Sprite Kit Scenes and SKNode Positioning - Beginning Swift Games Development for iOS - page 29

println("The size is (\(size.width), \(size.height)).")
Now run the application again using the iPhone 4s simulator. After you do, look in the
console window. You will see the following output:
The size is (320.0, 480.0).
This is the size of the scene running on an iPhone 4s. You can try this again running on
either of the iPhone 5 or 6 simulator. These values tell you the size of your scene (the
viewport into your game world).
If you want to position SKNode objects into the visible world of your game, you have to
set their positions inside the range of (0, 0) to (320, 480) on the iPhone 4s or from (0, 0) to
(320, 568) on the iPhone 5s. Take a moment and play around with the coordinate system.
Go back to the GameScene.init() method and change the position of the player-
Node using the following line:
playerNode!.position = CGPoint(x: size.width / 2, y:
size.height / 2)
With this change, you are positioning the playerNode in the center of the scene. To see
the position change, run the app in the simulator again. You will now see your player in
the middle of your scene, as shown in Figure 2-7 .