我正试图找到一种方法，在加电时增加一个以上的子弹。此外，它只是在前4次加电时直接上升，但我希望它在达到5级时有一点角度。
有人可以帮助我使用我目前拥有的以下代码来实现吗？
import SpriteKit
import GameplayKit
class GameScene: SKScene, SKPhysicsContactDelegate {
var player: SKSpriteNode!
var scoreLabel: SKLabelNode!
var score: Int = 0 {
didSet {
scoreLabel.text = "Score: \(score)"
}
}
var gameTimer: Timer!
var possibleAliens = ["alien", "alien2", "alien3"]
//bitmask for alien and torpedo's physics body
let alienCategory:UInt32 = 0x1 << 1
let photonTorpedoCategory:UInt32 = 0x1 << 0
//lives
var livesArray:[SKSpriteNode]!
//powerUp
var powerUp: Int = 1
//didMove
override func didMove(to view: SKView) {
addLives()
starField = SKEmitterNode(fileNamed: "Starfield")
starField.position = CGPoint(x: 0, y: 1472)
starField.advanceSimulationTime(10)
self.addChild(starField)
starField.zPosition = -1
player = SKSpriteNode(imageNamed: "shuttle")
player.position = CGPoint(x: self.frame.size.width / 3.6, y: player.size.height / 2 + 20)
self.addChild(player)
//physicsWorld
self.physicsWorld.gravity = CGVector(dx: 0, dy: 0)
self.physicsWorld.contactDelegate = self
//score and scoreLabel
scoreLabel = SKLabelNode(text: "Score: 0")
scoreLabel.position = CGPoint(x: 80, y: self.frame.size.height - 60)
scoreLabel.fontName = "AmericanTypewriter-Bold"
scoreLabel.fontSize = 28
scoreLabel.fontColor = UIColor.white
score = 0
self.addChild(scoreLabel)
//create a timeInterval that can be changed depending on the difficulty
var timeInterval = 0.6
if UserDefaults.standard.bool(forKey: "hard"){
timeInterval = 0.2
}
//gameTimer
gameTimer = Timer.scheduledTimer(timeInterval: timeInterval, target: self, selector: #selector(addAlien), userInfo: nil, repeats: true)
//motion Manager initialization in didMove
motionManger.accelerometerUpdateInterval = 0.2
//creatingan acceleration data in didMove
motionManger.startAccelerometerUpdates(to: OperationQueue.current!) { (data: CMAccelerometerData?, error: Error?) in
if let accelerometerData = data{
let acceleration = accelerometerData.acceleration
self.xAcceleration = CGFloat(acceleration.x) * 0.75 + self.xAcceleration * 0.25
}
}
}
//func addLives
func addLives() {
//initialize livesArray from GameScene
livesArray = [SKSpriteNode]()
for live in 1 ... 3 {
let liveNode = SKSpriteNode(imageNamed: "shuttle")
liveNode.name = "live\(live)"
liveNode.position = CGPoint(x: self.frame.size.width - CGFloat((4-live)) * liveNode.size.width, y: self.frame.size.height - 60)
self.addChild(liveNode)
livesArray.append(liveNode)
}
}
//func addAlien
func addAlien() {
//using GK, pick possibleAliens[arrays] randomly, and shuffle
possibleAliens = GKRandomSource.sharedRandom().arrayByShufflingObjects(in: possibleAliens) as! [String]
//bring the aliens to random position
let alien = SKSpriteNode(imageNamed: possibleAliens[0])
let randomAlienPosition = GKRandomDistribution(lowestValue: 0, highestValue: 414)
//make the position constant, use randomAlien and get next integer and use CGFloat then set alien position
let position = CGFloat(randomAlienPosition.nextInt())
alien.position = CGPoint(x: position, y: self.frame.size.height + alien.size.height)
//physicsBody of addAlien
alien.physicsBody = SKPhysicsBody(rectangleOf: alien.size)
alien.physicsBody?.isDynamic = true
alien.physicsBody?.categoryBitMask = alienCategory
alien.physicsBody?.contactTestBitMask = photonTorpedoCategory
alien.physicsBody?.collisionBitMask = 0
self.addChild(alien)
//make aliens move
let animationDuration: TimeInterval = 6
//SKAction to alien will make alien move from top to bottom of the screen, then remove alien from screen and from parent so it doesnt consume too much memory
var actionArray = [SKAction]()
actionArray.append(SKAction.move(to: CGPoint(x: position, y: -alien.size.height), duration: animationDuration))
//THIS ACTION WILL SEE IF IT REACHES THE FINAL DESTINATION BEFORE IT GETS ERASED AND TAKES A LIFE
//A RUN ACTION THAT WILL PLAY SOUND WHEN PLAYER LOSES SOUND.
