Currently I have a Swift/Spritekit app that drops a sprite from the sky, they have collisions off so they can fall through the floor, however I am trying to make a statement that will detect when the player sprite touches the sprite falling from the sky then deletes that child and adds a point to the score var.
Update: 04/29/18 2:10 CST
As of now this is what I have
import SpriteKit
import GameplayKit
class GameScene: SKScene, SKPhysicsContactDelegate {
var activePlayer:SKSpriteNode! = SKSpriteNode() //Sets active character
var bg:SKSpriteNode! = SKSpriteNode()
var bananaCollected = 0 //Defines banana var
var timer: Timer?
let bananaCat : UInt32 = 0x1 << 1
let playerCat : UInt32 = 0x1 << 2
func bananaDrop() { //Defines bananaDrop
let banana = SKSpriteNode(imageNamed:"banana")
//print("- Debug: [bananaDrop] successfully initiated -")
banana.name = "banana"
//Size of banana
banana.xScale = 0.25
banana.yScale = 0.25
//Defines physics properties
let physicsBody = SKPhysicsBody(circleOfRadius: 15)
//let physicsBody = SKPhysicsBody()
//physicsBody.pinned = true //Suspend in air
physicsBody.allowsRotation = false
physicsBody.affectedByGravity = true
//physicsBody.collisionBitMask = 0
banana.physicsBody?.categoryBitMask = bananaCat
banana.physicsBody?.collisionBitMask = 0
banana.physicsBody?.contactTestBitMask = playerCat
//categoryBitMask is what the physics category of the object is
//banana.physicsBody!.categoryBitMask = playerCategory
//collisionBitMask is what the physics category of objects that this cannot pass through are...multiple categories would be typed like... `cat1 | cat2`
//banana.physicsBody!.collisionBitMask = 0
//contactTestBitMask is what the physics category of the objects that we get alerted to upon contact
//activePlayer.physicsBody!.contactTestBitMask = obstacleCategory
banana.physicsBody = physicsBody
//Starting Location Defined
var x: CGFloat = 0 //Defines X
let y: CGFloat = 400 //Defines how high up banana drops
let bananaDrop = GKShuffledDistribution(lowestValue: 1, highestValue: 11)
//Drop locations defined (relation to X)
switch bananaDrop.nextInt() {
case 1:
x = -170
case 2:
x = -160
case 3:
x = -120
case 4:
x = -80
case 5:
x = -40
case 6:
x = 0
case 7:
x = 40
case 8:
x = 80
case 9:
x = 120
case 10:
x = 160
case 11:
x = 170
default:
fatalError("Case num outside range")
}
banana.position = CGPoint(x: x, y: y)
//Adds banana
self.addChild(banana)
}
func bDropF() { //Defintes Banana Drop Final
Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: { [weak self] timer in
self?.timer = timer
self?.timerTime()
})
}
//Stop droping bananas
deinit {
self.timer?.invalidate()
}
func timerTime() {
bananaDrop()
}
override func didMove(to view: SKView) {
print("- Debug: Game Scene Loaded -")
bDropF() //Calls banana drop
if let setupBG:SKSpriteNode = self.childNode(withName: "bg") as? SKSpriteNode {
bg = setupBG
bg.name = "bg"
bg.physicsBody?.affectedByGravity = false
bg.zPosition = -1
}
func didBeginContact(_ contact: SKPhysicsContact){ //Banana Collect
if let firstNode = contact.bodyA.node as? SKSpriteNode, let secondNode = contact.bodyB.node as? SKSpriteNode {
let object1: String = firstNode.name!
let object2: String = secondNode.name!
if (object1 == "player") || (object2 == "banana") {
print("colliding!")
}
}
}
//Player Definitions
if let randoPlayer:SKSpriteNode = self.childNode(withName: "player") as? SKSpriteNode { //Test for Char type
activePlayer = randoPlayer //Char Set
activePlayer.physicsBody?.isDynamic = true //Set dynamic
activePlayer.physicsBody?.affectedByGravity = true //Set dynamic gravity
activePlayer.name = "player"
print("Player Initiated")
print("Physics set :: Dynamic(true):AffectedByGravity(true)")
} else {
print("Failed to initiate player")
}
}
func moveActivePlayerR() {//Right Touch Player Movements Defined
let walkAnimation:SKAction = SKAction(named: "WalkRight")!
let moveAction:SKAction = SKAction.moveBy(x: 100, y: 0, duration: 0.5) //Move Right Side
//let moveRight:SKAction = SKAction.group([walkAnimation, moveAction]) //Depricated
let sound = SKAction.playSoundFileNamed("walk.wav", waitForCompletion: false)
let finalWalkR:SKAction = SKAction.group([walkAnimation, moveAction, sound])
activePlayer.run(finalWalkR)
}
func moveActivePlayerL() { //Left Touch Player Movements Defined
let walkAnimation:SKAction = SKAction(named: "WalkLeft")!
