multi touch drag the dots

gistfile1.coffee

  pos = [0,0]
  origin = [0,0]
  init = ->
    $('.dot').on 'touchstart': startDrag
  startDrag = (event)=>
    dot = $ event.currentTarget
    dot.on
      'touchmove': moveDrag
      'touchend': endDrag
    offset = dot.offset()
    pos = [offset.left, offset.top]
    origin = getCoors event
  
  moveDrag = (event)=>
    event.preventDefault()
    dot = $ event.currentTarget
    currentPos = getCoors event
    deltaX = currentPos[0] - @origin[0]
    deltaY = currentPos[1] - @origin[1]
    dot.css
      left: ((@pos[0] + deltaX) + 30) + 'px'
      top: ((@pos[1] + deltaY) + 30) + 'px'
  endDrag = (event)=>
    dot = $ event.currentTarget
    dot.off
      'touchmove': moveDrag
      'touchend': endDrag
  getCoors = (e)->
    event = e.originalEvent
    coors = []
    if event.targetTouches and event.targetTouches.length
      thisTouch = event.targetTouches[0]
      coors[0] = thisTouch.clientX
      coors[1] = thisTouch.clientY
    else
      coors[0] = event.clientX
      coors[1] = event.clientY
    coors