UIBezierPath+Polygons.swift - UIBezierPath Swift extension for easy creation of polygon paths!

UIBezierPath+Polygons.swift

//
//  UIBezierPath+Polygons.swift
//
//
//  Created by Txai Wieser on 11/05/15.
//  Copyright (c) 2015 TDW. All rights reserved.
//  Based on: https://github.com/ZevEisenberg/ZEPolygon, thanks man!

import UIKit

extension UIBezierPath {
    convenience init(polygonIn rect:CGRect, sides:Int) {
        self.init()
        if sides < 3 {
            assertionFailure("To build a polygon you need 3 ou more sides")
        }
        
        let xRadius = CGRectGetWidth(rect)/2
        let yRadius = CGRectGetHeight(rect)/2
        
        let centerX = CGRectGetMidX(rect)
        let centerY = CGRectGetMidY(rect)
        
        self.moveToPoint(CGPoint(x: centerX + xRadius, y: centerY + 0))
        
        for i in 0..<sides {
            let theta = CGFloat(2*M_PI)/CGFloat(sides) * CGFloat(i)
            let xCoordinate = centerX + xRadius * cos(theta)
            let yCoordinate = centerY + yRadius * sin(theta)
            self.addLineToPoint(CGPoint(x: xCoordinate, y: yCoordinate))
        }
        self.closePath()
    }
}