let moveAction:SKAction = SKAction.moveBy(x: -100, y: 0, duration: 0.5) //Move Left Side
//let moveRight:SKAction = SKAction.group([walkAnimation, moveAction]) //Depricated
let sound = SKAction.playSoundFileNamed("walk.wav", waitForCompletion: false)
let finalWalkL:SKAction = SKAction.group([moveAction, sound, walkAnimation])
activePlayer.run(finalWalkL)
}
func touchDown(atPoint pos : CGPoint) {
print("touch \( pos.x),\(pos.y)") //Debug print
if(pos.x > 0) { //if touched right side of screen
print("Right touch")
moveActivePlayerR()
} else if (pos.x < 0) { //if touched left side of screen
print("Left touch")
moveActivePlayerL()
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
for t in touches {
self.touchDown(atPoint: t.location(in: self))
}
}
}
However even with these categories setup it still appears that I am unable to get them to collide properly. When they touch each other there is nothing in my console indicating that they have collided. Please help!
You do not have to have a collisionBitMask set in order to detect contact, you just need to set the contactTestBitMask to the category of the obstacle you want to detect the collision with. You then check for the collision in the didBegin func. Ensure that you have the SKPhysicsContactDelegate set on your scene.
class GameScene: SKScene, SKPhysicsContactDelegate
self.physicsWorld.contactDelegate = self
when setting up your objects
//categoryBitMask is what the physics category of the object is
object.physicsBody!.categoryBitMask = playerCategory
//collisionBitMask is what the physics category of objects that this cannot pass through are...multiple categories would be typed like... `cat1 | cat2`
object.physicsBody!.collisionBitMask = 0
//contactTestBitMask is what the physics category of the objects that we get alerted to upon contact
object.physicsBody!.contactTestBitMask = obstacleCategory
the didBegin func in your scene
func didBeginContact(_ contact: SKPhysicsContact) {
if let firstNode = contact.bodyA.node as? SKSpriteNode, let secondNode = contact.bodyB.node as? SKSpriteNode {
let object1: String = firstNode.name!
let object2: String = secondNode.name!
if (object1 == "obstacle") || (object2 == "obstacle") {
//run some code because these 2 have collided
}
}
}
...or...
func didBeginContact(_ contact: SKPhysicsContact) {
if contact.bodyA.categoryBitMask == PhysicsCategory.obstacleCategory || contact.bodyB.categoryBitMask == PhysicsCategory.obstacleCategory {
//obstacle has hit player do something
}
}
I am trying to make a simple game: Space ship on the bottom of the screen shooting asteroids "falling" from the top of the screen.
I am learning ECS and GameplayKit, and have been trying to turn shields into a component. I've heavily relied on Apple's DemoBots sample app, and have lifted the PhysicsComponent, ColliderType, and ContactNotifiableType from the sample code.
A shield needs to render the assets assoicated with it (one for full shields and one for half shields), a different physics body from the ship because it's radius is noticeably larger than the ship, and to keep track of it's state. To do this I wrote:
final class ShieldComponent: GKComponent {
enum ShieldLevel: Int {
case full = 0, half, none
}
var currentShieldLevel: ShieldLevel = .full {
didSet {
switch currentShieldLevel {
case .full:
node.isHidden = false
node.texture = SKTexture(image: #imageLiteral(resourceName: "shield"))
case .half:
node.isHidden = false
node.texture = SKTexture(image: #imageLiteral(resourceName: "damagedShield"))
case .none:
node.isHidden = true
}
}
}
let node: SKSpriteNode
override init() {
node = SKSpriteNode(imageNamed: "shield")
super.init()
node.physicsBody = {
let physicsBody = SKPhysicsBody(circleOfRadius: node.frame.size.width / 2)
physicsBody.pinned = true
physicsBody.allowsRotation = false
physicsBody.affectedByGravity = false
ColliderType.definedCollisions[.shield] = [
.obstacle,
.powerUp
]
physicsBody.categoryBitMask = ColliderType.shield.rawValue
physicsBody.contactTestBitMask = ColliderType.obstacle.rawValue
physicsBody.collisionBitMask = ColliderType.obstacle.rawValue
return physicsBody
}()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func loseShields() {
if let newShieldLevel = ShieldLevel(rawValue: self.currentShieldLevel.rawValue + 1) {
self.currentShieldLevel = newShieldLevel
}
}
func restoreShields() {
self.currentShieldLevel = .full
}
}
And in my Ship initializer I do this:
let shieldComponent = ShieldComponent()
renderComponent.node.addChild(shieldComponent.node)
It would great if I could reuse the RenderComponent, and PhysicsComponent from DemoBots have I have with my ship and asteroid GKEntity subclasses, but components cannot have components. I had made ShieldComponent a ContactNotifiableType, but because the shield node does not actually belong to the ship entity.
I know I'm clearly coming at this wrong, and I'm at a loss of how to correct this. I'm hoping to get an example of how to make a shield component.
You must understand that components are meant to handle only one behaviour. so git rid of the physics code in your init() function and instead Build a Physics component similar to the one in DemoBots.
Tweak Your render Component to your liking. The problem with using DemoBots code is that its not perfectly Suited. So lets tweak it
class RenderComponent: GKComponent {
// MARK: Properties
// The `RenderComponent` vends a node allowing an entity to be rendered in a scene.
#objc let node = SKNode()
var sprite = SKSpriteNode
// init
init(imageNamed name: String) {
self.sprite = SKSpriteNode(imageNamed: name)
}
// MARK: GKComponent
override func didAddToEntity() {
node.entity = entity
}
override func willRemoveFromEntity() {
node.entity = nil
}
}
final class ShieldComponent: GKComponent {
var node : SKSpriteNode
//add reference to ship entity
weak var ship: Ship?
enum ShieldLevel: Int {
case full = 0, half, none
}
var currentShieldLevel: ShieldLevel = .full {
didSet {
switch currentShieldLevel {
case .full:
node.isHidden = false
node.texture = SKTexture(image: #imageLiteral(resourceName: "shield"))
case .half:
node.isHidden = false
node.texture = SKTexture(image: #imageLiteral(resourceName: "damagedShield"))
case .none:
node.isHidden = true
}
}
}
// Grab the visual component from the entity. Unwrap it with a Guard. If the Entity doesnt have the component you get an error.
var visualComponentRef : RenderComponent {
guard let renderComponent = ship?.component(ofType: RenderComponent.self) else {
fatalError("entity must have a render component")
}
}
override init(shipEntity ship: Ship) {
let visualComponent = RenderComponent(imageNamed: "imageName")
node = visualComponent.sprite
self.ship = ship
super.init()
// get rid of this. Use a Physics Component for this, Kep your components to one behaviour only. Make them as dumb as possible.
// node.physicsBody = {
// let physicsBody = SKPhysicsBody(circleOfRadius: node.frame.size.width / 2)
// physicsBody.pinned = true
// physicsBody.allowsRotation = false
// physicsBody.affectedByGravity = false
//
// ColliderType.definedCollisions[.shield] = [
// .obstacle,
// .powerUp
// ]
//
// physicsBody.categoryBitMask = ColliderType.shield.rawValue
// physicsBody.contactTestBitMask = ColliderType.obstacle.rawValue
// physicsBody.collisionBitMask = ColliderType.obstacle.rawValue
// return physicsBody
// }()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func loseShields() {
if let newShieldLevel = ShieldLevel(rawValue: self.currentShieldLevel.rawValue + 1) {
self.currentShieldLevel = newShieldLevel
}
}
func restoreShields() {
self.currentShieldLevel = .full
}
};
Make sure to look at how I changed my components interaction with the entity. You can create a reference Object to Ship Entity Directly. Or you can check weather or not the ShieldComponent has an entity with the entity? property. (beware. it is an optional, so unwrap it.
Once you have the Entity reference you can then search it for other Components and retrieve The using component(ofType:_) property.
eg ship?.component(ofType: RenderComponent.self)
Other than this, I think you have a decent shield component
Any idea how I could implement a shop in my spriteKit game that users could buy different players with coins they have earned in game? any tutorials out there?
This is a multi-step project that took me about 500 loc (more without using .SKS) Here is the link to github finished project: https://github.com/fluidityt/ShopScene
Note, I am using a macOS SpriteKit project because it launches much faster on my computer. Simply change mouseDown() to touchesBegan() to get this to run on iOS.
First edit your GameScene.sks to look like this: (saves a bunch of time coding labels)
Make sure that you name everything EXACTLY as we need this to detect touch:
"entershop", "getcoins", "coinlabel", "levellabel"
This is the main "gameplay" scene and as you click coins++ you get levels and can move around. Clicking the shop will enter the shop.
Here is our GameScene.swift which matches this SKS:
import SpriteKit
class GameScene: SKScene {
let player = Player(costume: Costume.defaultCostume)
lazy var enterNode: SKLabelNode = { return (self.childNode(withName: "entershop") as! SKLabelNode) }()
lazy var coinNode: SKLabelNode = { return (self.childNode(withName: "getcoins" ) as! SKLabelNode) }()
lazy var coinLabel: SKLabelNode = { return (self.childNode(withName: "coinlabel") as! SKLabelNode) }()
lazy var levelLabel: SKLabelNode = { return (self.childNode(withName: "levellabel") as! SKLabelNode) }()
override func didMove(to view: SKView) {
player.name = "player"
if player.scene == nil { addChild(player) }
}
override func mouseDown(with event: NSEvent) {
let location = event.location(in: self)
if let name = atPoint(location).name {
switch name {
case "entershop": view!.presentScene(ShopScene(previousGameScene: self))
case "getcoins": player.getCoins(1)
default: ()
}
}
else {
player.run(.move(to: location, duration: 1))
}
}
override func update(_ currentTime: TimeInterval) {
func levelUp(_ level: Int) {
player.levelsCompleted = level
levelLabel.text = "Level: \(player.levelsCompleted)"
}
switch player.coins {
case 10: levelUp(2)
case 20: levelUp(3)
case 30: levelUp(4)
default: ()
}
}
};
Here you can see that we have a few other things going on not yet introduced: Player and Costume
Player is a spritenode subclass (it doubles as a data model and a UI element). Our player is just a colored square that gets moved around when you click the screen
The player wears something of Costume type, which is just a model that keeps track of data such as price, name, and the texture for the player to display.
