I'm making a game using Sprite Kit and I want to be able to drag and drop boxes as they travel down the screen.
Here's the gist of the code: I spawn the boxes on a timer and they move down the screen.
override func didMoveToView(view: SKView) {
let timer = NSTimer.scheduledTimerWithTimeInterval(2.0, target: self, selector: Selector("spawnBox"), userInfo: nil, repeats: true)
}
func spawnBox() {
/* Set up the box */
addChild(box)
let boxMoveDown = SKAction.moveToY(-100, duration: 5.0)
let actionDone = SKAction.removeFromParent()
box.runAction(SKAction.sequence([boxMoveDown, actionDone]))
}
But the problem is I how can I move a specific child which I am touching without affecting all the other 'children'? I understand that at the moment, every time I spawn a box it's exactly the same so I can't be specific when I set a individual child's position.
Here's what's inside my touchesBegan and touchesMoved functions
if let touch = touches.first {
let location = touch.locationInNode(self)
let objects = nodesAtPoint(location) as [SKNode]
if objects.contains(nodeAtPoint(location)) && nodeAtPoint(location).name == "box" {
box.position = location
box.removeAllActions()
}
}
The - box.position = location is what
needs changing.
Hopefully you understand my idea. I've tried to keep included code to what's necessary. I'm quite new to Sprite Kit which you can probably tell.
If I were you, I would handle it this way:
Create a custom class for your box nodes that extends SKSpriteNode.
In this custom class, override the touch property.
Then set the position inside this function based on location.
Now all you need to worry about is your zPosition, whatever child has the highest zPosition will be the one that gets called on touch.
You do not need to worry about nodesAtPoint or what not anymore, the API will handle all that for you.
Related
I am making a word game. For this I am using SceneKit and adding a SpriteNodes to represent letter tiles.
The idea is that when a user clicks on a letter tile, some extra tiles appear around it with different letter options. My issue is regarding the touch gestures for various interactions.
When a user taps on a letter tile, additional tiles are shown. I have achieved this using the following method in my tile SpriteNode class:
override func touchesBegan(_ touches:Set<UITouch> , with event: UIEvent?) {
guard let touch = touches.first else {
return
}
delegate?.updateLetter(row: row, column: column, x:xcoord, y:ycoord, useCase: 1)
}
This triggers the delegate correctly which shows another sprite node.
What I would like to achieve is for a long press to remove the sprite node from parent. I have found the .removeFromParent() method, however I cannot get this to detect a long press gesture.
My understanding is that this type of gesture must be added using UIGestureRecognizer. I can add the following method to my Scene class:
override func didMove(to view: SKView) {
let longPress = UILongPressGestureRecognizer(target: self,
action: #selector(GameScene.longPress(sender:)))
view.addGestureRecognizer(longPress)
}
#objc func longPress(sender: UILongPressGestureRecognizer) {
print("Long Press")
This will detect a long press anywhere on the scene. However I need to be able to handle the pressed nodes properties before removing it. I have tried adding the below to the longPress function:
let location = sender.location(in: self)
let touchedNodes = nodes(at: location)
let firstTouchedNode = atPoint(location).name
touchedNodes[0].removeFromParent()
but I get the following error: Cannot convert value of type 'GameScene' to expected argument type 'UIView?'
This seems a little bit of a messy way of doing things, as I have touch methods in different places.
So my question is, how can I keep the current touchesBegan method that is in the tile class, and add a long press gesture to be able to reference and delete the spriteNode?
Long press gestures are continuous gestures that may be called multiple times as you are seeing. Have you tried Recognizer.State.began, .changed, .ended? I solved a similar problem doing things this way.
EDIT - I think one way to get there is to get your object on handleTap and hang on to the object. Then when LongPress happens, you already have your node. If something changes before longPress, obviously you need to reset. Sorry, this is some extra code on here, but look at hitTest.
#objc func handleTap(recognizer: UITapGestureRecognizer)
{
let location: CGPoint = recognizer.location(in: gameScene)
if(data.isAirStrikeModeOn == true)
{
let projectedPoint = gameScene.projectPoint(SCNVector3(0, 0, 0))
let scenePoint = gameScene.unprojectPoint(SCNVector3(location.x, location.y, CGFloat(projectedPoint.z)))
gameControl.airStrike(position: scenePoint)
}
else
{
let hitResults = gameScene.hitTest(location, options: hitTestOptions)
for vHit in hitResults
{
if(vHit.node.name?.prefix(5) == "Panel")
{
// May have selected an invalid panel or auto upgrade was on
if(gameControl.selectPanel(vPanel: vHit.node.name!) == false) { return }
return
}
}
}
}
So I am not completely satisfied with this answer, however it is a work around for what I need.
