Add pitch variations (#874)

Content.Server/GameObjects/Components/Sound/EmitSoundOnUseComponent.cs

@@ -1,4 +1,5 @@
 using Content.Server.GameObjects.EntitySystems;
+using Content.Shared.Audio;
 using Robust.Shared.Audio;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization;
@@ -16,17 +17,24 @@ namespace Content.Server.GameObjects.Components.Sound
         public override string Name => "EmitSoundOnUse";
 
         public string _soundName;
+        public float _pitchVariation;
 
         public override void ExposeData(ObjectSerializer serializer)
         {
             base.ExposeData(serializer);
-            serializer.DataField(ref _soundName, "sound", "");
+            serializer.DataField(ref _soundName, "sound", string.Empty);
+            serializer.DataField(ref _pitchVariation, "variation", 0.0f);
         }
 
         bool IUse.UseEntity(UseEntityEventArgs eventArgs)
         {
             if (!string.IsNullOrWhiteSpace(_soundName))
             {
+                if (_pitchVariation > 0.0)
+                {
+                    Owner.GetComponent<SoundComponent>().Play(_soundName, AudioHelpers.WithVariation(_pitchVariation).WithVolume(-2f));
+                    return true;
+                }
                 Owner.GetComponent<SoundComponent>().Play(_soundName, AudioParams.Default.WithVolume(-2f));
                 return true;
             }

Content.Shared/Audio/AudioHelpers.cs

@@ -0,0 +1,22 @@
+using System;
+using Content.Shared.GameObjects.Components.Sound;
+using Robust.Shared.Audio;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Interfaces.Random;
+using Robust.Shared.IoC;
+using Robust.Shared.Log;
+using Robust.Shared.Random;
+
+namespace Content.Shared.Audio
+{
+    public static class AudioHelpers{
+        /// <summary>
+        ///     Returns a random pitch.
+        /// </summary>
+        public static AudioParams WithVariation(float amplitude)
+        {
+            var scale = (float)(IoCManager.Resolve<IRobustRandom>().NextGaussian(1, amplitude));
+            return AudioParams.Default.WithPitchScale(scale);
+        }
+    }
+}

Resources/Prototypes/Entities/Items/bike_horn.yml

@@ -20,6 +20,7 @@
   - type: Sound
   - type: EmitSoundOnUse
     sound: /Audio/items/bikehorn.ogg
+    variation: 0.2
 
   - type: UseDelay
     delay: 0.5