Here is Costume.swift:
import SpriteKit
/// This is just a test method should be deleted when you have actual texture assets:
private func makeTestTexture() -> (SKTexture, SKTexture, SKTexture, SKTexture) {
func texit(_ sprite: SKSpriteNode) -> SKTexture { return SKView().texture(from: sprite)! }
let size = CGSize(width: 50, height: 50)
return (
texit(SKSpriteNode(color: .gray, size: size)),
texit(SKSpriteNode(color: .red, size: size)),
texit(SKSpriteNode(color: .blue, size: size)),
texit(SKSpriteNode(color: .green, size: size))
)
}
/// The items that are for sale in our shop:
struct Costume {
static var allCostumes: [Costume] = []
let name: String
let texture: SKTexture
let price: Int
init(name: String, texture: SKTexture, price: Int) { self.name = name; self.texture = texture; self.price = price
// This init simply adds all costumes to a master list for easy sorting later on.
Costume.allCostumes.append(self)
}
private static let (tex1, tex2, tex3, tex4) = makeTestTexture() // Just a test needed to be deleted when you have actual assets.
static let list = (
// Hard-code any new costumes you create here (this is a "master list" of costumes)
// (make sure all of your costumes have a unique name, or the program will not work properly)
gray: Costume(name: "Gray Shirt", texture: tex1 /*SKTexture(imageNamed: "grayshirt")*/, price: 0),
red: Costume(name: "Red Shirt", texture: tex2 /*SKTexture(imageNamed: "redshirt")*/, price: 5),
blue: Costume(name: "Blue Shirt", texture: tex3 /*SKTexture(imageNamed: "blueshirt")*/, price: 25),
green: Costume(name: "Green Shirt", texture: tex4 /*SKTexture(imageNamed: "greenshirt")*/, price: 50)
)
static let defaultCostume = list.gray
};
func == (lhs: Costume, rhs: Costume) -> Bool {
// The reason why you need unique names:
if lhs.name == rhs.name { return true }
else { return false }
}
The design of this struct is twofold.. first is to be a blueprint for a Costume object (which holds the name, price, and texture of a costume), and second it serves as a repository for all of your costumes via a hard-coded static master list property.
The function at the top makeTestTextures() is just an example for this project. I did this just so that way you can copy and paste instead of having to download image files to use.
Here is the Player.swift, which can wear the costumes in the list:
final class Player: SKSpriteNode {
var coins = 0
var costume: Costume
var levelsCompleted = 0
var ownedCostumes: [Costume] = [Costume.list.gray] // FIXME: This should be a Set, but too lazy to do Hashable.
init(costume: Costume) {
self.costume = costume
super.init(texture: costume.texture, color: .clear, size: costume.texture.size())
}
func getCoins(_ amount: Int) {
guard let scene = self.scene as? GameScene else { // This is very specific code just for this example.
fatalError("only call this func after scene has been set up")
}
coins += amount
scene.coinLabel.text = "Coins: \(coins)"
}
func loseCoins(_ amount: Int) {
guard let scene = self.scene as? GameScene else { // This is very specific code just for this example.
fatalError("only call this func after scene has been set up")
}
coins -= amount
scene.coinLabel.text = "Coins: \(coins)"
}
func hasCostume(_ costume: Costume) -> Bool {
if ownedCostumes.contains(where: {$0.name == costume.name}) { return true }
else { return false }
}
func getCostume(_ costume: Costume) {
if hasCostume(costume) { fatalError("trying to get costume already owned") }
else { ownedCostumes.append(costume) }
}
func wearCostume(_ costume: Costume) {
guard hasCostume(costume) else { fatalError("trying to wear a costume you don't own") }
self.costume = costume
self.texture = costume.texture
}
required init?(coder aDecoder: NSCoder) { fatalError() }
};
Player has a lot of functions, but they all could be handled elsewhere in the code. I just went for this design decision, but don't feel like you need to load up your classes with 2 line methods.
Now we are getting to the more nitty-gritty stuff, since we have set up our:
Base scene
Costume list
Player object
The last two things we really need are:
1. A shop model to keep track of inventory
2. A shop scene to display inventory, UI elements, and handle the logic of whether or not you can buy items
Here is Shop.swift:
/// Our model class to be used inside of our ShopScene:
final class Shop {
weak private(set) var scene: ShopScene! // The scene in which this shop will be called from.
var player: Player { return scene.player }
var availableCostumes: [Costume] = [Costume.list.red, Costume.list.blue] // (The green shirt wont become available until the player has cleared 2 levels).
