i = players.Count - 1; i >= 0; i--)
             {
@@ -185,88 +207,102 @@ namespace Robust.Server.GameObjects
             return new AudioSourceServer(this, id, players);
         }
 
-        #region DEPRECATED
-        /// <summary>
-        ///     Play an audio file globally, without position.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="audioParams"></param>
-        [Obsolete("Deprecated. Use PlayGlobal instead.")]
-        public void Play(string filename, AudioParams? audioParams = null)
+        /// <inheritdoc />
+        public int DefaultSoundRange => AudioDistanceRange;
+
+        /// <inheritdoc />
+        public int OcclusionCollisionMask { get; set; }
+
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, AudioParams? audioParams = null)
         {
-            PlayGlobal(filename, audioParams);
+            var id = CacheIdentifier();
+            var msg = new PlayAudioGlobalMessage
+            {
+                FileName = filename,
+                AudioParams = audioParams ?? AudioParams.Default,
+                Identifier = id
+            };
+
+            var players = (playerFilter as IFilter).Recipients;
+            foreach (var player in players)
+            {
+                RaiseNetworkEvent(msg, player.ConnectedClient);
+            }
+
+            return new AudioSourceServer(this, id, players);
         }
 
-
-        /// <summary>
-        ///     Play an audio file following an entity.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="entity">The entity "emitting" the audio.</param>
-        /// <param name="audioParams"></param>
-        [Obsolete("Deprecated. Use PlayFromEntity instead.")]
-        public void Play(string filename, IEntity entity, AudioParams? audioParams = null)
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, IEntity entity, AudioParams? audioParams = null)
         {
-            PlayFromEntity(filename, entity, audioParams);
+            //TODO: Calculate this from PAS
+            var range = audioParams is null || audioParams.Value.MaxDistance <= 0 ? AudioDistanceRange : audioParams.Value.MaxDistance;
+
+            var id = CacheIdentifier();
+
+            var msg = new PlayAudioEntityMessage
+            {
+                FileName = filename,
+                Coordinates = entity.Transform.Coordinates,
+                EntityUid = entity.Uid,
+                AudioParams = audioParams ?? AudioParams.Default,
+                Identifier = id,
+            };
+            
+            IList<ICommonSession> players;
+            var recipients = (playerFilter as IFilter).Recipients;
+
+            if (range > 0.0f)
+                players = PASInRange(recipients, entity.Transform.MapPosition, range);
+            else
+                players = recipients;
+
+            foreach (var player in players)
+            {
+                RaiseNetworkEvent(msg, player.ConnectedClient);
+            }
+            
+            return new AudioSourceServer(this, id, players);
         }
 
-        /// <summary>
-        ///     Play an audio file at a static position.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="coordinates">The coordinates at which to play the audio.</param>
-        /// <param name="audioParams"></param>
-        [Obsolete("Deprecated. Use PlayAtCoords instead.")]
-        public void Play(string filename, EntityCoordinates coordinates, AudioParams? audioParams = null)
+        /// <inheritdoc />
+        public IPlayingAudioStream? Play(Filter playerFilter, string filename, EntityCoordinates coordinates, AudioParams? audioParams = null)
         {
-            PlayAtCoords(filename, coordinates, audioParams);
+            //TODO: Calculate this from PAS
+            var range = audioParams is null || audioParams.Value.MaxDistance <= 0 ? AudioDistanceRange : audioParams.Value.MaxDistance;
+
+            var id = CacheIdentifier();
+            var msg = new PlayAudioPositionalMessage
+            {
+                FileName = filename,
+                Coordinates = coordinates,
+                AudioParams = audioParams ?? AudioParams.Default,
+                Identifier = id
+            };
+            
+            IList<ICommonSession> players;
+            var recipients = (playerFilter as IFilter).Recipients;
+
+            if (range > 0.0f)
+                players = PASInRange(recipients, coordinates.ToMap(EntityManager), range);
+            else
+                players = recipients;
+
+            foreach (var player in players)
+            {
+                RaiseNetworkEvent(msg, player.ConnectedClient);
+            }
+            
+            return new AudioSourceServer(this, id, players);
         }
 
