CoffeeScript iPad Orientation and Motion detection

iPadOrientationAndMotionDetection.coffee

updateInputField = (el, value) ->
  el.value = value
  value += 10
  el.setAttribute "style", "width:" + Math.round(value * 25, 10) + "px"
moveThing = (el, acc) ->
  acc.x = Math.round(acc.x * 20)
  acc.y = Math.round(acc.y * 20)
  acc.z = Math.round(acc.z * 25)
  attr = "-webkit-transform:translate3d(" + acc.x + "px," + acc.y + "px," + acc.z + "px);"
  attr += "-webkit-transition-duration:0.1s"
  el.setAttribute "style", attr

accTrackObj = (options) ->
  acc = {}
  accHistory = [ {}, {} ]
  fake = ->
    x: accHistory[0].x - accHistory[1].x
    y: accHistory[0].y - accHistory[1].y
    z: accHistory[0].z - accHistory[1].z
  
  ondevicemotion = (e) ->
    acc = e.accelerationIncludingGravity
    accHistory[1] = accHistory[0]
    accHistory[0] = 
      x: acc.x
      y: acc.y
      z: acc.z
    
    options.ondevicemotion and options.ondevicemotion(acc, accHistory)
    options.fake and options.fake(fake())
  
  onorientationchange = ->
    orientationDeg = window.orientation
    orientationName = (if (orientationDeg == 90 or orientationDeg == -90) then "Landscape" else "Portrait")
    options.onorientationchange and options.onorientationchange(orientationName, orientationDeg)
  
  @start = ->
    window.ondevicemotion = ondevicemotion
    window.onorientationchange = onorientationchange
  
  @stop = ->
    window.ondevicemotion = null
    window.onorientationchange = null

myAcc = new accTrackObj(
  ondevicemotion: (acc) ->
    updateInputField x, acc.x
    updateInputField y, acc.y
    updateInputField z, acc.z
    moveThing thing2, acc
  
  fake: (acc) ->
    moveThing thing1, acc
)
window.onload = ->
  x = document.getElementById("x")
  y = document.getElementById("y")
  z = document.getElementById("z")
  thing1 = document.getElementById("thing1")
  thing2 = document.getElementById("thing2")

iPadTest.html

  <div class="thing" id="thing1">reacts to sudden movement</div>
  <div class="thing" id="thing2">reacts to orientation</div>
  <form onsubmit="return false;">
    <button onclick="myAcc.start()">Start</button>
    <button onclick="myAcc.stop()">Stop</button>
    <br><label>x<input id="x"></label>
    <br><label>y<input id="y"></label>
    <br><label>z<input id="z"></label>
  </form>

Here's some prior work related to this:

iPad orientation detection
http://jsbin.com/emunu5/6/edit

Björn Söderqvist's motion detection for iPad in JS
http://jsbin.com/ogeha5/2/edit