actionArray.append(SKAction.run{
self.run(SKAction.playSoundFileNamed("loose.mp3", waitForCompletion: false))
if self.livesArray.count > 0 {
let liveNode = self.livesArray.first
liveNode!.removeFromParent()
self.livesArray.removeFirst()
if self.livesArray.count == 0{
let transition = SKTransition.flipHorizontal(withDuration: 0.5)
let gameOver = SKScene(fileNamed: "GameOverScene") as! GameOverScene
gameOver.score = self.score
self.view?.presentScene(gameOver, transition: transition)
}
}
})
actionArray.append(SKAction.removeFromParent())
//make a run function on the alien to pass allong actionArray
alien.run(SKAction.sequence(actionArray))
}
//fire fireTorpedo when tapped
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
fireTorpedo()
}
//func FireTorpedo or bullet
func fireTorpedo(){
//adds sound, image and position of the torpedo
self.run(SKAction.playSoundFileNamed("torpedo.mp3", waitForCompletion: false))
let torpedoNode = SKSpriteNode(imageNamed: "torpedo")
//powerUp switch
switch (powerUp)
{
case 1:
torpedoNode.position.x = player.position.x
torpedoNode.position.y = player.position.y
case 2:
torpedoNode.position.y = player.position.y
torpedoNode.position.x = player.position.x - 10
torpedoNode.position.x = player.position.x + 10
default:
print("out of torpedo ammo")
break
}
torpedoNode.position.y += 5
//add physicsBody for torpedo just like the aliens
torpedoNode.physicsBody = SKPhysicsBody(circleOfRadius: torpedoNode.size.width / 2)
torpedoNode.physicsBody?.isDynamic = true
torpedoNode.physicsBody?.categoryBitMask = photonTorpedoCategory
torpedoNode.physicsBody?.contactTestBitMask = alienCategory
torpedoNode.physicsBody?.collisionBitMask = 0
torpedoNode.physicsBody?.usesPreciseCollisionDetection = true
self.addChild(torpedoNode)
//add animation like in alien
let animationDuration: TimeInterval = 0.3
//make torpedo move up and disappear
var actionArray = [SKAction]()
actionArray.append(SKAction.move(to: CGPoint(x: player.position.x, y: self.frame.size.height + 10), duration: animationDuration))
actionArray.append(SKAction.removeFromParent())
//run the torpedo
torpedoNode.run(SKAction.sequence(actionArray))
}
func didBegin(_ contact: SKPhysicsContact){
var firstBody: SKPhysicsBody
var secondBody: SKPhysicsBody
//check if two bodies touch
if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask{
firstBody = contact.bodyA
secondBody = contact.bodyB
} else {
firstBody = contact.bodyB
secondBody = contact.bodyA
}
//to findout which body is the torpedo and which is alien
if (firstBody.categoryBitMask & photonTorpedoCategory) != 0 && (secondBody.categoryBitMask & alienCategory) != 0 {
torpedoDidCollideWithAlien(torpedoNode: firstBody.node as? SKSpriteNode, alienNode: secondBody.node as? SKSpriteNode)
}
}
func torpedoDidCollideWithAlien (torpedoNode: SKSpriteNode?, alienNode: SKSpriteNode?){
if let explosion = SKEmitterNode(fileNamed: "Explosion"){
if let alien = alienNode{
explosion.position = alien.position
}
self.addChild(explosion)
self.run(SKAction.playSoundFileNamed("explosion.mp3", waitForCompletion: false))
if let torpedo = torpedoNode{
torpedo.removeFromParent()
}
if let alien = alienNode{
alien.removeFromParent()
}
//see the explosion effect longer and not disappear immediately with run function with action and completion handler
self.run(SKAction.wait(forDuration: 2)){
explosion.removeFromParent()
}
//add and update score
score += 5
}
}
override func didSimulatePhysics() {
player.position.x += xAcceleration * 50
if player.position.x < -20 {
player.position = CGPoint(x: self.size.width + 20, y: player.position.y)
} else if player.position.x > self.size.width + 20 {
player.position = CGPoint(x: -20, y: player.position.y)
}
}
}