ios - 为 SKSpriteNode 生成位置

Question

我正在为 SKSpriteNode 生成 Y 位置。我需要生成 y 位置，但它不应该在先前生成图像的位置，不应该重叠。我怎样才能在 SpriteKit 的 Swift 中做到这一点？

for _ in 1...3 {
        let lower : UInt32 = 100
        let upper : UInt32 = UInt32(screenSize.height) - 100
        let randomY = arc4random_uniform(upper - lower) + lower

        obstaclesTexture = SKTexture(imageNamed: "levaPrekazka")
        obstacle = SKSpriteNode(texture: obstaclesTexture)
        prekazka = obstacle.copy() as! SKSpriteNode

        prekazka.name = "prekazka"
        prekazka.position = CGPoint(x: 0, y: Int(randomY))
        prekazka.zPosition = 10;
        prekazka.size = CGSize(width: screenSize.width / 7, height: screenSize.height / 7)
        prekazka.physicsBody = SKPhysicsBody(texture: obstaclesTexture, size: obstacle.size)
        prekazka.physicsBody?.dynamic = false
        prekazka.physicsBody?.categoryBitMask = PhysicsCatagory.obstacle
        prekazka.physicsBody?.contactTestBitMask = PhysicsCatagory.ball
        prekazka.physicsBody?.contactTestBitMask  = PhysicsCatagory.ball
        self.addChild(prekazka)
    }

Answer 1

为了避免两者重叠 Sprite 和不同的位置，您需要考虑 Sprite 的高度。 可能是这样的:

let spriteHeight = 60 // or whatever
let lower  = 100
let upper = Int(screenSize.height) - 100
let area = upper - lower
let ySpacing = area/spriteHeight
var allowedYs = Set<CGFloat>()
let numberOfSprites = 3

while allowedYs.count < numberOfSprites {
    let random = arc4random_uniform(UInt32(spriteHeight))
    let y = CGFloat(random) * CGFloat(ySpacing)
    allowedYs.insert(y)
}

for y in allowedYs {
    obstaclesTexture = SKTexture(imageNamed: "levaPrekazka")
    obstacle = SKSpriteNode(texture: obstaclesTexture)
    prekazka = obstacle.copy() as! SKSpriteNode

    prekazka.name = "prekazka"
    prekazka.position = CGPoint(x: 0, y: y)
    // etc...
}