ios - 如何将随机纹理与另一个纹理匹配以进行动画处理？

Question

我有一个球，我有不同的颜色。球有两个纹理(texture1 和 texture2)，我运行它们来为它们制作动画。我有不同颜色的球。一旦我调用一个随机函数来调用任何随机球 (texture1)，我的另一个函数就不会将它与相同的球颜色 (texture2) 匹配。例如，如果我的 texture1 调用了 redBallUp，我的其他函数没有将它与 redballDown 匹配，而是随机调用了一个纹理。有时，它匹配上了，但动画一直在不同纹理之间切换，有时，它根本不调用 texture2。

我是这样设置的:

class GameScene: SKScene {

override func didMoveToView(view: SKView) {
     let ballTexture1 = SKTexture(imageNamed: getRandomBallUp())
     ballTexture1.filteringMode = SKTextureFilteringMode.Nearest
     let ballTexture2 = SKTexture(imageNamed: getRandomBalldDown())
     ballTexture2.filteringMode = SKTextureFilteringMode.Nearest

    let anim = SKAction.animateWithTextures([ballTexture1, ballTexture2], timePerFrame: 0.15)
    let upDown = SKAction.repeatActionForever(anim)

    ball = SKSpriteNode(texture: ballTexture1)
    ball.position = CGPoint(x: self.frame.size.width / 2.8, y:CGRectGetMidY(self.frame))
    ball.runAction(upDown)

    self.addChild(ball)
    }

func getRandomBallUp() -> String{
    let randomval = arc4random_uniform(6)
    var ballUp = ""
    switch(randomval)
    {
    case 0:
        ballUp = "BlueBallUp"
    case 1:
        ballUp = "DarkBlueBallUp"
    case 2:
        ballUp = "GreenBallUp"
    case 3:
        ballUp = "PurpleBallUp"
    case 4:
        ballUp = "RedBallUp"
    case 5:
        ballUp = "YellowBallUp"
    default:()
    }
    return ballUp
}

func getRandomBallDown() -> String{
    var ballDown = ""
    if (getRandomBallUp() == "BlueBallUp") {
        ballDown = "BlueBallDown"
    }
    if (getRandomBallUp() == "DarkBlueBallUp") {
        ballDown = "DarkBlueBallDown"
    }
    if (getRandomBallUp() == "GreenBallUp") {
        ballDown = "GreenBallDown"
    }
    if (getRandomBallUp() == "PurpleBallUp") {
        ballDown = "PurpleBallDown"
    }
    if (getRandomBallUp() == "RedBallUp") {
        ballDown = "RedBallDown"
    }
    else if (getRandomBallUp() == "YellowBallUp") {
        ballDown = "YellowBallDown"
    }
    return ballDown
}

Answer 1

每次调用 getRandomBallUp() 时，您都会生成一个随机值并返回基于该值的字符串。为避免这种情况，您需要将 getRandomBallDown() 更改为类似以下内容:

func getCorrespondingRandomBallDown(ballUp:String) -> String{
    var ballDown = ""
    if (ballUp == "BlueBallUp") {
        ballDown = "BlueBallDown"
    }
    if (ballUp == "DarkBlueBallUp") {
        ballDown = "DarkBlueBallDown"
    }
    if (getRandomBallUp() == "GreenBallUp") {
        ballDown = "GreenBallDown"
    }
    if (ballUp == "PurpleBallUp") {
        ballDown = "PurpleBallDown"
    }
    if (ballUp == "RedBallUp") {
        ballDown = "RedBallDown"
    }
    else if (ballUp == "YellowBallUp") {
        ballDown = "YellowBallDown"
    }
    return ballDown
}

您还需要更改您的 didMoveToView:

override func didMoveToView(view: SKView) {
     let ballUp = getRandomBallUp()
     let ballTexture1 = SKTexture(imageNamed: ballUp)
     ballTexture1.filteringMode = SKTextureFilteringMode.Nearest
     let ballTexture2 = SKTexture(imageNamed: getCorrespondingRandomBallDown(ballUp)
     ballTexture2.filteringMode = SKTextureFilteringMode.Nearest

    let anim = SKAction.animateWithTextures([ballTexture1, ballTexture2], timePerFrame: 0.15)
    let upDown = SKAction.repeatActionForever(anim)

    ball = SKSpriteNode(texture: ballTexture1)
    ball.position = CGPoint(x: self.frame.size.width / 2.8, y:CGRectGetMidY(self.frame))
    ball.runAction(upDown)

    self.addChild(ball)
    }