Is setting of non-optional ivars demanded in all init methods? - initialization

Question

I'm trying to create an SKSpriteNode subclass. The plan was to let this handle most of the setup internally but annoyingly this seems to enforce quite a bit of code-duplication, in particular when setting up non-optional ivars and constants.
class TrollSpriteRegular : SKSpriteNode{
let head : SKSpriteNode
let body : SKSpriteNode
init(){
head = SKSpriteNode(color: SKColor.orangeColor(), size: CGSizeMake(60, 60))
body = SKSpriteNode(color: SKColor.purpleColor(), size: CGSizeMake(40, 60))
super.init()
}
// Desginated intiallizer
init(texture: SKTexture!, color: UIColor!, size: CGSize) {
head = SKSpriteNode(color: SKColor.orangeColor(), size: CGSizeMake(60, 60))
body = SKSpriteNode(color: SKColor.purpleColor(), size: CGSizeMake(40, 60))
super.init(texture: texture, color: color, size: size)
}
}
If I try to remove the creation of head or body from either one of the two initializers this results in a compiler error and I am unable to build. Is there any way to avoid this, or is perhaps the above patter not particularly swift-friendly?
I "need" the init method to allow creating new instances simply by using let trollSprite = TrollSpriteRegular().
Edit: OK the above can be simplified by defining the constants when they're declared.
class TrollSpriteRegular : SKSpriteNode{
let head = SKSpriteNode(color: SKColor.orangeColor(), size: CGSizeMake(60, 60))
let body = SKSpriteNode(color: SKColor.purpleColor(), size: CGSizeMake(40, 60))
...
If however I add a variable that should actually receive its value by an init-method I will have the same problem. e.g.:
let trollName : String
init(name :String){
trollName = name
super.init(texture: nil, color: nil, size: CGSizeZero)
}
This will force me to define trollName both in my own init(name:) and in the designated initializer. Oh, well.

Answer 1

A designated initializer is required to initialize all of the class's state. In a convenience initializer, you can just delegate that responsibility to a designated initializer.
However, in your case it looks like you want two designated initializers. But since these variables don't depend on any input into the initializer for their value, you can just define their value in their declaration. Here's the less repetitive version of that class:
class TrollSpriteRegular : SKSpriteNode {
let head : SKSpriteNode = SKSpriteNode(color: SKColor.orangeColor(), size: CGSizeMake(60, 60))
let body : SKSpriteNode = SKSpriteNode(color: SKColor.purpleColor(), size: CGSizeMake(40, 60))
}

Answer 2

This behavior is to be expected considering non optional variable can not be nil. If you're looking for a way to do all this more concisely, you can do the initialization of your variables inline using default values (colors and size). Then if you happen to have an initializer that needs to change one of these values, you could change the value of the sprite's color or size properties directly.
class TrollSpriteRegular: SKSpriteNode {
let head = SKSpriteNode(color: SKColor.orangeColor(), size: CGSizeMake(60.0, 60.0))
let body = SKSpriteNode(color: SKColor.purpleColor(), size: CGSizeMake(40.0, 60.0))
...
}