app crashes when transitioning to original scene swift sprite kit - ios

I am building an app that transitions to an end scene when two object collide. That part works just fine, but when i try to transition back to the original scene with the restart button on the end scene.The app crashes. It makes it back to the original scene but crashes immediately.The the line that is selected in the debugger is where i declare the physics body of one of the objects that collide(works fine first run. I have seen this error many times. But no one can give me an answer of how to fix it. Here is the code where i transition from the original seen to the end scene
func mineSubCrash(Mine : SKSpriteNode, subm: SKSpriteNode){
subm.removeFromParent()
Mine.removeFromParent()
self.view?.presentScene(RestartScene())
}
very basic, here is the transition back
func restart(){
restartButton.removeFromSuperview()
self.view?.presentScene(GameScene(), transition: SKTransition.fadeWithDuration(0.3))
}
I dont understand why it crashes. must be something with me not ending the original scene right . I have had this problem with other apps i have tried to make. help needed and appreciated!!

Related

How do I freeze an AR scene in ARKit and then restore the scene elsewhere - Swift, XCode

I have an AR scene (built as a node with children nodes) that I want the user to walk inside it.
Because it can be large, I added a pause button in the corner so that if the user hits an obstacle in the real world, he'll just need to press-and-hold that button to freeze the scene, move elsewhere in the real world, and when the button will be released the scene would have moved as-is to that new location, retaining the same relative position and rotation inside that scene.
What I did is very simple. When button is touched down I just did:
sceneView.session.pause()
And when the button is Touch Up Inside I ran:
sceneView.session.run(configuration)
This seemed to do the trick.
However, after I clicked and moved once or twice more and moved back to where I was before, my whole AR scene suddenly jumped back to its previous location in the real world. So it did freeze and showed up in the new location for a second or two, but then it jumped back.
I tried to resume the session with several of the available options.
If I ran:
sceneView.session.run(configuration, options: [.resetTracking])
the whole scene would move to the new location, but it would be set to its initial position and rotation as if I was standing at (0,0,0) when I started the app, but now moved to the new location. In other words, it lost the current location and rotation that I was at when I pressed the pause button and just reset the scene.
All the other options that I tried had the same effect as if I didn't add any options.
I should add that I'm not using any anchors (so far) nor any ray casting.
I didn't try different combinations of those options (except removeExistingAnchors and resetTracking together), but I doubt that that would help. Am I wrong?
What am I doing wrong?
Anyone have a solution for my problem?
Or will I need to manually record the current position and rotation when pressing the pause button and then restore those with some position change of the node? I was hoping I could skip having to do it this way.
And if I do need to do it manually, any tips on how to achieve this?
Thanks for your help!

'Play on' feature is an in-app purchase? SpriteKit/Swift

I'm near the end of developing a game, and long story short, the game will be over when an object crashes into one of the obstacles. I've got that part down and the game runs really well by itself, but there is one more step I am looking to add in.
I would like to add in an in-app purchase of a 'play on' feature, that is, starting where the user's game originally ended so they can continue on. I'm okay with in-app purchases on the whole, but I guess what I want to know is how does one make it possible to 'play on' following the in app purchase? I'm just looking for something basic I can build on.
I'm a Stack newbie, as I've only created an account today (but I've been programming for a little while and this site has helped me so many times), so I'm sorry if there has been a duplicate thread made elsewhere. I did look around for an hour or so before deciding to post (and Google was no help).
As a general stack overflow rule you should always post some of your own code or what code you have played around with.
I am actually also looking to integrate a playOn button in my game. Now I haven't actually found the perfect solution for this yet but hopefully this helps you get on the right track.
Step 1:
How have you programmed your game over scenario?
Are you just pausing the scene, are you pausing nodes or are you removing all children from your scene?
The way I pause my scene is by creating a worldNode and than adding all objects that I need paused to the worldNode.
You can read my two answered questions for more detail
Keeping the game paused after app become active?
Sprite moves two places after being paused and then unpaused
This way when I pause my game I dont actually pause the scene which gives me more flexibility adding pauseMenus etc. Furthermore its seems smoother than pausing the skView.
I also call pause when the player died, which means I could resume the enemies/obstacles from where they left of if I call resume.
So my game over method looks like this
func gameOver() {
pause() // call pause method to pause worldNode etc
//show game over screen including playOn button
}
Step 2:
Now in regards to respawning the player, it depends on how he is positioned, how far he can move etc.
If your player is mostly in the same area than you can probably just respawn you player manually once "PlayOn" is pressed and than resume the game as if it was just paused.
So once your playOn button is pressed you can call a method like so
func playOnPressed() {
// Remove current player
// Doesnt have to be called, you could just change the position
player.removeFromParent()
// Add player manually again to scene or just reposition him
...
// Remove obstacle that killed player
// haven't found a great solution for this yet
// You could make the player not receive damage for 5 seconds to make sure you dont die immediately after playOn is pressed
// Call resume method, maybe with delay if needed
resume()
}
If your player position could be all over the screen, as in my game, I have been playing around with a few things so far.
I created a position property to track the player position
playerPosition = CGPoint!
and than in my scene update method I constantly update this method to the
actual position of the player.
override func update(currentTime: CFTimeInterval) {
if gameOver = false {
playerPosition = player.position
}
}
I than have been playing around with the "playOnPressed" method,
func playOnPressed() {
// Remove current player
//Doesnt have to be called, you could just change the positioon
player.removeFromParent()
// Add player manually again to scene or just reposition him
...
player = SKSpriteNode(...
player.position.x = playerPosition.x - 40 // adjust this so it doesnt spawn where he died but maybe a bit further back
player.position.y = playerPosition.y // adjust if needed
// Remove obstacle that killed player
// haven't found a great solution for this yet
// You could make the player not receive damage for 5 seconds to make sure you dont die immediately after playOn is pressed
// Call resume method, with delay if needed
resume()
}
I hope this helps you playing around with your playOn button, if someone has a better way I would also appreciate it immensely.

