I've been developing a game that has been done in the single default GameScene created by XCode. Now I want to add more screens including a title screen that displays before the GameScene does and a 'Game Over' scene. The game over scene is transitioned from the GameScene and back and works fine but I cant get the title screen to display despite altering the code in GameViewController.swift:
class GameViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
//Original default code:
//if let scene = GameScene(fileNamed:"GameScene") {
//modified code
if let scene = Titles(fileNamed:"Titles") {
//<...more code...>
}
The app still runs but just displays a blank screen. I note that the GameScene file also has a GameScene.sks which I think is a graphical representation of the scene content. Do I need to create another .sks or link this to the new default scene even though the scene content is being added programmatically.
I could simply move all the code from GameScene to a new SKScene and use GameScene as the titles but I was curious about the problem and how to resolve it. Any ideas?
Many Thanks,
Kw
Yes - initialising a scene with 'fileNamed' refers to a .sks file, so you should create one.
In this line of code:
let scene = Titles(fileNamed:"Titles")
you are create a new scene object called scene of type Titles. This should match the class name in your swift file i.e. in titles.swift you should have:
class Titles: SKScene {
The fileNamed: is just one of many initialisers for SKSCene and this specifies a .sks file to load. If you want to place all content in your scene programmatically, perhaps use:
let scene = Titles(size: CGSize(width: 1536, height: 2048))
This question and it's accepted answer might help with any potential problems you might encounter - How to add an .sks files to existing Swift/Sprite-Kit project?
Related
I'm building a 3D game scene with SceneKit and I want to build like a "hud" over top, in order to get it kind of working, I built my ViewController by using a subview and overlaySKScene like so:
class ViewController:UIViewController {
var sceneView: SCNView!
var mainScene = MainScene() // <- SCNScene
var spriteScene: OverlayScene! // <- SKScene
override func viewDidLoad() {
super.viewDidLoad()
self.sceneView = SCNView(frame: CGRect(x: 0, y: 0, width: self.view.frame.width, height: self.view.frame.height))
self.sceneView.scene = mainScene
self.sceneView.backgroundColor = UIColor.clear
self.view.addSubview(self.sceneView)
self.spriteScene = OverlayScene(size: self.view.bounds.size)
self.sceneView.overlaySKScene = self.spriteScene
}
}
I've got a few questions about how this should be done the right way, as I'm running into some things that seem unusual.
First, lets say I need to do a segue, it doesn't seem clear to me how I would actually observe a tap on one of the SpriteKit nodes in the OverlayScene and then change controllers for the main parent ViewController. I haven't found any resources online that describe a similar situation.
Here is a trimmed down version of my OverlayScene:
import UIKit
import SpriteKit
class OverlayScene: SKScene {
var actionBarNode: SKSpriteNode!
override init(size: CGSize) {
super.init(size: size)
self.backgroundColor = UIColor.clear
self.actionBarNode = SKSpriteNode()
self.actionBarNode.size = CGSize(width: size.width, height: 100)
self.actionBarNode.position = CGPoint(x: size.width / 2, y: 50)
self.actionBarNode.color = .white
self.addChild(self.actionBarNode)
}
}
I am not answering your two questions directly, instead I will deal with your larger issue which is that you want a HUD on your game. A user interface. I never made a Scenekit game, but I did make a Spritekit game and the HUD is a clever trick. Let me explain.
Imagine you are standing behind a camera and looking through to see what the camera is seeing through its lens. You see the scene in front of it. Now take a piece of paper, cut out a rectangular box in the middle and draw on the remaining periphery. Tape this piece of paper to the front of the camera and look through. You still see the scene (a little smaller now), but now you also see the paper with the drawings. This is how HUDs work for the game.
I did some searching and both SpriteKit and SceneKit have a camera. In sceneKit you create a camera node and set the point of view of the scene to that camera. This represents the player looking out into the scene.
I am not sure if it works the same way in SceneKit, but in SpriteKit you can add nodes to the camera that will be locked in place. These become your HUD elements (buttons, score, etc). Since these are all child nodes of the camera they move when you move the camera so it feels like they are a static HUD. This is how you achieve a HUD. Read up on the documentation for SceneKit cameras as this will help you understand how to achieve the same effect.
I once also thought about doing it the way you are going now and it proved to be a very painful experience to mix SceneKit and SpriteKit so I would caution against it.
