 
 import SwiftGraphics
 
-
 extension CGPoint : Geometry {
     public var frame:CGRect { get { return CGRect(center:self, diameter:0) } }
 }

        context.strokeSaltire(frame)
    }
}

            let rects:[CGRect] = points.map {
                return $0.frame
            }
            return CGRect.unionOfRects(rects)
        }
    }