-        #endregion
-    }
-
-    public static class AudioSystemExtensions
-    {
-        /// <summary>
-        ///     Play an audio file following an entity.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="entity">The entity "emitting" the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="range">The max range at which the audio will be heard. Less than or equal to 0 to send to every player.</param>
-        /// <param name="excludedSession">Sessions that won't receive the audio message.</param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static void PlaySoundFrom(
-            this IEntity entity,
-            string filename,
-            AudioParams? audioParams = null,
-            int range = AudioDistanceRange,
-            IPlayerSession? excludedSession = null,
-            AudioSystem? audioSystem = null)
+        private static List<ICommonSession> PASInRange(IEnumerable<ICommonSession> players, MapCoordinates position, float range)
         {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            audioSystem.PlayFromEntity(filename, entity, audioParams, range, excludedSession);
-        }
-
-        /// <summary>
-        ///     Play an audio file at a static position.
-        /// </summary>
-        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
-        /// <param name="coordinates">The coordinates at which to play the audio.</param>
-        /// <param name="audioParams"></param>
-        /// <param name="range">The max range at which the audio will be heard. Less than or equal to 0 to send to every player.</param>
-        /// <param name="excludedSession">Session that won't receive the audio message.</param>
-        /// <param name="audioSystem">A pre-fetched instance of <see cref="AudioSystem"/> to use, can be null.</param>
-        public static void PlaySoundFrom(
-            this EntityCoordinates coordinates,
-            string filename,
-            AudioParams? audioParams = null,
-            int range = AudioDistanceRange,
-            IPlayerSession? excludedSession = null,
-            AudioSystem? audioSystem = null)
-        {
-            audioSystem ??= EntitySystem.Get<AudioSystem>();
-            audioSystem.PlayAtCoords(filename, coordinates, audioParams, range, excludedSession);
+            return players.Where(x =>
+                    x.AttachedEntity != null &&
+                    position.InRange(x.AttachedEntity.Transform.MapPosition, range))
+                .ToList();
         }
     }
 }

Robust.Server/Player/IPlayerSession.cs

@@ -7,7 +7,6 @@ namespace Robust.Server.Player
 {
     public interface IPlayerSession : ICommonSession
     {
-        INetChannel ConnectedClient { get; }
         DateTime ConnectedTime { get; }
 
         /// <summary>

Robust.Server/ServerIoC.cs

@@ -18,6 +18,7 @@ using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Network;
+using Robust.Shared.Players;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Reflection;
 using Robust.Shared.Timing;
@@ -45,6 +46,7 @@ namespace Robust.Server
             IoCManager.Register<IMapLoader, MapLoader>();
             IoCManager.Register<IPlacementManager, PlacementManager>();
             IoCManager.Register<IPlayerManager, PlayerManager>();
+            IoCManager.Register<ISharedPlayerManager, PlayerManager>();
             IoCManager.Register<IPrototypeManager, ServerPrototypeManager>();
             IoCManager.Register<IReflectionManager, ServerReflectionManager>();
             IoCManager.Register<IResourceManager, ResourceManager>();

Robust.Shared/Audio/IAudioSystem.cs

@@ -0,0 +1,48 @@
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.Shared.Player;
+
+namespace Robust.Shared.Audio
+{
+    /// <summary>
+    /// Common interface for the Audio System, which is used to play sounds on clients.
+    /// </summary>
+    public interface IAudioSystem
+    {
+        /// <summary>
+        /// Default max range at which the sound can be heard.
+        /// </summary>
+        int DefaultSoundRange { get; }
+
+        /// <summary>
+        /// Used in the PAS to designate the physics collision mask of occluders.
+        /// </summary>
+        int OcclusionCollisionMask { get; set; }
+
+        /// <summary>
+        /// Play an audio file globally, without position.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        IPlayingAudioStream? Play(Filter playerFilter, string filename, AudioParams? audioParams = null);
+
+        /// <summary>
+        /// Play an audio file following an entity.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="entity">The entity "emitting" the audio.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        IPlayingAudioStream? Play(Filter playerFilter, string filename, IEntity entity, AudioParams? audioParams = null);
+
+        /// <summary>
+        /// Play an audio file at a static position.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="coordinates">The coordinates at which to play the audio.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        IPlayingAudioStream? Play(Filter playerFilter, string filename, EntityCoordinates coordinates, AudioParams? audioParams = null);
+    }
+}

