From 9d96e6d5e58c171b5adf19832a3f7519fa796be1 Mon Sep 17 00:00:00 2001
From: Adam Graham <adam@zigurous.com>
Date: Tue, 15 Jun 2021 16:54:21 -0500
Subject: [PATCH] Kill tweens on scene unload

---
 Runtime/TweenManager.cs | 28 +++++++++++++++++++++++-----
 Runtime/Tweening.cs     |  5 +++++
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/Runtime/TweenManager.cs b/Runtime/TweenManager.cs
index 7b63bf5..7251e99 100644
--- a/Runtime/TweenManager.cs
+++ b/Runtime/TweenManager.cs
@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using UnityEngine;
+using UnityEngine.SceneManagement;
 
 namespace Zigurous.Tweening
 {
@@ -39,8 +40,7 @@ internal static TweenManager Instance
                             GameObject singleton = new GameObject();
                             singleton.name = typeof(TweenManager).Name;
                             singleton.hideFlags = HideFlags.HideInHierarchy | HideFlags.HideInInspector;
-
-                            _instance = singleton.AddComponent<TweenManager>();
+                            singleton.AddComponent<TweenManager>();
                             DontDestroyOnLoad(singleton);
                         }
                     }
@@ -54,9 +54,14 @@ private void Awake()
         {
             _isUnloading = false;
 
-            if (_instance == null) {
+            if (_instance == null)
+            {
                 _instance = this;
-            } else {
+
+                SceneManager.sceneUnloaded += SceneUnloaded;
+            }
+            else
+            {
                 Destroy(this);
             }
         }
@@ -65,8 +70,11 @@ private void OnDestroy()
         {
             _isUnloading = true;
 
-            if (_instance == this) {
+            if (_instance == this)
+            {
                 _instance = null;
+
+                SceneManager.sceneUnloaded -= SceneUnloaded;
             }
 
             foreach (Tween tween in this.tweens) {
@@ -176,6 +184,16 @@ internal void Track(Tween tween)
             }
         }
 
+        /// <summary>
+        /// Kills all tweens when the active scene is unloaded.
+        /// </summary>
+        private void SceneUnloaded(Scene scene)
+        {
+            if (Tweening.killTweensOnSceneUnload) {
+                Tweening.KillAll();
+            }
+        }
+
     }
 
 }
diff --git a/Runtime/Tweening.cs b/Runtime/Tweening.cs
index cb9884e..3231a8c 100644
--- a/Runtime/Tweening.cs
+++ b/Runtime/Tweening.cs
@@ -43,6 +43,11 @@ public static class Tweening
         /// </summary>
         public static float overshoot = 1.70158f;
 
+        /// <summary>
+        /// Kills all tweens when the active scene is unloaded.
+        /// </summary>
+        public static bool killTweensOnSceneUnload = true;
+
         /// <summary>
         /// The initial amount of tweens that memory is allocated for when the
         /// system starts. Additional memory will be allocated as needed.