Also, while you can mix Interface Builder and SpriteKit I would caution against it. It basically ruined my first game into a buggy mess. If you do decide to use Interface Builder, try to limit it to menu screens and options screens. But, I found that programmatically creating everything gives you a much smoother, cleaner, and bug free experience.
Hope this helps!
I found a solution for my problem for anyone who may stumble into this same issue (which I think is likely as many examples demonstrate an overlay scene added as a subview in the manner I did.
First the tapHandler I had in my viewController needed to have the property cancelsTouchesInView set to false. This will allow the gesture to be received by the underlying views.
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(_:)))
tapGesture.cancelsTouchesInView = false
sceneView.addGestureRecognizer(tapGesture)
The reason this doesn't happen to all subviews is because I was relying on a view that was sized to 100% of the frame, covering the underlying ones, rather than just having the view occupy a smaller screen area, like a button or scoreboard as seen in the example docs.
Context
The default code that comes with a new SpriteKit game has a storyboard such that - following the launch screen - all there is, is a GameViewController which calls forth the GameScene. However, this may be less ideal for many games. For example, one may wish to have the user select difficulty from a main menu, and then go to the GameScene - outlined below:
Notably, the middle view controller is a custom class MyUIViewController so that the UIButtons "easy" and "hard" can have the following IBActions:
#IBAction func setGameDifficultyToEasy(sender: AnyObject) {
gameDifficulty = "easy"
print("Game difficulty set to \(gameDifficulty)")
}
#IBAction func setGameDifficultyToHard(sender: AnyObject) {
gameDifficulty = "hard"
print("Game difficulty set to \(gameDifficulty)")
}
where gameDifficulty is a global variable, that the GameScene utilizes to determine aspects of the game play.
In the M.W.E. setting gameDifficulty to "hard" causes there to be three sprites on the screen, whereas setting gameDifficulty to "easy" puts forth only two.
Easy
Hard
Question
In the following gif, one sees that:
gameDifficuly is initialized as "hard"
the UIButton "Easy" was selected.
This can be seen be the printout statements.
Interestingly, although the UIButton was pressed first then the GameViewController was called, the changing of the parameter gameDifficulty was not set until after the GameScene was rendered.
**How can I get the UIButtons to set the parameter gameDifficulty prior to GameScene being called?
Minimum Working Example
Stack Overflow SKSpriteKit
Note
My answer here shows that this is clearly possible, but by relegating everything to SKViews rather than using a storyboard. So if possible, please keep answers related to using storyboards.
I've been developing a game using SpriteKit and Swift but I seem to be having trouble determining what the real differences are between the GameViewController and any one of my SKScenes. I'm trying to understand the differences because I want to implement a GameCenter or local leaderboard into my game but in all the tutorials I find (like this one:Game Center Leaderboards! (Swift 2 in Xcode) ) they have all the logic in GameViewController as they are working with single view apps. I'm having trouble understanding the relation when I read the docs, so any help would be great. Ultimately, I want to be able to display and push data to and from GameCenter in one of my scenes such as GameOverScene. Thanks for any help!
Here is some good info to start with:
Diagram of what happens each frame in SK:
So you see, the SKScene is the class with all of the fun stuff like Nodes and Actions, and is where everything (important to you) happens. You can generate these scenes through the Editor, but then you probably need to make a new .swift file to go with it (as each scene can have its own logic).
The editor is just a 'shortcut' to initializing a bunch of stuff, and honestly, you can make complete games with little code (but you very quickly find out that you want more)
So in this code, where you declare GameScene or PauseScreen (which are basically just class declarations, that inherit from SKScene), you quickly find this line talking about something that ISNT a scene:
override func didMoveToView(view: SKView)
.. it's calling a SKView... what is that, and where did it come from?
