public override void OnInspectorGUI()
    {
        DrawDefaultInspector();

        TransitionController myScript = (TransitionController)target;

        if (GUILayout.Button("Start Transition"))
        {
            myScript.StartTransition(() => Debug.Log("done"));
        }
    }
    public void ChangeScenesAsycBehindTransition(string newScene, Action callback)
    {
        string oldSceneName = SceneManager.GetActiveScene().name;

        AsyncOperation asyncLoad = SceneManager.LoadSceneAsync(newScene);

        asyncLoad.allowSceneActivation = false;
        _tController.StartTransition(() =>
        {
            callback();
            asyncLoad.allowSceneActivation = true;
        });
    }