Fix issues with scene loading, introduce an intermediate bootstrap scene

Assets/Scenes/BootstrapScene.unity

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Assets/Scenes/BootstrapScene.unity.meta

@@ -0,0 +1,7 @@
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Assets/Scripts/Core/SceneManagerService.cs

@@ -42,11 +42,29 @@ public class SceneManagerService : MonoBehaviour
 
     private readonly Dictionary<string, AsyncOperation> _activeLoads = new();
     private readonly Dictionary<string, AsyncOperation> _activeUnloads = new();
+    private const string BootstrapSceneName = "BootstrapScene";
 
     void Awake()
     {
         _instance = this;
         // DontDestroyOnLoad(gameObject);
+#if UNITY_EDITOR
+        // In Editor, set CurrentGameplayScene to the currently open scene at play start
+        if (Application.isPlaying)
+        {
+            var activeScene = SceneManager.GetActiveScene();
+            if (activeScene.IsValid())
+            {
+                CurrentGameplayScene = activeScene.name;
+            }
+        }
+#endif
+        // Ensure BootstrapScene is loaded at startup
+        var bootstrap = SceneManager.GetSceneByName(BootstrapSceneName);
+        if (!bootstrap.isLoaded)
+        {
+            SceneManager.LoadScene(BootstrapSceneName, LoadSceneMode.Additive);
+        }
     }
 
     void OnApplicationQuit()
@@ -196,7 +214,7 @@ public class SceneManagerService : MonoBehaviour
     }
 
     // Tracks the currently loaded gameplay scene (not persistent/bootstrapper)
-    public string CurrentGameplayScene { get; private set; } = "AppleHillsOverworld";
+    public string CurrentGameplayScene { get; private set; } = "MainMenu";
 
     // Switches from current gameplay scene to a new one
     public async Task SwitchSceneAsync(string newSceneName, IProgress<float> progress = null)
@@ -210,10 +228,8 @@ public class SceneManagerService : MonoBehaviour
             else
                 DestroyImmediate(astar.gameObject);
         }
-        // Load new scene
+        // Unload previous gameplay scene (if not BootstrapScene and not same as new)
-        await LoadSceneAsync(newSceneName, progress);
+        if (!string.IsNullOrEmpty(CurrentGameplayScene) && CurrentGameplayScene != newSceneName && CurrentGameplayScene != BootstrapSceneName)
-        // Unload previous scene (if not same)
-        if (!string.IsNullOrEmpty(CurrentGameplayScene) && CurrentGameplayScene != newSceneName)
         {
             var prevScene = SceneManager.GetSceneByName(CurrentGameplayScene);
             if (prevScene.isLoaded)
@@ -225,6 +241,14 @@ public class SceneManagerService : MonoBehaviour
                 Debug.LogWarning($"SceneManagerService: Previous scene '{CurrentGameplayScene}' is not loaded, skipping unload.");
             }
         }
+        // Ensure BootstrapScene is loaded before loading new scene
+        var bootstrap = SceneManager.GetSceneByName(BootstrapSceneName);
+        if (!bootstrap.isLoaded)
+        {
+            SceneManager.LoadScene(BootstrapSceneName, LoadSceneMode.Additive);
+        }
+        // Load new gameplay scene
+        await LoadSceneAsync(newSceneName, progress);
         // Update tracker
         CurrentGameplayScene = newSceneName;
     }

Assets/Scripts/UI/MainMenu.cs

@@ -1,12 +1,14 @@
+using System;
 using UnityEngine;
 using UnityEngine.SceneManagement;
 
 public class MainMenu : MonoBehaviour
 {
-    public void StartGame()
+    public async void StartGame()
     {
         // Replace with the actual scene name as set in Build Settings
-        SceneManager.LoadScene("AppleHillsOverworld");
+        var progress = new Progress<float>(p => Debug.Log($"Loading progress: {p * 100:F0}%"));
+        await SceneManagerService.Instance.SwitchSceneAsync("AppleHillsOverworld", progress);
     }
 
     public void QuitGame()

ProjectSettings/EditorBuildSettings.asset

@@ -20,6 +20,9 @@ EditorBuildSettings:
   - enabled: 1
     path: Assets/Scenes/MiniGames/DivingForPictures.unity
     guid: 0d57c89693f4e964b8b66e00e39ed1e7
+  - enabled: 1
+    path: Assets/Scenes/BootstrapScene.unity
+    guid: 706f6dec7a10d2542be1a3c21216158b
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