Rainbow drawing

Code

var bg = new Path.Rectangle({
    size: view.size,
    fillColor: 'black'
})

function createCircle(x, y){
  var circle = new Path.Circle({
    center: [x,y],
    radius: 40,
    fillColor: "#FFFD54",
  })

  circle.onFrame = function(event){
    this.fillColor.hue += 1
  }

  return circle
}

function onMouseDrag(event){
  createCircle(event.point.x, event.point.y)
}