// var soldCostumes: [Costume] = [Costume.defaultCostume] // Implement something with this if you want to exclude previously bought items from the store.
func canSellCostume(_ costume: Costume) -> Bool {
if player.coins < costume.price { return false }
else if player.hasCostume(costume) { return false }
else if player.costume == costume { return false }
else { return true }
}
/// Only call this after checking canBuyCostume(), or you likely will have errors:
func sellCostume(_ costume: Costume) {
player.loseCoins(costume.price)
player.getCostume(costume)
player.wearCostume(costume)
}
func newCostumeBecomesAvailable(_ costume: Costume) {
if availableCostumes.contains(where: {$0.name == costume.name}) /*|| soldCostumes.contains(costume)*/ {
fatalError("trying to add a costume that is already available (or sold!)")
}
else { availableCostumes.append(costume) }
}
init(shopScene: ShopScene) {
self.scene = shopScene
}
deinit { print("shop: if you don't see this message when exiting shop then you have a retain cycle") }
};
The idea was to have the fourth costume only be available at a certain level, but I've run out of time to implement this feature, but most of the supporting methods are there (you just need to implement the logic).
Also, Shop can pretty much just be a struct, but I feel that it's more flexible as a class for now.
Now, before jumping into ShopScene, our biggest file, let me tell you about a couple of design decisions.
First, I'm using node.name to handle touches / clicks. This lets me use the .SKS and the regular SKNode types quickly and easily. Normally, I like to subclass SKNodes and then override their own touchesBegan method to handle clicks. You can do it either way.
Now, in ShopScene you have buttons for "buy", "exit" which I have used as just regular SKLabelNodes; but for the actual nodes that display the costume, I have created a subclass called CostumeNode.
I made CostumeNode so that way it could handle nodes for displaying the costume's name, price, and doing some animations. CostumeNode is just a visual element (unlike Player).
Here is CostumeNode.swift:
/// Just a UI representation, does not manipulate any models.
final class CostumeNode: SKSpriteNode {
let costume: Costume
weak private(set) var player: Player!
private(set) var
backgroundNode = SKSpriteNode(),
nameNode = SKLabelNode(),
priceNode = SKLabelNode()
private func label(text: String, size: CGSize) -> SKLabelNode {
let label = SKLabelNode(text: text)
label.fontName = "Chalkduster"
// FIXME: deform label to fit size and offset
return label
}
init(costume: Costume, player: Player) {
func setupNodes(with size: CGSize) {
let circle = SKShapeNode(circleOfRadius: size.width)
circle.fillColor = .yellow
let bkg = SKSpriteNode(texture: SKView().texture(from: circle))
bkg.zPosition -= 1
let name = label(text: "\(costume.name)", size: size)
name.position.y = frame.maxY + name.frame.size.height
let price = label(text: "\(costume.price)", size: size)
price.position.y = frame.minY - price.frame.size.height
addChildrenBehind([bkg, name, price])
(backgroundNode, nameNode, priceNode) = (bkg, name, price)
}
self.player = player
self.costume = costume
let size = costume.texture.size()
super.init(texture: costume.texture, color: .clear, size: size)
name = costume.name // Name is needed for sorting and detecting touches.
setupNodes(with: size)
becomesUnselected()
}
private func setPriceText() { // Updates the color and text of price labels
func playerCanAfford() {
priceNode.text = "\(costume.price)"
priceNode.fontColor = .white
}
func playerCantAfford() {
priceNode.text = "\(costume.price)"
priceNode.fontColor = .red
}
func playerOwns() {
priceNode.text = ""
priceNode.fontColor = .white
}
if player.hasCostume(self.costume) { playerOwns() }
else if player.coins < self.costume.price { playerCantAfford() }
else if player.coins >= self.costume.price { playerCanAfford() }
else { fatalError() }
}
func becomesSelected() { // For animation / sound purposes (could also just be handled by the ShopScene).
backgroundNode.run(.fadeAlpha(to: 0.75, duration: 0.25))
setPriceText()
// insert sound if desired.
}
func becomesUnselected() {
backgroundNode.run(.fadeAlpha(to: 0, duration: 0.10))
setPriceText()
// insert sound if desired.
}
required init?(coder aDecoder: NSCoder) { fatalError() }
deinit { print("costumenode: if you don't see this then you have a retain cycle") }
};
Finally we have ShopScene, which is the behemoth file. It handles the data and logic for not only showing UI elements, but also for updating the Shop and Player models.
import SpriteKit
// Helpers:
extension SKNode {
func addChildren(_ nodes: [SKNode]) { for node in nodes { addChild(node) } }
func addChildrenBehind(_ nodes: [SKNode]) { for node in nodes {
node.zPosition -= 2
addChild(node)
}
}
}
func halfHeight(_ node: SKNode) -> CGFloat { return node.frame.size.height/2 }
func halfWidth (_ node: SKNode) -> CGFloat { return node.frame.size.width/2 }
// MARK: -
/// The scene in which we can interact with our shop and player:
class ShopScene: SKScene {
lazy private(set) var shop: Shop = { return Shop(shopScene: self) }()
let previousGameScene: GameScene
var player: Player { return self.previousGameScene.player } // The player is actually still in the other scene, not this one.
private var costumeNodes = [CostumeNode]() // All costume textures will be node-ified here.
lazy private(set) var selectedNode: CostumeNode? = {
return self.costumeNodes.first!
