# http://paulirish.com/2011/requestanimationframe-for-smart-animating/
# http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

# requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel

# MIT license
(->
  lastTime = 0
  vendors = [
    "ms"
    "moz"
    "webkit"
    "o"
  ]
  x = 0

  while x < vendors.length and not window.requestAnimationFrame
    window.requestAnimationFrame = window[vendors[x] + "RequestAnimationFrame"]
    window.cancelAnimationFrame = window[vendors[x] + "CancelAnimationFrame"] or window[vendors[x] + "CancelRequestAnimationFrame"]
    ++x
  unless window.requestAnimationFrame
    window.requestAnimationFrame = (callback, element) ->
      currTime = new Date().getTime()
      timeToCall = Math.max(0, 16 - (currTime - lastTime))
      id = window.setTimeout(->
        callback currTime + timeToCall
        return
      , timeToCall)
      lastTime = currTime + timeToCall
      id
  unless window.cancelAnimationFrame
    window.cancelAnimationFrame = (id) ->
      clearTimeout id
      return
  return
)()