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  p Drop an audio file here
  small (or click anywhere to show the open file dialog)
input#musicFile(type='file', accept='audio/*')


  background: #000
  margin: 0
#visualizer canvas
  width: 100%
  height: 100%
  position: fixed
  top: 0
  left: 0

  position: fixed
  z-index: 2
  color: #FFF
  text-align: center
  width: 100%
  background: rgba(0,0,0,.7)
  padding-bottom: 1em
  top: 40vh
  transition: opacity 1s ease-in-out
  cursor: default
  position: fixed
  z-index: 10
  width: 100%
  height: 100%
  opacity: 0


# Graphics 
w = window.innerWidth
h = window.innerHeight
baseRotation = 0
# Create a Renderer
renderer = PIXI.autoDetectRenderer w, h, { antialias: true }
center = new PIXI.Point w/2, h/2
# Append it to #visualizer
document.getElementById 'visualizer'
.appendChild renderer.view
# Create a stage
vis = new PIXI.Container()
vis.interactive = true
# Create an array of numbers (frq data)
data = (64 for [0..128])
# Create 23 graphics (to render the lines)
lines = (new PIXI.Graphics() for [0..23])
for line in lines
  vis.addChild line

  baseRotation += 0.0025
  # Draw 23 lines
  for i in [0..23]
    line = lines[i]
    line.position = line.pivot = center
    line.lineStyle 8, 0x00CC00, 1
    line.moveTo w/2,h/2
    # Each line represents an element in the data array
    line.lineTo w/2-data[i*5]+64,h/2-data[i*5]+64
    line.alpha = 0.005*data[1*5]
    line.rotation = baseRotation + 0.2617993878*i
  renderer.render vis

# Resize the canvas when the window resizes
window.onresize = ->
  w = window.innerWidth
  h = window.innerHeight
  center = new PIXI.Point w/2, h/2
  renderer.resize w,h
# Audio 
context = new (window.AudioContext || window.webkitAudioContext)()
analyser = context.createAnalyser()
analyser.fftSize = 256
bufferLength = analyser.frequencyBinCount
# Create an empty audio source
source = context.createBufferSource()
analyser.connect context.destination
# Get the file element
fileElement = document.getElementById 'musicFile'
file = undefined
# Start when a file is chosen
fileElement.addEventListener 'change', ->
  reader = new FileReader()
  reader.onload = (ev)->
    # Decode and load the audio file
    context.decodeAudioData, (buffer)->
      source = context.createBufferSource()
      source.loop = true
      source.connect analyser
      document.getElementById('fileTooltip').style.opacity = 0
      source.buffer = buffer
      # Configure the analyser and reinitialize the data array
      data = new Uint8Array analyser.frequencyBinCount
  reader.readAsArrayBuffer @files[0]

# Main Loop
update = ()->
  requestAnimationFrame update
  if source.buffer
    analyser.getByteTimeDomainData data
# Start the loop