Scroll Fire     

“Scroll Fire” is a feature that enables a method to be called (once and only once) when user scrolls current page to a specific scroll position in pixels.

For ease of use, its implementation is through a Vue Directive called v-scroll-fire.

NOTE
There is also a v-scroll directive which fires whenever user scrolls the page, available to read here.

<!-- Template for VueModel below -->
....
<div v-scroll-fire="bounceImage">...</div>
....

// VueModel for template above
{
  ...,
  methods: {
    bounceImage (element) {
      Velocity(element, 'callout.tada', {
        display: null
      })
    }
  }
}

IMPORTANT
For performance purposes, the scroll listener function injected is by default debounced by 50ms. Read more about debouncing here.