(Read about SKView here, and look at its inheritance):
https://developer.apple.com/library/ios/documentation/SpriteKit/Reference/SKView/index.html#//apple_ref/occ/cl/SKView
We find this SKView declaration in the GameViewController file, (which is just a class), notice that it's the same as the regular iOS apps mostly, as it inherits UIViewController:
override func viewDidLoad() {
super.viewDidLoad()
if let scene = GameScene(fileNamed:"GameScene") {
// Configure the view.
let skView = self.view as! SKView
skView.showsFPS = true
skView.showsNodeCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
skView.ignoresSiblingOrder = true
/* Set the scale mode to scale to fit the window */
scene.scaleMode = .AspectFill
skView.presentScene(scene)
}
Again, that method is declared in GameViewController.swift, which is basically just this:
class GameViewController: UIViewController
So how does all of this relate to iOS apps and SpriteKit? Well, they are all mashed on top of each other:
IOS app anatomy:
Basically, from right to left, you have the Window, which is (correct me if wrong) the AppDelegate, then the ViewController, then your View, which has all of the cool stuff in it (Storyboards sit inside of the View, just as SKScenes sit inside of the View.... Labels, Nodes, or Buttons, all sit inside of their respective classes ((the view)))
It's all a big sandwich of inheritance.
Check out the Apple websites for more info.
https://developer.apple.com/library/safari/documentation/UserExperience/Conceptual/MobileHIG/ContentViews.html#//apple_ref/doc/uid/TP40006556-CH13-SW1
https://developer.apple.com/spritekit/
https://developer.apple.com/library/ios/documentation/SpriteKit/Reference/SpriteKitFramework_Ref/
https://developer.apple.com/library/safari/documentation/UserExperience/Conceptual/MobileHIG/Anatomy.html
Basically, everything is an Class inherited from a class inherited from a class and so on, so on... It can get messy. You can also see these inheritances in Xcode by CMD+clicking on them, which will jump you to the source file.
Goodluck with your studies and adventures in SpriteKit :)
You should only have a single GameViewController in your game. SKScenes are the scenes that the game transitions in between an to.
For example, the home menu screen? That's an SKScene. The main gameplay? That's an SKScene. The gameover screen? That's an SKScene.
The GameViewController initializes the entire view that the game will be maintained in, so the view. The SKScenes are just scenes that are placed on top of the view. You should be looking at a tutorial that uses SKScenes.
Here's how to make game center work as of the latest Swift 2.2.
Add this function anywhere inside the GameViewController class, and then just call it right after super.viewDidLoad().
func authenticateLocalPlayer() {
let localPlayer = GKLocalPlayer.localPlayer()
localPlayer.authenticateHandler = {(viewController, error) -> Void in
if (viewController != nil) {
self.presentViewController(viewController!, animated: true, completion: nil)
}
else {
print((GKLocalPlayer.localPlayer().authenticated))
}
}
}
Add the following functions in your SKScene class file. Don't forget to import GameKit. Just call showLeader() whenever you want the leaderboard to be displayed.
func showLeader() {
let viewControllerVar = self.view?.window?.rootViewController
let gKGCViewController = GKGameCenterViewController()
gKGCViewController.gameCenterDelegate = self
viewControllerVar?.presentViewController(gKGCViewController, animated: true, completion: nil)
}
func gameCenterViewControllerDidFinish(gameCenterViewController: GKGameCenterViewController) {
gameCenterViewController.dismissViewControllerAnimated(true, completion: nil)
}
And this is a sample I have of how the score is saved to game center.
func saveHighscore(gameScore: Int) {
print("Player has been authenticated.")
if GKLocalPlayer.localPlayer().authenticated {
let scoreReporter = GKScore(leaderboardIdentifier: "YOUR_LEADERBOARD_ID")
scoreReporter.value = Int64(gameScore)
let scoreArray: [GKScore] = [scoreReporter]
GKScore.reportScores(scoreArray, withCompletionHandler: {error -> Void in
if error != nil {
print("An error has occured: \(error)")
}
})
}
}
It all depends about how you are designing your app, and what technologies you want to use.
If you are looking to build an app in 100% Sprite Kit, then you treat your UIViewController as a shell that holds your Sprite Kit app. The only time you should be touching this is when you need to do things that the SpriteKit scene shouldn't be doing, like creating gesture controls and what not.
However, there are uses to having multiple view controllers with sprite kit elements. Perhaps you are making a business application, and decide to include a little game to go with it.
IMO the best way to think about it in terms of web design is think of your View controller as your HTML page, and think of your Scene as your flash/silverlight/unity/etc game player that you embed in the website. Sometimes you want that player to be full screen, some times you do not, it comes down to the design of the application. When in full screen, we do not need any other components, so the player can do all the work. But what if we attach a how to guide link on the page. We wouldn't want this in game, we want this outside of it. This link will then open up a new page, not associated with the old page, and has no use for the game player components.