What I have done is added two variables ‘touchesStart’ and ‘touchesEnd’ to my tiles class.
Then in touchesBegan() I add a call to update touchesStart with CACurrentMediaTime() and update touchesEnd via the touchesEnded() function.
Then in the touchesEnded() I subtract touchesStart from touchesEnd. If the difference is more than 1.0 I call the function for long press. If less than 1.0 I call the function for tap.
I have reviewed countless references to try to understand why my scene is not behaving the way i expected it to, such as this.
Here is my very simple SKScene (2 child nodes):
The scene has a SpriteNode (which covers the entire scene as a background image). This has a zPosition = 0.
The scene has a 2nd node (SKNode) which itself has another child (up to 2 levels). This has a zPosiiton - 2.
ALL nodes have .userInteractionEnabled = false
Issue:
When i click anywhere all i see is that the 1st child (SpriteNode) is touched. The 2nd child (SKNode) is never touch-detected.
Note that the z-ordering of the Nodes are being rendered as I expect them. It is the touch-detection that doesnt appear to be working.
Snippet of my touchesBegan method:
for touch in touches {
let touchLocation = touch.locationInNode(self)
let sceneTouchPoint = self.convertPointToView(touchLocation)
let touchedNode = self.nodeAtPoint(sceneTouchPoint)
if (touchedNode.name != nil) {
print("Touched = \(touchedNode.name! as String)")
}
}
I had a similar issue (background in z: 999 + spawning "ducks" nodes in z: <999) that I solved with the following code in Swift 4:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch:UITouch = touches.first!
let positionInScene = touch.location(in: self)
let touchedNodes = self.nodes(at: positionInScene)
for touch in touchedNodes {
let touchName = touch.name
if (touchName != nil && touchName!.hasPrefix("pato_")) {
touch.removeFromParent()
}
}
}
I had several layers of nodes because I used a mask over my game with buttons to make selections and move forward. I had issues with the buttons not working until I made a "startState:Bool = true" and updated this to false when the start screen was clicked through. I then had each of my buttons on that start page to have && startState==true for there clicks to be taken. It may be that your clicks are being recorded - but its not the node you think you are using. I would put print("NodeXXX") on each entry in touches and give it a unique name so you can see where the touches are actually happening.
Hope that helps.
Best regards,
mpe
I have less than 1 year using SpriteKit so I didn't use SKNodes as layers before until recently.
I have an SKNode layer that holds all of the fish and the user's position, for example:
var layerMainGame = SKNode()
layerMainGame.zPosition = 50
layerMainGame.addChild(userPosition)
layerMainGame.addChild(pipFish)
addChild(layerMainGame)
The interaction whether the user touched a fish or not is handled with this function, which is basically checking if their frames crossed:
if CGRectIntersectsRect(CGRectInset(node.frame, delta.dx, delta.dy), self.userPosition.frame) {
print("You got hit by \(name).")
gameOver()
}
It works. The interaction between the userPosition and pipFish works. What doesn't work is fish that are added as the game progresses. I have a function spawning different types of fish in intervals like this:
func spawnNew(fish: SKSpriteNode) {
layerMainGame.addChild(fish)
}
The interaction between the user and those fish that get added to the same layer later in the game does not work. I can pass right through them and no game over happens. When I completely remove the entire layerMainGame variable and just add them to the scene like normal, all the interactions work. Adding them all to the same SKNode layer doesn't work.
This is the function that creates a hit collision for every fish.
func createHitCollisionFor(name: String, GameOver gameOver: String!, delta: (dx: CGFloat, dy: CGFloat), index: Int = -1) {
enumerateChildNodesWithName(name) { [unowned me = self] node, _ in
if CGRectIntersectsRect(CGRectInset(node.frame, delta.dx, delta.dy), self.userPosition.frame) {
me.gameOverImage.texture = SKTexture(imageNamed: gameOver)
didGetHitActions()
me.runAction(audio.playSound(hit)!)
if index != -1 {
me.trophySet.encounterTrophy.didEncounter[index] = true
}
print("You got hit by \(name).")
