Q:

Swift: UIBezierPath bezierPathByReversingPath() Issues

I am using bezierPathByReversingPath() trying to make an animating circle. I finally found a method that will work, but I am getting this bar across the circle that is not being "deleted". 
The Code:
@IBDesignable class circle: UIView {

    override func drawRect(rect: CGRect) {
        let center = CGPoint(x:bounds.width/2, y: bounds.height/2)

        let circlePath : UIBezierPath = UIBezierPath(arcCenter: center, radius:
            CGFloat(250), startAngle: CGFloat(0), endAngle: CGFloat(360), clockwise: true)
        let circlePath2 : UIBezierPath = UIBezierPath(arcCenter: center, radius:
            CGFloat(200), startAngle: CGFloat(0), endAngle: CGFloat(360), clockwise: true)

        circlePath.appendPath(circlePath2.bezierPathByReversingPath())
        circlePath.fill() //appendPath(circlePath.bezierPathByReversingPath())    
    }
}

The Picture

P.S. If you want an example of what I am doing, it is a win/lose animation in the iOS game "Dulp".

A:

It is because UIBezierPath(arcCenter: center, radius: CGFloat(250), startAngle: CGFloat(0), endAngle: CGFloat(360), clockwise: true) takes radians, not degrees, as you specify here.
Thus, one would need to supply the arguments in radians.
I created a simple function that converts from degrees to radians; the result turned out fine.
Here is the function:
func degreesToRadians(degree : Int) -> CGFloat
{
    return CGFloat(degree) * CGFloat(M_PI) / 180.0
}

Usage:
let circlePath : UIBezierPath = UIBezierPath(arcCenter: center, radius: 250.0, startAngle: self.degreesToRadians(0), endAngle:    
                                             self.degreesToRadians(360), clockwise: true)

let circlePath2 : UIBezierPath = UIBezierPath(arcCenter: center, radius: 200.0, startAngle: self.degreesToRadians(0), endAngle:        
                                              self.degreesToRadians(360), clockwise: true)

Or one could create a protocol extension:
extension Double
{
    var degreesToRad : CGFloat
    {
        return CGFloat(self) * CGFloat(M_PI) / 180.0
    }
}

Usage:
let circlePath : UIBezierPath = UIBezierPath(arcCenter: center, radius: 250.0, startAngle: 0.0.degreesToRad , endAngle: 360.0.degreesToRad, clockwise: true)

let circlePath2 : UIBezierPath = UIBezierPath(arcCenter: center, radius: 200.0, startAngle: 0.0.degreesToRad, endAngle: 360.0.degreesToRad, clockwise: true)

