Simple collection rotator for slideshows, quotes

rotator_builder.js.coffee

jQuery ->
  # rotate items

  rotator_builder = (selector, args) ->
    trans_in = args.trans_in || "fadeIn"
    trans_out = args.trans_out || "fadeOut"
    trans_in_dur = args.trans_in_dur || 1000
    trans_out_dur = args.trans_out_dur || 400
    show_dur = args.show_dur || 7000

    $items = $(selector)
    num_items = $items.length
    cur = 0
    prev = num_items - 1
    loop_fn = () ->
      cur %=  num_items
      prev %= num_items
      $($items[prev])[trans_out] trans_out_dur
      $($items[cur]).delay(trans_out_dur+50)[trans_in](trans_in_dur) 
      # need that +50 to make sure there's no overlap and the prev item is completely gone
      cur++
      prev++
      setTimeout loop_fn, show_dur
    loop_fn

  ############################################
  # Example
  looper = rotator_builder "#stuff li",
    trans_in: "fadeIn",
    trans_out: "fadeOut",
    trans_in_dur: 1000,
    trans_out_dur: 400,
    show_dur: 7000

  looper()