protected override void initialization()
        {
            base.initialization();

            previewSystem = new PreviewSystem();
            previewSystem.parentEditorWindow = this;

            reload();
        }
        protected override void OnDestroy()
        {
            if (previewSystem != null)
            {
                previewSystem.OnDestroy();
                previewSystem = null;
            }

            base.OnDestroy();
        }