Move SKSpriteNode position across multiple scenes - ios

Question

I have two scenes with scenery where clouds (SKSpriteNodes) move on the x-axis. When I change scenes they reset to their initial position.
How can I pass the x-position to the new scene when I move scenes?
This is my code. Both scenes have the same code and structure.
Thanks, guys!
override func didMoveToView(view: SKView) {
addScene()
addMenuButtons()
addSocial()
}
override func update(currentTime: CFTimeInterval) {
if self.cloud01.position.x < self.cloud01.size.width * -1 {
self.cloud01.position.x = self.frame.size.width + (self.cloud01.size.width / 2)
} else {
self.cloud01.position.x -= 0.5
}
if self.cloud02.position.x < self.cloud02.size.width * -1 {
self.cloud02.position.x = self.frame.size.width + (self.cloud02.size.width / 2)
} else {
self.cloud02.position.x -= 0.3
}
if self.cloud03.position.x < self.cloud03.size.width * -1 {
self.cloud03.position.x = self.frame.size.width + (self.cloud03.size.width / 2)
} else {
self.cloud03.position.x -= 0.4
}
}
func addScene() {
self.cloud01.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud01.size.width = self.frame.size.width / 3
self.cloud01.size.height = self.cloud01.size.width / 5
self.cloud01.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMaxY(self.frame) - 50)
self.cloud02.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud02.size.width = self.frame.size.width / 3
self.cloud02.size.height = self.cloud01.size.width / 5
self.cloud02.position = CGPointMake(CGRectGetMaxX(self.frame) - 50, CGRectGetMaxY(self.frame) - 200)
self.cloud03.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud03.size.width = self.frame.size.width / 3
self.cloud03.size.height = self.cloud01.size.width / 5
self.cloud03.position = CGPointMake(CGRectGetMinX(self.frame) + 50, CGRectGetMaxY(self.frame) - 125)
self.addChild(self.cloud01)
self.addChild(self.cloud02)
self.addChild(self.cloud03)
}

Answer 1

When you press Button from first Scene you can store cloud's positions into NSUserDefaults this way into touchBegan method:
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
/* Called when a touch begins */
for touch in (touches as! Set<UITouch>) {
let location = touch.locationInNode(self)
if self.nodeAtPoint(location) == self.playButton {
let cloud1Pos = cloud01.position
let cloud2Pos = cloud02.position
let cloud3Pos = cloud03.position
NSUserDefaults().setObject(NSStringFromCGPoint(cloud1Pos), forKey: "cloud1Pos")
NSUserDefaults().setObject(NSStringFromCGPoint(cloud2Pos), forKey: "cloud2Pos")
NSUserDefaults().setObject(NSStringFromCGPoint(cloud3Pos), forKey: "cloud3Pos")
let reveal = SKTransition.flipHorizontalWithDuration(0.5)
let letsPlay = playScene(size: self.size)
self.view?.presentScene(letsPlay, transition: reveal)
}
}
}
After that when new scene is load into view the you can read stored values:
let cloud1Pos = CGPointFromString(NSUserDefaults().objectForKey("cloud1Pos") as! String)
let cloud2Pos = CGPointFromString(NSUserDefaults().objectForKey("cloud2Pos") as! String)
let cloud3Pos = CGPointFromString(NSUserDefaults().objectForKey("cloud3Pos") as! String)
Now you have all cloud's position so you can assign that position to your cloud:
func addScene() {
self.cloud01.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud01.size.width = self.frame.size.width / 3
self.cloud01.size.height = self.cloud01.size.width / 5
self.cloud01.position = cloud1Pos
self.cloud02.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud02.size.width = self.frame.size.width / 3
self.cloud02.size.height = self.cloud01.size.width / 5
self.cloud02.position = cloud2Pos
self.cloud03.anchorPoint = CGPointMake(0.5, 0.5)
self.cloud03.size.width = self.frame.size.width / 3
self.cloud03.size.height = self.cloud01.size.width / 5
self.cloud03.position = cloud3Pos
self.addChild(self.cloud01)
self.addChild(self.cloud02)
self.addChild(self.cloud03)
}
And One suggestion for you. Don't update cloud position from Update method instead of that you can make one function like updatePosOfCloud and you can run that function into didMoveToView method this way:
runAction(SKAction.repeatActionForever(SKAction.sequence([SKAction.runBlock(updatePosOfCloud), SKAction.waitForDuration(0.05)])))
I have did this in my sample project.
HERE is complete working project.
EDIT:
As Paulw11 suggested you can do it this way too:
declare global variables above the class declaration of your first scene:
var cloud1Position : CGPoint?
var cloud2Position : CGPoint?
var cloud3Position : CGPoint?
This can store your clouds position and when button is pressed you can assign the position of clouds to this variables this way:
cloud1Position = cloud01.position
cloud2Position = cloud02.position
cloud3Position = cloud03.position
In your second scene you can assign position to clouds:
self.cloud01.position = cloud1Position!
self.cloud02.position = cloud2Position!
self.cloud03.position = cloud3Position!
you can use any way to achieve your requirement.