title: How to know the difference between a zoom event originating from clicking the the zoom nav control vs a fitBounds zoom
body: <p>Using mapbox-gl-js 0.47.0</p>
  
  <p>I am listening to <a href="https://www.mapbox.com/mapbox-gl-js/api/#mapboxzoomevent" rel="nofollow noreferrer">mapbox zoom end event</a></p>
  
  <p>Is there a way to know if the the ^ zoom end event originated from clicking the maps zoom control, or from the <a href="https://www.mapbox.com/mapbox-gl-js/api/#map#fitbounds" rel="nofollow noreferrer">fitBounds</a> method being called?</p>
  
  <p>I know there is a way to pass additional event data to the fitBounds method that I could key from to know. </p>
  
  <p>But what if I did not control the implementation?</p>
  
  <p>Hope this makes sense.</p>