Now for your situation with Game Center, it gets more complicated. Game Center was built before Sprite Kit came to existence, so all of its functionality is built on UIKit. But Game Center also allows for customization, so you do not have to use the UIKit features of it. Of course, you will have to do all of the work then in displaying the information inside of your scene with Sprite Kit objects.
To make life easiest for you, you would include all of the built in code needed into your View Controller, then what you do is create a delegate that the scene knows about, and assign your view controller to this delegate. Now Game Scene can access any element of that view controller that you allow, like presenting leader boards or passing up leader boards. Check out this tutorial in its entirety, it will help you learn all you will need to achieve what you want.
https://www.raywenderlich.com/115300/swift-2-tutorial-part-3-tuples-protocols-delegates-and-table-views
In MVC the controller acts as a coordinator, a bit like the conductor in an orchestra. My preference is that scenes just do the one thing they were designed for i.e. implement game play. When a scene is completed, the final task is to notify the controller (using delegate pattern) that the scene is complete. It is then up to the controller to decide what happens next i.e. transition to next scene or game over.
When using Xcode, I've faced the annoying problem, which is Xcode always crashes when I click .SKS files. I have raised questions here, and even in Apple developer forum, as well as searched for the solutions on the Internet... but it is hopeless.
Because I am making a game with many scenes, so if I can't use SpriteKit editor to interact with the scenes in an easy way, I want to know how can I interact with my scenes by coding their .swift files.
So the question is, for example, when I create a file "EndScene.sks", how can I create a "EndScene.swift", which links with my .sks file?
Thank you very much!
Create a new swift file and name it the same as your .sks file. Let's say you have a .sks file called MainMenu.sks. You'd create a swift file called MainMenu.swift. Inside that file, you'll want to create a Main Menu class that inherits from SKScene.
import SpriteKit
class MainMenu: SKScene {
}
Inside there is where you'll put all your code. The key is, as you said, linking this to the .sks file.
When you go to present your scene, you'll instantiate the class and associate it with the .sks file.
import UIKit
import SpriteKit
class GameViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
if let scene = MainMenu(fileNamed:"MainMenu") {
let skView = self.view as! SKView
// Some settings applied to the scene and view
// ... code ...
skView.presentScene(scene)
}
}
//... other code
}
Note the line let scene = MainMenu(fileNamed:"MainMenu"). That's where you are instantiating the class you created in MainMenu.swift. So, technically, MainMenu() is the .swift file and fileNamed: "MainMenu" is the .sks file. You can technically put any .sks file into the init call and it'll render that scene.
Imagine having a game with all the logic for a maze runner. You could build all the game logic in a class called MazeScene and just make a bunch of .sks files, each with a different maze. You could then so something like, MazeScene(fileNamed: "MazeOne") or MazeScene(fileNamed: "MazeThree").
For the documentation on this, SKScene inherits from SKNode so you'll find the documentation for init(fileNamed:) here
That should get you going.
So instead of commenting I have to wander because StackOverflow won't let me comment, how much of this is the same in swift 3? And when you were doing this in the UIViewController you said
if let scene = MainMenu(fileNamed:"MainMenu") {
let skView = self.view as! SKView
// Some settings applied to the scene and view
// ... code ...
skView.presentScene(scene)
}
What do you mean by
// ... code ...
Do we put all of the code we would put in the SKScene class in there instead? I thought the whole point was to have a separate SKScene class. And when I try it like that the SKScene class I have doesn't load. Thanks for any clarification and sorry I have to answer instead of comment. It's pretty stupid that you need 50 reputation to leave a comment I don't see any point in that. Anyway, Thanks!
I just created a new SpriteKit project, and right out of the door bam! problem. I ran the project without touching anything, and as it should be, the default hello world project appeared. All good on that front. Now, I created a new Coco Touch Class and named it test with the superclass of SKScene. Then, in the GameViewController, I changed ONLY the following line
if let scene = GameScene(fileNamed: "GameScene") {
to
if let scene = GameScene(fileNamed: "test") {
and the game crashed on load.
Am I messing up somewhere when I create the new scene, did I miss something? Any suggestions would be helpful, thanks.
Thats because that line of code of code runs an initializer that unarchives a file from a .sks file, which you didn't create yet for the scene. You probably have a GameScene .sks configured but not a test.sks.
You need to create a .sks file if you want to initialize your first scene like that. Otherwise, just create a scene without unarchiving .sks using SKScene initializer initWithSize: