Detect zoom level on ion-scroll


Hi, i’m trying to build a scale bar on a JPG map. I use ion-scroll to scroll and pinch-to-zoom.
I know my initial scale, but when I pinch-to-zoom I need to detect the current zoom level.

I understand Zynga is @ the heart of ion-scroll and does have a public API:
scrollerObj.getValues() => { left, top, zoom }

How can i implement this to ionic under $ionicScrollDelegate?

Kind regards,