swift - 如何循环动态延迟的 SKActions 序列

Question

我需要运行未知数量(来自字典数组)的 SKAction 序列，这些序列是动态创建的，并使用随着循环进行而增加的延迟在循环中进行偏移。循环的打印输出应按以下顺序出现

show line 5
hiding everything
show line 6
hiding everything
show line 2
hiding everything

为了获得这个功能，我使用了这段代码

func display(winningLines: [Int : AnyObject]) {

    var delay = 0.0
    var actions = [SKAction]()

    let hideAction = SKAction.run {
        print("hiding everything")
    }

    for winningLine in winningLines {

        let displayAction = SKAction.run {
            print("line \(winningLine.key)")
        }

        let wait = SKAction.wait(forDuration: delay)            
        var action: SKAction!

        //repeatForever = true
        if !repeatForever {
             action = SKAction.sequence([wait, displayAction, SKAction.wait(forDuration: 1.0), hideAction])
        }
        else {
            let seq = SKAction.sequence([wait, displayAction, SKAction.wait(forDuration: 1.0), hideAction])
            action = SKAction.repeatForever(seq)
        }
        self.run(action)

        delay += 1.0
    }
}

如果序列只需要发生一次而不是按预期输出，但是有时我需要序列永远重复(直到用户停止操作)。在 Action 周围永远重复是行不通的，因为它会重复每个单独的序列并打乱顺序。第一个序列将每 1 秒重复一次，第二个序列将每 2 秒重复一次......等等。

关于如何让它永远正确循环的任何建议？

line 5
hiding everything
line 5
line 6
hiding everything
line 5
hiding everything
line 2
hiding everything
line 5
line 6
hiding everything
hiding everything
line 5
hiding everything
hiding everything
line 5
line 6
line 2
hiding everything
line 5
hiding everything
hiding everything

我也试过将 Action 附加到 SKActions 数组并在最后循环遍历它们，但它没有用

var actions = [SKAction]()

...

actions.append(action)

for action in actions {
    self.run(action)
}

Answer 1

如果您唯一关心的是永远重复未知数量的序列，您可以执行以下操作:

• 创建所有需要的序列
• 将它们放在另一个序列中
• 永远循环

因此，例如，此代码将创建四个框，并将淡入/淡出(代码中的 displayAction/hideAction)依次应用到每个框，并将永远重复:

import SpriteKit

class GameScene: SKScene {

var boxes:[SKSpriteNode] = []

override func didMove(to view: SKView) {

    let distance:CGFloat = 10

    for i in 0...3 {

        let box = SKSpriteNode(color: .purple, size: CGSize(width: 50, height: 50))
        box.name = String(i) //name == index
        box.position.x = CGFloat(i) * (box.size.width + distance)
        box.alpha = 0.0
        addChild(box)
        boxes.append(box)

    }
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

    var actions:[SKAction] = []

    let action = SKAction.sequence([

        SKAction.fadeIn(withDuration: TimeInterval(1)),
        SKAction.fadeOut(withDuration: 0),
    ])

    for index in 0...boxes.count {

        let sequence = SKAction.sequence([
            SKAction.run(action, onChildWithName: String(index)),
            SKAction.wait(forDuration: 1)
        ])

        actions.append(sequence)

    }

    self.run(SKAction.repeatForever(SKAction.sequence(actions)))
}
}