Draw hats!

LiveCaptureHattingViewController.swift

let rect = observation.boundingBox.denormalized(newRect: self.view.frame)

let hatWidth = rect.size.width
let hatHeight = rect.size.height
let hatX = rect.origin.x - hatWidth/4
let hatY = rect.origin.y - hatHeight
let hatRect = CGRect(x: hatX, y: hatY, width: hatWidth, height: hatHeight)

var hat : UIImageView? = nil
if faceNumber >= self.hats.count {
    hat = UIImageView(frame: hatRect)
    hat!.image = UIImage.init(named: "hat")
    self.hats.append(hat!)
}
else {
    hat = self.hats[faceNumber]
    hat!.frame = hatRect
}

self.view.addSubview(hat!)
hat!.isHidden = false