elVis

element visibility / inview / impression

Default:

elVis('classname', callbackFunction);

With options:

elVis(query, callback, {
  time: 1000,         // INT: minimum milliseconds on screen, defaults to 500
  part: 100           // INT: minimum percentage of element visible, defaults to 50
  selector: 'attr',   // STRING: class|id|attr|tag, defaults to class
  find: 'src'         // STRING: looks at selector children and returns the first match
}};

Callback object:

{
  "item": "1/3",
  "time": "2017-02-28T09:47:55.575Z",
  "top": "1135/4422",
  "props": {
    "class": "elvis one",
    "id": "firstelement",
    "some-attribute": "some data",
    "src": "image.png"
  }
}