}
}
}
And I call it like this:
createHitCollisionFor("GoldPiranha", GameOver: model.gameOverImage["Gold"], delta: (dx: 50, dy: 50), index: 1)
It works when the fish are not in the layer, but doesn't work when they are added to the layer.
When a node is placed in the node tree, its position property places it within a coordinate system provided by its parent.
Sprite Kit uses a coordinate orientation that starts from the bottom left corner of the screen (0, 0), and the x and y values increase as you move up and to the right.
For SKScene, the default value of the origin – anchorPoint is (0, 0), which corresponds to the lower-left corner of the view’s frame rectangle. To change it to center you can specify (0.5, 0.5)
For SKNode, the coordinate system origin is defined by its anchorPoint which by default is (0.5, 0.5) which is center of the node.
In your project you have layerMainGame added for example to the scene, his anchorPoint is by default (0.5,0.5) so the origin for the children like your fish is the center, you can see it if you change the fish positions like:
func spawnNew(fish: SKSpriteNode) {
layerMainGame.addChild(fish)
fish.position = CGPointZero // position 0,0 = parent center
}
Hope it help to understand how to solve your issue.
Update: (after your changes to the main question)
To help you better understand what happens I will give an example right away:
override func didMoveToView(view: SKView) {
var layerMainGame = SKNode()
addChild(layerMainGame)
let pipFish = SKSpriteNode(color: UIColor.yellowColor(), size: CGSizeMake(50,50))
pipFish.name = "son"
self.addChild(pipFish)
let layerPipFish = SKSpriteNode(color: UIColor.yellowColor(), size: CGSizeMake(50,50))
layerPipFish.name = "son"
layerMainGame.addChild(layerPipFish)
enumerateChildNodesWithName("son") { [unowned me = self] node, _ in
print(node)
}
}
Output:
Now I will simply change the line:
layerMainGame.addChild(layerPipFish)
with:
self.addChild(layerPipFish)
Output:
What happened?
As you can see enumerateChildNodesWithName written as your and my code print only childs directly added to self (because actually we launch enumerateChildNodesWithName which it is equal to launch self.enumerateChildNodesWithName )
How can I search in the full node tree?
If you have a node named "GoldPiranha" then you can search through all descendants by putting a // before the name. So you would search for "//GoldPiranha":
enumerateChildNodesWithName("//GoldPiranha") { [unowned me = self] ...
what I'm trying to achieve is that the Node would have the same shape as PhysicsBody/texture (fire has a complicated shape), and then I'm trying to make only fireImage touchable. So far when I'm touching outside of the fireImage on the screen and it still makes a sound. It seems that I'm touching the squared Node, but I want to touch only the sprite/texture.
Would appreciate your help.
The code is below:
import SpriteKit
import AVFoundation
private var backgroundMusicPlayer: AVAudioPlayer!
class GameScene2: SKScene {
var wait1 = SKAction.waitForDuration(1)
override func didMoveToView(view: SKView) {
setUpScenery()
}
private func setUpScenery() {
//I'm creating a Fire Object here and trying to set its Node a physicsBody/texture shape:
let fireLayerTexture = SKTexture(imageNamed: fireImage)
let fireLayer = SKSpriteNode(texture: fireLayerTexture)
fireLayer.anchorPoint = CGPointMake(1, 0)
fireLayer.position = CGPointMake(size.width, 0)
fireLayer.zPosition = Layer.Z4st
var firedown = SKAction.moveToY(-200, duration: 0)
var fireup1 = SKAction.moveToY(10, duration: 0.8)
var fireup2 = SKAction.moveToY(0, duration: 0.2)
fireLayer.physicsBody = SKPhysicsBody(texture: fireLayerTexture, size: fireLayer.texture!.size())
fireLayer.physicsBody!.affectedByGravity = false
fireLayer.name = "fireNode"
fireLayer.runAction(SKAction.sequence([firedown, wait1, fireup1, fireup2]))
addChild(fireLayer)
}
//Here, I'm calling a Node I want to touch. I assume that it has a shape of a PhysicsBody/texture:
override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {
for touch: AnyObject in touches {
let touch = touches.anyObject() as UITouch
let touchLocation = touch.locationInNode(self)
let node: SKNode = nodeAtPoint(touchLocation)
if node.name == "fireNode" {
var playguitar = SKAction.playSoundFileNamed("fire.wav", waitForCompletion: true)
node.runAction(playguitar)
}
}
}
}
Physics bodies and their shapes are for physics — that is, for simulating things like collisions between sprites in your scene.
