cross-browser-page-measures.js

/**
 * scroll distance
 * pixel distance to bottom of viewport
 */
function depth(){
  return (window.pageYOffset || document.body.scrollTop || document.documentElement.scrollTop || 0) +
    (window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight)
}

/**
 * height of the page in pixels
 */
function pageHeight(){
  return Math.max(
    document.body.scrollHeight,
    document.documentElement.scrollHeight,
    document.body.offsetHeight,
    document.documentElement.offsetHeight,
    document.body.clientHeight,
    document.documentElement.clientHeight
  )
}