init() vs didMove vs sceneDidLoad in SpriteKit

Question

I understand that there are 3 ways to create a scene in SpriteKit, init(), didMove, and sceneDidLoad.
But I can't understand to separate the 3 ways. Reading other questions I understood the order to call is init -> SceneDidLoad -> didMove.

How can I use them to use effectively?

Answer 1

You're right about the order those functions are called in. But only init(size:) actually creates a scene.

init(size:) initializes a new scene object with the given CGSize as its bounds. Anything that must be set up prior to the scene becoming visible should happen here. That's the important bit because a newly initialized scene isn't visible to the user until it's presented by a view.

sceneDidLoad() is called as a result of init(size:) and can be used to do any more setup required before the scene is presented. init(size:) can be called from wherever you want to make a new scene, but sceneDidLoad() happens in the scene itself. This is useful for any setup that you want all scenes of this class to use.

didMove(to:) is different because it doesn't have to do with the initialization. This function is called when the scene is presented by a view. Basically, when it becomes visible to the user. UI adjustments and layout for elements inside the scene are typically handled here.