Fix scene transitions and add demoable transition between two scenes

Assets/Scripts/CharacterManager.cs

@@ -0,0 +1,56 @@
+using System.Collections;
+using UnityEngine;
+using UnityEngine.SceneManagement;
+
+namespace Scampz.GameJam
+{
+  public class CharacterManager : MonoBehaviour
+  {
+    public static CharacterManager Instance;
+    private bool gameStart;
+
+    void Awake()
+    {
+      if (!gameStart)
+      {
+        Instance = this;
+        LoadScene(0, LoadSceneMode.Additive);
+        gameStart = true;
+      }
+    }
+
+    public void LoadScene(int levelIndex, LoadSceneMode loadSceneMode)
+    {
+      StartCoroutine(LoadSceneAsync(levelIndex, loadSceneMode));
+    }
+
+    public void UnloadScene(int levelIndex)
+    {
+      StartCoroutine(UnloadSceneAsync(levelIndex));
+    }
+
+    IEnumerator LoadSceneAsync(int levelIndex, LoadSceneMode loadSceneMode)
+    {
+      yield return null;
+
+      var loadSceneOperation = SceneManager.LoadSceneAsync(levelIndex, loadSceneMode);
+      loadSceneOperation.allowSceneActivation = false;
+      while (!loadSceneOperation.isDone)
+      {
+        if (loadSceneOperation.progress >= 0.9f)
+          break;
+      }
+
+      loadSceneOperation.allowSceneActivation = true;
+      yield return loadSceneOperation;
+    }
+
+    IEnumerator UnloadSceneAsync(int levelIndex)
+    {
+      yield return null;
+
+      SceneManager.UnloadSceneAsync(levelIndex);
+    }
+
+  }
+}

Assets/Scripts/LevelChanger.cs

@@ -1,4 +1,3 @@
-using System.Collections;
 using UnityEngine;
 using UnityEngine.SceneManagement;
 
@@ -14,12 +13,12 @@ namespace Scampz.GameJam
     public void OnTriggerEnter(Collider collider)
     {
       animator.SetTrigger("FadeOut");
-      StartCoroutine(LoadScene(sceneIndex));
+      CharacterManager.Instance.LoadScene(sceneIndex, LoadSceneMode.Additive);
     }
 
     public void OnFadeComplete()
     {
-      StartCoroutine(LoadScene(sceneIndex));
+      CharacterManager.Instance.LoadScene(sceneIndex, LoadSceneMode.Additive);
     }
 
     private void Awake()
@@ -29,27 +28,5 @@ namespace Scampz.GameJam
       else
         Singleton = this;
     }
-
-    private void FadeToLevel()
-    {
-      animator.SetTrigger("FadeOut");
-    }
-
-    private IEnumerator LoadScene(int levelIndex)
-    {
-
-      yield return null;
-
-      var loadSceneOperation = SceneManager.LoadSceneAsync(levelIndex);
-      loadSceneOperation.allowSceneActivation = false;
-      while (!loadSceneOperation.isDone)
-      {
-        if (loadSceneOperation.progress >= 0.9f)
-          break;
-      }
-
-      loadSceneOperation.allowSceneActivation = true;
-      yield return loadSceneOperation;
-    }
   }
 }

Assets/Scripts/LoadScene.cs

@@ -0,0 +1,21 @@
+using UnityEngine;
+using UnityEngine.SceneManagement;
+
+namespace Scampz.GameJam
+{
+  public class LoadScene : MonoBehaviour
+  {
+    private bool loaded = false;
+    public int sceneIndex;
+
+    void OnTriggerEnter(Collider collider)
+    {
+      if (!loaded)
+      {
+        loaded = true;
+
+        CharacterManager.Instance.LoadScene(sceneIndex, LoadSceneMode.Additive);
+      }
+    }
+  }
+}

Assets/Scripts/UnloadScene.cs

@@ -0,0 +1,20 @@
+using UnityEngine;
+
+namespace Scampz.GameJam
+{
+  public class UnloadScene : MonoBehaviour
+  {
+    public int scene;
+    private bool unloaded = false;
+
+    void OnTriggerEnter(Collider collider)
+    {
+      if (!unloaded)
+      {
+        unloaded = true;
+
+        CharacterManager.Instance.UnloadScene(scene);
+      }
+    }
+  }
+}