App crashes transitioning scenes swift sprite kit

I am building an app that has a main scene and a restart scene. The main game scene uses sprite kit physics to have an object controlled by the user float across the screen. When it rashes into an obstacle the app transitions to the end scene using:
self.presentScene.restartscene.
This works just fine. then the restart scene has a restart button. when this is clicked the app transitions back to the game scene using:
self.presentscene.gamescene
i know this presents the original scene because i did an ns log to make sure. The problem is when this original scene is presented again the scene changes colors multiple times alternates very quickly between one and two nodes on the screen and then crashes. I have no idea the cause. i have had this problem before and i know other people have. no one has given me a definite answer. i hope one of you guys will. Thank you. help needed badly!!!!!!!
Try to navigate between scenes this way:
let nextScene = GameScene(fileNamed: "SceneNameHere")!
scene?.view?.presentScene(nextScene)
Also please check your code on startup in the gamescene.
May be you are using some global flags to store value for win/fail/restart conditions and your scenes simply open together one by one (it is hard to say without checking actual code).
You need to remove the original seen from view after transitioning away from it. Use this code:
myView.removeFromParentViewController()
Hope this helps :)

Presenting a new viewController doesn't seem to unload the previous

The game I'm developing consists of a Main Menu, and Game viewController separately.
However when moving from the game screen to the menu screen, it seems as if the class files from the previous viewController are still in effect?
For example, players start the game by tapping anywhere on the screen whilst in the game viewController, which causes a new bar to be "launched", which in turn plays a small tone which varies depending on the direction. However when returning to the main menu after the game is over (achieved by pressing a button to present the menu viewController), tapping anywhere on the menu screen seems to start the game again from the game viewController?
By this, I mean the bar launch sound is played, despite there being no code available in the main menu viewController to play said sound, pressing play on the menu will take you to the game screen, where the game has been reset, until tapping again, where the sound plays implying a new bar is launched, despite all images being invisible.
I made sure that, when leaving any view, I wipe all subviews from the view, so that whenever the screen is loaded there's nothing being covered up. I also tried dismissing the previous view controller, however nothing seems to take effect. So, I can't tell for certain whether the views are being removed or what... It's simply mind breaking to me.
Unfortunately my descriptions most likely aren't doing myself any justice, so hopefully this video demonstration will help out. Note that at the beginning, I am tapping the screen to show that no sound is played, however of course that won't be visible.
Edit: You'll notice that when returning to the menu, tapping the screen seems to mess up the moving bar in the background, despite the gameBarMovement timer being invalidated upon moving from the game to the menu. The fact that they're using separate class files also should mean the bars shouldn't be effected? Knowing me, I've missed something fairly obvious.
This is how the UIViewController life-cycle works as far as I know. UIViewcontrollers aren't unloaded until the app starts running out of memory. What you probably need is some way, in your game VC, to stop the game loop from running and resume it once a new game is started.

