我一直在尝试使用 Swift 创建一个简单的 SpriteKit 应用程序。目的是让一个红球在点击时重新定位在屏幕上。但是变量 self.frame.width 和 self.frame.height 不返回可见屏幕的边界。相反,它们返回整个屏幕的边界。因为我随机选择球的位置,所以我需要可见的边界。经过数小时的研究后找不到答案。我怎样才能做到这一点?
var dot = SKSpriteNode()
let dotScreenHeightPercantage = 10.0
let frameMarginSize = 30.0
override func didMoveToView(view: SKView) {
var dotTexture = SKTexture(imageNamed: "img/RedDot.png")
dot = SKSpriteNode(texture: dotTexture)
dot.size.height = CGFloat( Double(self.frame.height) / dotScreenHeightPercantage )
dot.size.width = dot.size.height
dot.name = "dot"
reCreateDot()
}
func reCreateDot() {
dot.removeFromParent()
let dotRadius = Double(dot.size.height / 2)
let minX = Int(frameMarginSize + dotRadius)
let maxX = Int(Double(self.frame.width) - frameMarginSize - dotRadius)
let minY = Int(frameMarginSize + dotRadius)
let maxY = Int(Double(self.frame.height) - frameMarginSize - dotRadius)
let corX = randomInt(minX, max: maxX)
let corY = randomInt(minY, max: maxY)
println("result: \(corX) \(corY)")
dot.position = CGPoint(x: corX, y: corY)
self.addChild(dot)
}
func randomInt(min: Int, max:Int) -> Int {
return min + Int(arc4random_uniform(UInt32(max - min + 1)))
}
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
for touch: AnyObject in touches {
let location = touch.locationInNode(self)
let node = nodeAtPoint(location)
if node.name == "dot" {
println("Dot tapped.")
reCreateDot()
}
}
}