title: Swift Compiler error: 'Double' is not convertible to CGFloat
body: <p>I just began learning Swift. I created a game project and a template came up. I have not done anything to the code whatsoever. I tried to run the project but a compiler error popped up.</p>
  
  <p>I'm going off a tutorial so it could be something wrong with my environment or the book is already outdated. </p>
  
  <p>Swift Compiler error: 'Double' is not convertible to CGFloat</p>
  
  <pre><code>import SpriteKit
  
  class GameScene: SKScene {
      override func didMoveToView(view: SKView) {
          /* Setup your scene here */
          let myLabel = SKLabelNode(fontNamed:"Chalkduster")
          myLabel.text = "Hello, World!";
          myLabel.fontSize = 65;
          myLabel.position = CGPoint(x:CGRectGetMidX(self.frame), y:CGRectGetMidY(self.frame));
  
          self.addChild(myLabel)
      }
  
      override func mouseDown(theEvent: NSEvent) {
          /* Called when a mouse click occurs */
  
          let location = theEvent.locationInNode(self)
  
          let sprite = SKSpriteNode(imageNamed:"Spaceship")
          sprite.position = location;
          sprite.setScale(0.5)
  
          let action = SKAction.rotateByAngle(M_PI, duration:1)
          sprite.runAction(SKAction.repeatActionForever(action))
  
          self.addChild(sprite)
      }
  
      override func update(currentTime: CFTimeInterval) {
          /* Called before each frame is rendered */
      }
  }
  </code></pre>
  
  <p>The error occurs in <code>let action = SKAction.rotateByAngle(M_PI, duration:1)</code></p>
  
  <p>Here is a screenshot of the project settings
  <img src="https://i.stack.imgur.com/UwroR.png" alt="enter image description here"></p>