         }
     }
     
-    @IBInspectable
-    public var rateMouthVerticalPosition: CGFloat = 0.35 {
+    /// Mouth vertical position. From 0.1 to 0.5.
+    @IBInspectable public var rateMouthVerticalPosition: CGFloat = 0.35 {
         didSet {
             if rateMouthVerticalPosition > 0.5 {
                 rateMouthVerticalPosition = 0.5

        }
    }
    
    @IBInspectable
    public var rateShowEyes: Bool = true {
        didSet {
            self.setNeedsDisplay()
        }
    }
    
    @IBInspectable
    public var rateEyeWidth: CGFloat = 0.2 {
        didSet {
            if rateEyeWidth > 0.3 {
                rateEyeWidth = 0.3

        facePath.stroke()
    }
    
    /**
    Draw mouth.
    
    - parameter rect: frame
    */
    private func drawMouthWithRect(rect: CGRect) {
        let width = CGRectGetWidth(rect)
        let height = CGRectGetWidth(rect)
