void OnPlayModeStateChanged(PlayModeStateChange p)
 {
     if (EditorApplication.isPlaying)
     {
         window = EditorUtility.InstanceIDToObject(windowID) as NL_ObjectPlacementTool_window;
         Repaint();
     }
 }
 void OnFocus()
 {
     if (!EditorApplication.isPlaying)
     {
         window = EditorUtility.InstanceIDToObject(windowID) as NL_ObjectPlacementTool_window;
         Repaint();
     }
 }
    public static void OPTWindow()
    {
        window = GetWindow <NL_ObjectPlacementTool_window> ();

        GUIContent titleIcon = new GUIContent(" OPT", (Texture2D)AssetDatabase.LoadAssetAtPath(OPTFolder + "WindowIcon.png", typeof(Texture2D)));

        window.titleContent = titleIcon;

        window.windowID = window.GetInstanceID();

        window.maxSize = new Vector2(480, 2000);
        window.minSize = new Vector2(400, 330);
    }