}()
private let
buyNode = SKLabelNode(fontNamed: "Chalkduster"),
coinNode = SKLabelNode(fontNamed: "Chalkduster"),
exitNode = SKLabelNode(fontNamed: "Chalkduster")
// MARK: - Node setup:
private func setUpNodes() {
buyNode.text = "Buy Costume"
buyNode.name = "buynode"
buyNode.position.y = frame.minY + halfHeight(buyNode)
coinNode.text = "Coins: \(player.coins)"
coinNode.name = "coinnode"
coinNode.position = CGPoint(x: frame.minX + halfWidth(coinNode), y: frame.minY + halfHeight(coinNode))
exitNode.text = "Leave Shop"
exitNode.name = "exitnode"
exitNode.position.y = frame.maxY - buyNode.frame.height
setupCostumeNodes: do {
guard Costume.allCostumes.count > 1 else {
fatalError("must have at least two costumes (for while loop)")
}
for costume in Costume.allCostumes {
costumeNodes.append(CostumeNode(costume: costume, player: player))
}
guard costumeNodes.count == Costume.allCostumes.count else {
fatalError("duplicate nodes found, or nodes are missing")
}
let offset = CGFloat(150)
func findStartingPosition(offset: CGFloat, yPos: CGFloat) -> CGPoint { // Find the correct position to have all costumes centered on screen.
let
count = CGFloat(costumeNodes.count),
totalOffsets = (count - 1) * offset,
textureWidth = Costume.list.gray.texture.size().width, // All textures must be same width for centering to work.
totalWidth = (textureWidth * count) + totalOffsets
let measurementNode = SKShapeNode(rectOf: CGSize(width: totalWidth, height: 0))
return CGPoint(x: measurementNode.frame.minX + textureWidth/2, y: yPos)
}
costumeNodes.first!.position = findStartingPosition(offset: offset, yPos: self.frame.midY)
var counter = 1
let finalIndex = costumeNodes.count - 1
// Place nodes from left to right:
while counter <= finalIndex {
let thisNode = costumeNodes[counter]
let prevNode = costumeNodes[counter - 1]
thisNode.position.x = prevNode.frame.maxX + halfWidth(thisNode) + offset
counter += 1
}
}
addChildren(costumeNodes)
addChildren([buyNode, coinNode, exitNode])
}
// MARK: - Init:
init(previousGameScene: GameScene) {
self.previousGameScene = previousGameScene
super.init(size: previousGameScene.size)
}
required init?(coder aDecoder: NSCoder) { fatalError("init(coder:) has not been implemented")}
deinit { print("shopscene: if you don't see this message when exiting shop then you have a retain cycle") }
// MARK: - Game loop:
override func didMove(to view: SKView) {
anchorPoint = CGPoint(x: 0.5, y: 0.5)
setUpNodes()
select(costumeNodes.first!) // Default selection.
for node in costumeNodes {
if node.costume == player.costume { select(node) }
}
}
// MARK: - Touch / Click handling:
private func unselect(_ costumeNode: CostumeNode) {
selectedNode = nil
costumeNode.becomesUnselected()
}
private func select(_ costumeNode: CostumeNode) {
unselect(selectedNode!)
selectedNode = costumeNode
costumeNode.becomesSelected()
if player.hasCostume(costumeNode.costume) { // Wear selected costume if owned.
player.costume = costumeNode.costume
buyNode.text = "Bought Costume"
buyNode.alpha = 1
}
else if player.coins < costumeNode.costume.price { // Can't afford costume.
buyNode.text = "Buy Costume"
buyNode.alpha = 0.5
}
else { // Player can buy costume.
buyNode.text = "Buy Costume"
buyNode.alpha = 1
}
}
// I'm choosing to have the buttons activated by searching for name here. You can also
// subclass a node and have them do actions on their own when clicked.
override func mouseDown(with event: NSEvent) {
guard let selectedNode = selectedNode else { fatalError() }
let location = event.location(in: self)
let clickedNode = atPoint(location)
switch clickedNode {
// Clicked empty space:
case is ShopScene:
return
// Clicked Buy / Leave:
case is SKLabelNode:
if clickedNode.name == "exitnode" { view!.presentScene(previousGameScene) }
if clickedNode.name == "buynode" {
// guard let shop = shop else { fatalError("where did the shop go?") }
if shop.canSellCostume(selectedNode.costume) {
shop.sellCostume(selectedNode.costume)
coinNode.text = "Coins: \(player.coins)"
buyNode.text = "Bought"
}
}
// Clicked a costume:
case let clickedCostume as CostumeNode:
for node in costumeNodes {
if node.name == clickedCostume.name {
select(clickedCostume)
}
}
default: ()
}
}
};
There's a lot to digest here, but pretty much everything happens in mouseDown() (or touchesBegan for iOS). I had no need for update() or other every-frame methods.
