iphone - SKAction 未按预期工作

Question

嗨，我有一系列 Action 会永远运行以在横向卷轴游戏中产生障碍。但它不是从我的纹理生成随机图片和高度，而是保留第一次运行 SKActions 时生成的相同图片和高度...

有人能解决这个问题吗？我试图不使用

NSTimer.scheduledTimerWithTimeInterval(4, target: self, selector: Selector("setUpMountains"), userInfo: nil, repeats: true)

由于某种原因它降低了我的 FPS

    func setUpMountains() {

    let gapHeight = user.size.height * 3
    var movementAmount = arc4random() % UInt32(self.frame.size.height / 3.0)

    var randomNumber = arc4random() % 3
    if randomNumber == 0 {
        mountainTexture = SKTexture(imageNamed:"RedMountain.png")
    } else if randomNumber == 1 {
        mountainTexture = SKTexture(imageNamed:"OrangeMountain.png")
    } else {
        mountainTexture = SKTexture(imageNamed:"BeigeMountain.png")
    }
    var randomMountain = SKSpriteNode(texture: mountainTexture)
    randomMountain.position = CGPointMake( CGRectGetMidX(self.frame) + self.frame.width, CGRectGetMidY(self.frame) - gapHeight - CGFloat(movementAmount))
    randomMountain.zPosition = 8
    randomMountain.physicsBody = SKPhysicsBody(texture: mountainTexture, size: mountainTexture.size())
    randomMountain.physicsBody?.dynamic = false
//        randomMountain.physicsBody?.categoryBitMask = objectCategory
    movingObjects.addChild(randomMountain)

    //spawning mountains
    var distanceToMove = self.frame.size.width + mountainTexture.size().width
    var moveMountain = SKAction.moveByX(-distanceToMove, y: 0, duration: NSTimeInterval (distanceToMove * 0.01))
    var replaceMountain = SKAction.moveByX(distanceToMove, y: 0, duration: 0)
    //var removeMountain = SKAction.removeFromParent()
    var moveAndRemoveMountain = SKAction.repeatActionForever(SKAction.sequence([moveMountain, replaceMountain]))

    randomMountain.runAction(moveAndRemoveMountain)

}

Answer 1

不要每次都加载纹理，而是将纹理缓存在数组中一次，例如以下代码中的山脉。

使用带有等待时间的SKAction序列而不是NSTimer来重复执行函数。

您不需要在设置山脉中使用 repeatActionForever 操作，因为一旦生成的障碍物离开屏幕，就会使用 removeParent 将其移除。

var mountains : [SKTexture] = []

override func didMoveToView(view: SKView) {

    mountains = [SKTexture(imageNamed:"RedMountain.png"),SKTexture(imageNamed:"OrangeMountain.png"),SKTexture(imageNamed:"BeigeMountain.png")]

    let generateMountains = SKAction.runBlock { () -> Void in
        self.setUpMountains()
    }
    let generateObstaclesPeriodically = SKAction.repeatActionForever (SKAction.sequence([generateMountains,SKAction.waitForDuration(4.0)]))
     self.runAction(generateObstaclesPeriodically)
}


func setUpMountains() {

    let gapHeight = user.size.height * 3
    var movementAmount = arc4random() % UInt32(self.frame.size.height / 3.0)

    var randomNumber = arc4random() % 3
    let mountainTexture = mountains[randomNumber]

    var randomMountain = SKSpriteNode(texture: mountainTexture)
    randomMountain.position = CGPointMake( CGRectGetMidX(self.frame) + self.frame.width, CGRectGetMidY(self.frame) - gapHeight - CGFloat(movementAmount))
    randomMountain.zPosition = 8
    randomMountain.physicsBody = SKPhysicsBody(texture: mountainTexture, size: mountainTexture.size())
    randomMountain.physicsBody?.dynamic = false
    movingObjects.addChild(randomMountain)

    //spawning mountains
    var distanceToMove = self.frame.size.width + mountainTexture.size().width
    var moveMountain = SKAction.moveByX(-distanceToMove, y: 0, duration: NSTimeInterval (distanceToMove * 0.01))
    var removeMountain = SKAction.removeFromParent()

    var moveAndRemoveMountain = SKAction.sequence([moveMountain, removeMountain])

    randomMountain.runAction(moveAndRemoveMountain)

}

要删除 SKAction，您可以在添加时为 SKAction 提供一个 key ，然后使用该 key 将其从节点中删除。

 self.runAction(generateObstaclesPeriodically, withKey: "generateObstaclesPeriodically")
 self.removeActionForKey("generateObstaclesPeriodically")