for example:

```js
    if (delta.left) offset.left = offset.left + delta.left
    else            offset.top = offset.top + delta.top

    var arrowDelta              = delta.left * 2 - (delta.left ? width + actualWidth : height + actualHeight)
    var arrowPosition          = delta.left ? 'left' : 'top'
    var arrowOffsetPosition = delta.left ? 'offsetWidth' : 'offsetHeight'
```