How to effectively pause a game in spritekit?

This seems like such a basic concept but there is really no good answer.
I currently have a pretty basic setup, in my game's scene, I have an enum gameState which is currently either inGame or gamePaused.
I have my button set up, and I have it so pressing simply toggles gameState.
Then, to make it work, I have two separate update methods: One for when gamePaused, one for when inGame.
This works for 95% of my game, as the updates in my game can be pretty readily started and stopped without any issues. There are some issues I cannot tackle though.
First and foremost are actions. I use SKActions for a bit of my project (some movement, scaling, fading...) and this method does NOT pause them. This can be catastrophic in certain points. Secondly, this doesn't handle particles, physics, and a few other things that are not directly associated to my update methods.
The only clue I have is self.view.paused = YES, but that isn't going to work either.
First off, this DOES fix my actions, particles, and physics problem... kinda. But This question suggests that SKActions aren't actually PAUSED by this, but actually STOPPED completely. Is this true? If it is, then it won't work smoothly either because my actions are thrown out of whack.
Also, pausing the view seems to do what it says: stop everything. EVERYTHING. Newbie question here, but how am I supposed to get any code to run at that point? It's all cut off. Is this where I need subViews? I have never used a subView yet, but it sounds like its what I want in this case.
Simply put, there are a lot of unanswered questions for me, and I don't know how to proceed. I'm hoping there's some 'standard procedure' for pausing in Sprite Kit, but with pausing the view halting actions I truly have no idea where to proceed.
Should I move away from using actions? Is my idea of a pause subView sound?
I don't want to babble, all I want to know is how you go about pausing in your average Sprite Kit project. Additional info provided upon request.
Pausing a node will pause (not stop) the node's actions, and i suppose pause will also be applied to all children of the paused node in the same way. All other unpaused nodes will continue to run their actions to completion.
You should have a "game layer" node with all game nodes in them that you want to pause, and then just pause that "game layer" node. Then have a "pause game menu" node where you add all the pause menu stuff you need which will continue to function normally even if the game layer is paused.
Be very sure you do not use performSelector or NSTimer or GCD or any other scheduling methods besides actions or the scene's update: method because those will not adhere to a node's paused state.
Pausing the view effectively freezes everything in it, pausing the scene according to some will not pause the update: calls - but I have not verified this myself. If this were the case you can always check inside the update method whether a given node that you send a message to is paused and if so, decide not to send certain messages to that node.
I just called a map function on all children of the scene and set the paused property to true
self.children.map{($0 as SKNode).paused = false}
By setting it to true you can easily undo the freeze.
EDIT:
Better use a for-loop to iterate over the children.
for node in self.children as [SKNode] {
node.paused = false
}
I can tell you what I did in my game:
Pause the SKView on -applicationWillResignActive: (or equivalent, using NSNotifications),
Un-pause the SKView on -applicationDidBecomeActive: (or equivalent, using NSNotifications),
For the actual game scene only, I set a boolean flag _isPaused when resigning active, and if it is true I just skip the -update: method (frame updates). (I also show the "paused" menu when the user resumes the app).
...But my game is a simple puzzle game, and there's no long actions that should continue past the pause/resume. I can not confirm right now that all actions are aborted, but I think it's not the case.
I also used self.children.map{($0 as SKNode).paused = false} and it does work if you create a var layer of type SKSpriteNode and add it on top of the scene. But I also have an NSTimer I'm using to spawn sprites on the scene. Everything currently on the scene is paused, but sprites keep appearing and moving across the screen. It is not pausing the spawning.
I tried pausing the NSTimer when I call the above code by setting repeats to false, then setting it to true when I remove the layer but it doesn't work. I also tried self.scene?.view?.paused = true but that freezes everything and the layer I create does not even appear onscreen.
You need to set the delegate for the View!
func PauseGame(){
self.scene.view.paused = true
}
fun playGame(){
self.scene.pause = false
}
This function is work perfectly if you are not using the NSTimer to call a function. If you use NSTimer your view will pause perfectly but when you play the game again by play game functionality you see that all the functions that use the NSTimer function that runs in the back end and your screen full with your sprite-kits. So when you use NSTimer in the function you have to first pause the NSTimer functions also after that this function work perfectly.
//For Pause
func pauseGame() {
scene?.view?.paused = true
}
//For play.
func playGame() {
scene?.view?.paused = false
}

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