我想在随机位置创建一些精灵而不会重叠,这是我的代码:
var sprites = [SKSpriteNode]()
for index in 0...spriteArray {
let sprite = SKSpriteNode(imageNamed: named)
sprites.append(sprite)
checkInterception(sprite, sprite2: sprites)// positioning using a function
addChild(sprite)
}
我在这里检查重叠:
func checkInterception(sprite1: SKSpriteNode, sprite2: [SKSpriteNode]) {
let xPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxX
let yPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxY
sprite1.position = CGPoint(x: xPos, y: yPos )
for index in 0...sprite2.count-1 {
if sprite1.intersectsNode(sprite2[index]) {
let yPos = sprite1.position.y + sprite1.size.height
sprite1.position = CGPoint(x: xPos, y: yPos )
}
}
}
但是一些精灵仍然会重叠。我知道for循环有一些不对的东西,但是无法理解。
答案 0 :(得分:4)
我确信有几种不同的方法来解决问题,这将是你最接近你已经写的。
let sprites = [SKSpriteNode]() //loaded with your sprites to spawn
let maxX = size.width //whatever your max is
let maxY = size.height //whatever your max is
var spritesAdded = [SKSpriteNode]()
for currentSprite in sprites{
addChild(currentSprite)
var intersects = true
while (intersects){
let xPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxX
let yPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxY
currentSprite.position = CGPoint(x: xPos, y: yPos )
intersects = false
for sprite in spritesAdded{
if (currentSprite.intersectsNode(sprite)){
intersects = true
break
}
}
}
spritesAdded.append(currentSprite)
}
要考虑的事项是,如果您还不知道添加精灵的安全位置,则会存在性能风险。例如,添加你的最后一个精灵可能需要1,000,000次尝试才能随机选择一个与其他精灵不相交的点。
如果您不必立即将它们全部添加,我会在更新循环上攻击问题并执行类似的操作...
var sprites = [SKSpriteNode]() //loaded with your sprites to spawn
var maxX : CGFloat = 0.0 //whatever your max is
var maxY : CGFloat = 0.0 //whatever your max is
var spritesAdded = [SKSpriteNode]()
override func didMoveToView(view: SKView) {
maxX = size.width //whatever your max is
maxY = size.height //whatever your max is
}
func addSprite(){
if let currentSprite = sprites.first {
let xPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxX
let yPos = CGFloat( Float(arc4random()) / Float(UINT32_MAX)) * maxY
currentSprite.position = CGPoint(x: xPos, y: yPos )
for sprite in spritesAdded{
if (currentSprite.intersectsNode(sprite)){
return
}
}
addChild(currentSprite)
spritesAdded.append(currentSprite)
sprites.removeFirst()
}
}
override func update(currentTime: NSTimeInterval) {
addSprite()
}
有点粗糙,但想法是每次更新都会尝试添加精灵。这样,如果你没有房间,它将无法锁定。希望这会有所帮助。