I have a list of events with start and end date given, now I want to drag them into one resource.
To limit event moving only in vertical direction, I did the following changes.
```
dp.onEventMoving = (args) ->
args.start = args.e.start()
args.end = args.e.end()
if args.external
dp.scrollTo(args.e.start(), false, 'middle')
```
it works, the drop placeholder only appears at given date period, but the overlapping highlight does not work as expected, how can I recalculate args with the updated start and end (says args.e.start and args.e.end).