Robust.Shared/Audio/IPlayingAudioStream.cs

@@ -0,0 +1,7 @@
+namespace Robust.Shared.Audio
+{
+    public interface IPlayingAudioStream
+    {
+        void Stop();
+    }
+}

Robust.Shared/Audio/SoundSystem.cs

@@ -0,0 +1,82 @@
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Map;
+using Robust.Shared.Player;
+
+namespace Robust.Shared.Audio
+{
+    /// <summary>
+    /// A static proxy class for interfacing with the AudioSystem.
+    /// </summary>
+    public static class SoundSystem
+    {
+        /// <summary>
+        /// Default max range at which the sound can be heard.
+        /// </summary>
+        public static int DefaultSoundRange => GetAudio()?.DefaultSoundRange ?? 0;
+
+        /// <summary>
+        /// Used in the PAS to designate the physics collision mask of occluders.
+        /// </summary>
+        public static int OcclusionCollisionMask
+        {
+            get => GetAudio()?.OcclusionCollisionMask ?? 0;
+            set
+            {
+                var audio = GetAudio();
+
+                if (audio is null)
+                    return;
+                audio.OcclusionCollisionMask = value;
+            }
+        }
+
+        private static IAudioSystem? GetAudio()
+        {
+            // There appears to be no way to get a System by interface.
+            var args = new QueryAudioSystem();
+            IoCManager.Resolve<IEntityManager>().EventBus.RaiseEvent(EventSource.Local, args);
+            return args.Audio;
+        }
+
+        /// <summary>
+        /// Play an audio file globally, without position.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        public static IPlayingAudioStream? Play(Filter playerFilter, string filename, AudioParams? audioParams = null)
+        {
+            return GetAudio()?.Play(playerFilter, filename, audioParams);
+        }
+
+        /// <summary>
+        /// Play an audio file following an entity.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="entity">The entity "emitting" the audio.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        public static IPlayingAudioStream? Play(Filter playerFilter, string filename, IEntity entity, AudioParams? audioParams = null)
+        {
+            return GetAudio()?.Play(playerFilter, filename, entity, audioParams);
+        }
+
+        /// <summary>
+        /// Play an audio file at a static position.
+        /// </summary>
+        /// <param name="playerFilter">The set of players that will hear the sound.</param>
+        /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
+        /// <param name="coordinates">The coordinates at which to play the audio.</param>
+        /// <param name="audioParams">Audio parameters to apply when playing the sound.</param>
+        public static IPlayingAudioStream? Play(Filter playerFilter, string filename, EntityCoordinates coordinates, AudioParams? audioParams = null)
+        {
+            return GetAudio()?.Play(playerFilter, filename, coordinates, audioParams);
+        }
+
+        internal class QueryAudioSystem : EntitySystemMessage
+        {
+            public IAudioSystem? Audio { get; set; }
+        }
+    }
+}

Robust.Shared/Players/ICommonSession.cs

@@ -38,5 +38,14 @@ namespace Robust.Shared.Players
         /// Current connection latency of this session from the server to their client.
         /// </summary>
         short Ping { get; internal set; }
+
+        /// <summary>
+        /// The current network channel for this player.
+        /// </summary>
+        /// <remarks>
+        /// On the Server every player has a network channel,
+        /// on the Client only the LocalPlayer has a network channel.
+        /// </remarks>
+        INetChannel ConnectedClient { get; }
     }
 }