Touch handling (i.e. nodeAtPoint) doesn't go through physics. That's probably the way it should be — if you had a sprite with a very small collision surface, you might not necessarily want it to be difficult to touch, and you also might want to be able to touch nodes that don't have physics. So your physics body doesn't affect the behavior of nodeAtPoint.
An API that lets you define a hit-testing area for a node — that's independent of the node's contents or physics — might not be a bad idea, but such a thing doesn't currently exist in SpriteKit. They do take feature requests, though.
In the meantime, fine-grained hit testing is something you'd have to do yourself. There are at least a couple of ways to do it:
If you can define the touch area as a path (CGPath or UIBezierPath/NSBezierPath), like you would for creating an SKShapeNode or a physics body using bodyWithPolygonFromPath:, you can hit-test against the path. See CGPathContainsPoint / containsPoint: / containsPoint: for the kind of path you're dealing with (and be sure to convert to the right local node coordinate space first).
If you want to hit-test against individual pixels... that'd be really slow, probably, but in theory the new SKMutableTexture class in iOS 8 / OX X v10.10 could help you. There's no saying you have to use the modifyPixelDataWithBlock: callback to actually change the texture data... you could use that once in setup to get your own copy of the texture data, then write your own hit testing code to decide what RGBA values count as a "hit".
I'm using SpriteKit (with Xcode 6 and Swift) and I have a character on the screen that I move around with on screen joysticks, and I want a little trail to follow behind him. How do I do that?
How big would my image need to be, and what would it need to look like?
Also what would I use in my code?
You should take a look at SKEmitterNode; it will "emit" particles that you can use as your trail. You can design the look and feel of your particles right in Xcode by adding a "SpriteKit Particle File" to your project:
You'd then load the particle file in to a new SKEmitterNode like so:
let emitter = SKEmitterNode(fileNamed: "CharacterParticle.sks")
Then you'll need to set the SKEmitterNode's targetNode property to your SKScene so that the particles it emits don't move with your character (i.e. they leave a trail):
emitter.targetNode = scene
Then add your emitter to your character's SKNode. Lets assume you have an SKNode for your character called character, in that case the code would simply be:
character.addChild(emitter)
Typically this sort of thing would be done in your scene's setup method (in Apple's SpriteKit template, it's usually in didMoveToView). It could also be done in your character's custom SKNode or SKSpriteNode class, if you have one. If you put it in didMoveToView, it would look something like:
override func didMoveToView(view: SKView) {
// ... any character or other node setup ...
let emitter = SKEmitterNode(fileNamed: "CharacterParticle.sks")
emitter.targetNode = self
character.addChild(emitter)
// ... any other setup ...
}
Although SKEmitterNode is a fine option. I would suggest you use a SKSpriteNode instead. The Emitters in Xcode cause a lot of lag when used frequent and in sequence.
The best way to create a trail in my opinion is by preloading a SKTexture when loading up the application. For this I would suggest creating a class like this.
class AssetsManager {
private init() {};
static let shared = AssetsManager();
func preloadAssets(with texture: SKTexture) {
texture.preload {
print("Sprites preloaded")
}
}
And than calling it as so in either your AppDelegate or MenuScene:
AssetsManager.shared.preloadAssets(with: SKTexture(imageNamed: "yourImage"))
Than for the "Creating a trail part":
Create a timer
var timer: Timer!
Start your timer
timer = Timer.scheduledTimer(timeInterval: interval, target: self, selector: #selector(ballTrail), userInfo: nil, repeats: true)
Create the ballTrail function
#objc func ballTrail() {
let trail = SKSpriteNode(texture: SKTexture(imageNamed: "your Image"))
trail.size = size
trail.position = player.position
trail.zPosition = player.positon - 0.1
addChild(trail)
trail.run(SKAction.scale(to: .zero, duration: seconds))
trail.run(SKAction.fadeOut(withDuration: seconds)
DispatchQueue.main.asyncAfter(deadline: .now() + seconds) {
trail.removeFromParent()
}
}
You can fiddle around with the actions and timings you would like to use. Hopefully this will help someone!