Miasma improvements (#9022)

Content.Client/Atmos/Miasma/FliesComponent.cs

@@ -0,0 +1,8 @@
+using Content.Shared.Atmos.Miasma;
+using Robust.Shared.GameStates;
+
+namespace Content.Client.Atmos.Miasma;
+
+[NetworkedComponent, RegisterComponent]
+public sealed class FliesComponent : SharedFliesComponent
+{ }

Content.Client/Atmos/Miasma/FliesSystem.cs

@@ -0,0 +1,41 @@
+using Robust.Client.GameObjects;
+using Robust.Shared.Utility;
+
+namespace Content.Client.Atmos.Miasma;
+
+public sealed class FliesSystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        SubscribeLocalEvent<FliesComponent, ComponentStartup>(FliesAdded);
+        SubscribeLocalEvent<FliesComponent, ComponentShutdown>(FliesRemoved);
+    }
+
+    private void FliesRemoved(EntityUid uid, FliesComponent component, ComponentShutdown args)
+    {
+        if (!TryComp<SpriteComponent>(uid, out var sprite))
+            return;
+
+        if (!sprite.LayerMapTryGet(FliesKey.Key, out var layer))
+            return;
+
+        sprite.RemoveLayer(layer);
+    }
+
+    private void FliesAdded(EntityUid uid, FliesComponent component, ComponentStartup args)
+    {
+        if (!TryComp<SpriteComponent>(uid, out var sprite))
+            return;
+
+        if (sprite.LayerMapTryGet(FliesKey.Key, out var _))
+            return;
+
+        var layer = sprite.AddLayer(new SpriteSpecifier.Rsi(new ResourcePath("Objects/Misc/flies.rsi"), "flies"));
+        sprite.LayerMapSet(FliesKey.Key, layer);
+    }
+
+    private enum FliesKey
+    {
+        Key,
+    }
+}