       timeScale *= TIME_SCALE_SPEED
     if e.keyCode == 189
       timeScale /= TIME_SCALE_SPEED
-    if e.keyCode == 37 || e.keyCode == 65
-      offset = offset.add new Vector(PAN_SPEED, 0)
-    if e.keyCode == 38 || e.keyCode == 87
-      offset = offset.add new Vector(0, PAN_SPEED)
-    if e.keyCode == 39 || e.keyCode == 68
-      offset = offset.add new Vector(-PAN_SPEED, 0)
-    if e.keyCode == 40 || e.keyCode == 83
-      offset = offset.add new Vector(0, -PAN_SPEED)
-    rotation = ((rotation%(Math.PI*2))+(Math.PI*2))%(Math.PI*2)
 
   ctx = $('canvas')[0].getContext '2d'
 

  PARTICLE_COUNT = 100
  MIN_MASS = 1
  MAX_MASS = 10
  PAN_SPEED = 10
  ROTATE_SPEED = 0.001
  SCALE_SPEED = 0.001
  TIME_SCALE_SPEED = 1.1

  width = window.innerWidth


    rotation += ROTATE_SPEED * deltaTime if Keyboard.isDown 69
    rotation -= ROTATE_SPEED * deltaTime if Keyboard.isDown 81
    rotation = ((rotation%(Math.PI*2))+(Math.PI*2))%(Math.PI*2)
    scale *= 1 + ZOOM_SPEED * deltaTime if Keyboard.isDown 88
    scale /= 1 + ZOOM_SPEED * deltaTime if Keyboard.isDown 90
    offset = offset.add new Vector(PAN_SPEED * deltaTime, 0) if Keyboard.isDown 65
    offset = offset.add new Vector(0, PAN_SPEED * deltaTime) if Keyboard.isDown 87
    offset = offset.add new Vector(-PAN_SPEED * deltaTime, 0) if Keyboard.isDown 68
    offset = offset.add new Vector(0, -PAN_SPEED * deltaTime) if Keyboard.isDown 83

    ctx.clearRect 0, 0, width, height
    ctx.translate width/2, height/2
