我正在创建一个游戏，其中包含一个计时器，该计时器每秒都会在屏幕上产生对象。要获得积分，你必须抓住物体。
一旦玩家达到一定数量的积分，我希望产卵率增加。
我试过这样做是通过将定时器的间隔指定为1秒的整数（SpeedNumber）值来启动并且已经创建和if语句一旦玩家达到一定量就应该将该整数更改为0.5分数。这对我来说很有意义，但它不起作用。
为什么这不起作用，我应该改变什么？
import SpriteKit
struct physicsCatagory {
static let person : UInt32 = 0x1 << 1
static let Ice : UInt32 = 0x1 << 2
static let IceTwo : UInt32 = 0x1 << 3
static let IceThree : UInt32 = 0x1 << 4
static let Score : UInt32 = 0x1 << 5
}
class GameScene: SKScene, SKPhysicsContactDelegate {
var scorenumber = Int()
var lifenumber = Int()
var SpeedNumber : Double = 0.5
var person = SKSpriteNode(imageNamed: "Person")
let Score = SKSpriteNode()
var ScoreLable = SKLabelNode()
override func didMoveToView(view: SKView) {
self.scene?.backgroundColor = UIColor.purpleColor()
physicsWorld.contactDelegate = self
self.scene?.size = CGSize(width: 640, height: 1136)
lifenumber = 0
SpeedNumber = 1
Score.size = CGSize(width: 648, height: 1)
Score.position = CGPoint(x: 320, y: -90)
Score.physicsBody = SKPhysicsBody(rectangleOfSize: Score.size)
Score.physicsBody?.affectedByGravity = false
Score.physicsBody?.dynamic = false
Score.physicsBody?.categoryBitMask = physicsCatagory.Score
Score.physicsBody?.collisionBitMask = 0
Score.physicsBody?.contactTestBitMask = physicsCatagory.IceThree
Score.color = SKColor.blueColor()
self.addChild(Score)
person.position = CGPointMake(self.size.width/2, self.size.height/12)
person.setScale(0.4)
person.physicsBody = SKPhysicsBody(rectangleOfSize: person.size)
person.physicsBody?.affectedByGravity = false
person.physicsBody?.categoryBitMask = physicsCatagory.person
person.physicsBody?.contactTestBitMask = physicsCatagory.Ice
person.physicsBody?.collisionBitMask = physicsCatagory.Ice
person.physicsBody?.dynamic = false
ScoreLable.position = CGPoint(x: self.frame.width / 2, y: 1000)
ScoreLable.text = "\(scorenumber)"
ScoreLable.fontColor = UIColor.yellowColor()
ScoreLable.fontSize = 100
ScoreLable.fontName = "Zapfino "
self.addChild(ScoreLable)
var IceThreeTimer = NSTimer.scheduledTimerWithTimeInterval(SpeedNumber, target: self, selector: ("spawnThirdIce"), userInfo: nil, repeats: true)
self.addChild(person)
}
func didBeginContact(contact: SKPhysicsContact) {
let firstBody = contact.bodyA
let secondBody = contact.bodyB
if firstBody.categoryBitMask == physicsCatagory.person && secondBody.categoryBitMask == physicsCatagory.IceThree || firstBody.categoryBitMask == physicsCatagory.IceThree && secondBody.categoryBitMask == physicsCatagory.person{
scorenumber++
if scorenumber == 5 {
SpeedNumber = 0.5
}
ScoreLable.text = "\(scorenumber)"
CollisionWithPerson(firstBody.node as! SKSpriteNode, Person: secondBody.node as! SKSpriteNode)
}
if firstBody.categoryBitMask == physicsCatagory.Score && secondBody.categoryBitMask == physicsCatagory.IceThree ||
firstBody.categoryBitMask == physicsCatagory.IceThree && secondBody.categoryBitMask == physicsCatagory.Score{
lifenumber++
if lifenumber == 3{
self.view?.presentScene(EndScene())
}
//self.view?.presentScene(EndScene())
}
}
func CollisionWithPerson (Ice: SKSpriteNode, Person: SKSpriteNode){
Person.removeFromParent()
}
func spawnThirdIce(){
var Ice = SKSpriteNode(imageNamed: "Ice")
Ice.setScale(0.9)
Ice.physicsBody = SKPhysicsBody(rectangleOfSize: Ice.size)
Ice.physicsBody?.categoryBitMask = physicsCatagory.IceThree
Ice.physicsBody?.contactTestBitMask = physicsCatagory.person | physicsCatagory.Score
Ice.physicsBody?.affectedByGravity = false
Ice.physicsBody?.dynamic = true
let MinValue = self.size.width / 8
let MaxValue = self.size.width - 20
let SpawnPoint = UInt32(MaxValue - MinValue)
Ice.position = CGPoint(x: CGFloat(arc4random_uniform(SpawnPoint)), y: self.size.height)
self.addChild(Ice)
let action = SKAction.moveToY(-85, duration: 2.5)
let actionDone = SKAction.removeFromParent()
Ice.runAction(SKAction.sequence([action,actionDone]))
}
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
for touch in touches {
let location = touch.locationInNode(self)
person.position.x = location.x
}
}
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
for touch in touches {
let location = touch.locationInNode(self)
person.position.x = location.x
}
}
override func update(currentTime: CFTimeInterval) {
/* Called before each frame is rendered */
}
}
答案 0 :(得分：1)
你可以按照以下方式做你想做的事：
首先声明2个属性（在您的类中但在所有函数定义之外）
var timeOfLastSpawn: CFTimeInterval = 0.0
var timePerSpawn: CFTimeInterval = 1.0
然后，在Update中，检查是否已超出timePerSpawn。如果是这样，请调用生成新对象的spawn进程，然后重置自上次生成以来的时间：
override func update(currentTime: CFTimeInterval) {
/* Called before each frame is rendered */
if (currentTime - timeOfLastSpawn > timePerSpawn) {
spawnObject()
self.timeOfLastSpawn = currentTime
}
}
func spawnObject() {
// Your spawn code here
}
使生成过程成为一个单独的函数的优点是你可以从didMoveToView或任何其他地方调用它来生成正常时间控制周期之外的对象。
您可以根据需要更改timePerSpawn的值，以控制生成对象的速率。
您还可以考虑创建一个以指定的时间间隔运行SKAction的{{1}}，但我认为要更改生成对象的速率，您必须删除并重新创建 - 创建SKAction，但你可以在timePerSpawn的setter中执行此操作。
你不应该真正使用NSTimer是SpriteKit，因为SpriteKit引擎将不知道计时器正在做什么并且无法控制它（一个例子是如果设置场景，计时器继续运行暂停了。）
答案 1 :(得分：0)
您应该将var IceThreeTimer的声明移动到类级别（在方法之外，在您声明SpeedNumber的位置。这将确保指针的句柄在两者中都可用didMoveToView和didBeginContact方法。
在didMoveToView中，您将声明更改为：
// I removed the "var"
IceThreeTimer = NSTimer.scheduledTimerWithTimeInterval(SpeedNumber, target: self, selector: ("spawnThirdIce"), userInfo: nil, repeats: true)
然后在didBeginContact修改：
if scorenumber == 5 {
SpeedNumber = 0.5
// Stop the already running timer
IceThreeTimer.invalidate()
// Schedule a new timer
IceThreeTimer = NSTimer.scheduledTimerWithTimeInterval(SpeedNumber, target: self, selector: ("spawnThirdIce"), userInfo: nil, repeats: true)
}