So how did I make this? The first step was planning, and I knew there were several design decisions to make (which may not have been the best ones).
I knew that I needed a certain set of data for my player and shop inventory, and that those two things would also need UI elements.
I chose to combine the data + UI for Player by making it a Sprite subclass.
For the shop, I knew that the data and UI elements would be pretty intense, so I separated them (Shop.swift handling the inventory, Costume.swift being a blueprint, and CostumeNode.swift handling most of the UI)
Then, I needed to link the data to the UI elements, which meant that I needed a lot of logic, so I decided to make a whole new scene to handle logic pertaining just to entering and interacting with the shop (it handles some graphics stuff too).
This all works together like this:
Player has a costume and coins
GameScene is where you collect new coins (and levels)
ShopScene handles most of the logic for determining which UI elements to display, while CostumeNode has the functions for animating the UI.
ShopScene also provides the logic for updating the Player's texture (costume) and coins through Shop.
Shop just manages the player inventory, and has the data with which to populate more CostumeNodes
When you are done with the shop, your GameScene instance is immediately resumed where you left off prior to entering
So the question you may have is, "how do I use this in my game??"
Well, you aren't going to be able to just copy and paste it. A lot of refactoring will likely be needed. The takeaway here is to learn the basic system of the different types of data, logic, and actions that you will need to create, present, and interact with a shop.
Here is the github again:
https://github.com/fluidityt/ShopScene
I am having trouble trying to cast a ContactBody to a custom SKNode. The implementation looks like this:
case PhysicsCategory.player | PhysicsCategory.spring:
if contact.bodyA.categoryBitMask == PhysicsCategory.spring{
if let theSpring = contact.bodyA.node as? Spring
{
theSpring.printMsg()
}else{
print("can't cast bodyA to spring")
}
}else{
if let theSpring = contact.bodyB.node as? Spring
{
theSpring.printMsg()
}else{
print("can't cast bodyB to spring")
}
}
When contact is made between the player and the spring, I get the message "can't cast bodyA to spring." The spring class looks like this:
import SpriteKit
class Spring: SKNode {
var impulse: Int
var sprite: SKSpriteNode
var textureAtlas: SKTextureAtlas
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
init (launchSpeed: Int){
impulse = launchSpeed
textureAtlas = SKTextureAtlas(named: "NonTiledItems")
sprite = SKSpriteNode(texture: textureAtlas.textureNamed("spring01"))
sprite.physicsBody = SKPhysicsBody(rectangleOfSize: sprite.size)
sprite.physicsBody!.categoryBitMask = PhysicsCategory.spring // could we make this button?
sprite.physicsBody!.allowsRotation = false
sprite.physicsBody!.dynamic = false
sprite.physicsBody!.affectedByGravity = false
sprite.physicsBody!.friction = 0.6
sprite.physicsBody!.collisionBitMask = PhysicsCategory.player
super.init()
addChild(sprite)
}
func printMsg(){
print("contact Made")
}
}
I cannot figure out why the ContactBody will not cast to the Spring class since spring inherits from SKNode. If anyone has any advice, it would be greatly appreciated.
your physics body is attached to an SKSpriteNode, not the Spring. You need to remove the skspritenode reference, you need Spring to be a child of SKSpriteNode, and you need to write a convenience init like this:
convenience init (launchSpeed: Int)
{
self.SKSpriteNode(texture: SKTextureAtlas(named: "NonTiledItems").textureNamed("spring01"))
impulse = launchSpeed
self.physicsBody = SKPhysicsBody(rectangleOfSize: self.size)
self.physicsBody!.categoryBitMask = PhysicsCategory.spring // could we make this button?
self.physicsBody!.allowsRotation = false
self.physicsBody!.dynamic = false
self.physicsBody!.affectedByGravity = false
self.physicsBody!.friction = 0.6
self.physicsBody!.collisionBitMask = PhysicsCategory.player
}
I'm making a game in XCode using SpriteKit. The game has a player and different types of projectiles that he has to avoid. When the player collides with the projectiles, the score changes and the projectile disappears. However, when two projectiles collide, they kind of bounce away.
I want to make that every time two projectiles collide, they act like nothing happened and they keep going in their original path. What should I do?
