From b1038628e7df2b828d4d127e596aa9ab05d893da Mon Sep 17 00:00:00 2001
From: Joonas Rikkonen <poe.regalis@gmail.com>
Date: Tue, 23 Apr 2019 11:22:04 +0300
Subject: [PATCH] (f314ad2a3) New music track when the end of the level is
 reached, decrease the volume of the background music layer 0 when there's
 multiple tracks playing at the same time

---
 .../Source/Sounds/SoundPlayer.cs              | 27 ++++++++++++++-----
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/Barotrauma/BarotraumaClient/Source/Sounds/SoundPlayer.cs b/Barotrauma/BarotraumaClient/Source/Sounds/SoundPlayer.cs
index 0a1abe7ea..9753a9f4b 100644
--- a/Barotrauma/BarotraumaClient/Source/Sounds/SoundPlayer.cs
+++ b/Barotrauma/BarotraumaClient/Source/Sounds/SoundPlayer.cs
@@ -35,6 +35,7 @@ namespace Barotrauma
     {
         public readonly string File;
         public readonly string Type;
+        public readonly bool DuckVolume;
 
         public readonly Vector2 IntensityRange;
                 
@@ -43,6 +44,7 @@ namespace Barotrauma
             this.File = Path.GetFullPath(element.GetAttributeString("file", ""));
             this.Type = element.GetAttributeString("type", "").ToLowerInvariant();
             this.IntensityRange = element.GetAttributeVector2("intensityrange", new Vector2(0.0f, 100.0f));
+            this.DuckVolume = element.GetAttributeBool("duckvolume", false);
         }
     }
 
@@ -277,6 +279,7 @@ namespace Barotrauma
                     movementSoundVolume = 0.0f;
                 }
             }
+        }
 
             if (waterAmbiences.Count > 1)
             {
@@ -515,7 +518,7 @@ namespace Barotrauma
                 //switch the music if nothing playing atm or the currently playing clip is not suitable anymore
                 else if (targetMusic[0] == null || currentMusic[0] == null || !suitableMusic.Any(m => m.File == currentMusic[0].Filename))
                 {
-                    targetMusic[0] = suitableMusic.GetRandom();                    
+                    targetMusic[0] = suitableMusic.GetRandom();
                 }
                                 
                 //get the appropriate intensity layers for current situation
@@ -550,6 +553,7 @@ namespace Barotrauma
                 updateMusicTimer = UpdateMusicInterval;
             }
 
+            int activeTrackCount = targetMusic.Count(m => m != null);
             for (int i = 0; i < MaxMusicChannels; i++)
             {
                 //nothing should be playing on this channel
@@ -589,7 +593,12 @@ namespace Barotrauma
                         musicChannel[i] = currentMusic[i].Play(0.0f, "music");
                         musicChannel[i].Looping = true;
                     }
-                    musicChannel[i].Gain = MathHelper.Lerp(musicChannel[i].Gain, 1.0f, MusicLerpSpeed * deltaTime);
+                    float targetGain = 1.0f;
+                    if (targetMusic[i].DuckVolume)
+                    {
+                        targetGain = (float)Math.Sqrt(1.0f / activeTrackCount);
+                    }
+                    musicChannel[i].Gain = MathHelper.Lerp(musicChannel[i].Gain, targetGain, MusicLerpSpeed * deltaTime);
                 }
             } 
         }
@@ -657,8 +666,7 @@ namespace Barotrauma
             foreach (Character character in Character.CharacterList)
             {
                 if (character.IsDead || !character.Enabled) continue;
-                EnemyAIController enemyAI = character.AIController as EnemyAIController;
-                if (enemyAI == null || (!enemyAI.AttackHumans && !enemyAI.AttackRooms)) continue;
+                if (!(character.AIController is EnemyAIController enemyAI) || (!enemyAI.AttackHumans && !enemyAI.AttackRooms)) continue;
 
                 if (targetSubmarine != null)
                 {
@@ -676,9 +684,16 @@ namespace Barotrauma
                 }
             }
 
-            if (GameMain.GameSession != null && Timing.TotalTime < GameMain.GameSession.RoundStartTime + 120.0)
+            if (GameMain.GameSession != null)
             {
-                return "start";
+                if (Submarine.Loaded != null && Level.Loaded != null && Submarine.MainSub.AtEndPosition)
+                {
+                    return "levelend";
+                }
+                if (Timing.TotalTime < GameMain.GameSession.RoundStartTime + 120.0)
+                {
+                    return "start";
+                }
             }
             
             return "default";