*Note: This is not the whole code, it's just what matters.
import SpriteKit
struct Physics {
static let player : UInt32 = 1
static let missileOne : UInt32 = 2
static let missileTwo : UInt32 = 3
}
class GameScene: SKScene, SKPhysicsContactDelegate {
var player = SKSpriteNode(imageNamed: "p1.png")
override func didMoveToView(view: SKView) {
physicsWorld.contactDelegate = self
player.position = CGPointMake(self.size.width/2, self.size.height/5)
player.physicsBody = SKPhysicsBody(rectangleOfSize: player.size)
player.physicsBody?.affectedByGravity = false
player.physicsBody?.dynamic = false
player.physicsBody?.categoryBitMask = Physics.player
player.physicsBody?.collisionBitMask = Physics.missileOne
player.physicsBody?.collisionBitMask = Physics.missileTwo
var missileOneTimer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("SpawnMissileOne"), userInfo: nil, repeats: true)
var missileTwoTimer = NSTimer.scheduledTimerWithTimeInterval(1.2, target: self, selector: Selector("SpawnMissileTwo"), userInfo: nil, repeats: true)
self.addChild(player)
}
//When contact happens
func didBeginContact(contact: SKPhysicsContact) {
var firstBody : SKPhysicsBody = contact.bodyA
var secondBody : SKPhysicsBody = contact.bodyB
if ((firstBody.categoryBitMask == Physics.player) && (secondBody.categoryBitMask == Physics.missileOne)) {
CollisionWithMissileOne(firstBody.node as SKSpriteNode, missileOne: secondBody.node as SKSpriteNode)
} else if ((firstBody.categoryBitMask == Physics.player) && (secondBody.categoryBitMask == Physics.missileTwo)){
CollisionWithMissileTwo(firstBody.node as SKSpriteNode, missileTwo: secondBody.node as SKSpriteNode)
} else if ((firstBody.categoryBitMask == Physics.missileOne)&&(secondBody.categoryBitMask == Physics.missileTwo)) {
CollisionBetweenMissiles(firstBody.node as SKSpriteNode, missileTwo: secondBody.node as SKSpriteNode)
}
}
//For Player and MissileOne
func CollisionWithMissileOne(player: SKSpriteNode, missileOne: SKSpriteNode) {
missileOne.removeFromParent()
}
//For Player and MissileTwo
func CollisionWithMissileOne(player: SKSpriteNode, missileTwo: SKSpriteNode) {
missileTwo.removeFromParent()
}
//For MissileOne and MissileTwo
func CollisionBetweenMissiles(missileOne: SKSpriteNode, missileTwo: SKSpriteNode) {
???WHAT SHOULD I CODE HERE???
}
}
The confusion is that the collisionBitMask is used to define which physicsBodies that interacts in the physicsModel. What you really want is contactTestBitmask.
Also your Physics doesn't return proper values to use for a Bit Mask. As pure Ints they should be 1,2,4,8 etc.
Here is your code changed to something that (hopefully) works, I've commented changes wherever I've made them.
struct Physics {
static let player : UInt32 = 1
static let missileOne : UInt32 = 2
static let missileTwo : UInt32 = 4 // to work properly as bit masks
}
This change is necessary if you want to check for contact with more than one type of physicsBody.categoryBitMask. Check out the player.physicsBody?.contactTestBitMask = ... in didMoveToView:
override func didMoveToView(view: SKView) {
physicsWorld.contactDelegate = self
// All your existing player-stuff is fine until...
// contactTest, not collision but contact, also: use bitwise OR
player.physicsBody?.contactTestBitMask = Physics.missileOne | Physics.missileTwo
self.addChild(player)
// It is not recommended to use NSTimer for SpriteKit, use SKActions instead
let missileOneWait = SKAction.waitForDuration(1)
let callSpawnOneAction = SKAction.runBlock({ self.spawnMissileOne() })
let missileOneRepeat = SKAction.repeatActionForever(SKAction.sequence([missileOneWait, callSpawnOneAction]))
runAction(missileOneRepeat)
let missileTwoWait = SKAction.waitForDuration(1.2)
let callSpawnTwoAction = SKAction.runBlock({ self.spawnMissileTwo() })
let missileTwoRepeat = SKAction.repeatActionForever(SKAction.sequence([missileTwoWait, callSpawnTwoAction]))
runAction(missileTwoRepeat)
}
Pretty much rewritten didBeginContact to something I believe reads and scales a lot better:
func didBeginContact(contact: SKPhysicsContact) {
var firstBody = contact.bodyA
var secondBody = contact.bodyB
// Rewritten with dynamic variables
var playerNode : SKSpriteNode? {
if firstBody.categoryBitMask == Physics.player {
return firstBody.node as? SKSpriteNode
} else if secondBody.categoryBitMask == Physics.player {
return secondBody.node as? SKSpriteNode
}
return nil
}
// If you want to handle contact between missiles you need to split this
// into two different variables
var missileNode : SKSpriteNode? {
let bitmask1 = firstBody.categoryBitMask
let bitmask2 = secondBody.categoryBitMask
if bitmask1 == Physics.missileOne || bitmask1 == Physics.missileTwo {
return firstBody.node as? SKSpriteNode
} else if bitmask2 == Physics.missileOne || bitmask2 == Physics.missileTwo {
return secondBody.node as? SKSpriteNode
}
return nil
}
if playerNode != nil {
collisionBetweenPlayer(playerNode, missile: missileNode)
}
}
Then you'll only need one function for contact between missile and player:
func collisionBetweenPlayer(player: SKSpriteNode?, missile: SKSpriteNode?) {
missile?.removeFromParent()
}