当节点靠近时启动动画

Question

我有2个带纹理节点（SKSpriteNode），我试图创建一些动画，当节点靠近另一个带有y轴的节点（范围100 - 0）并且动画在此处开始时时刻。 我试图做一些类似于割绳子的事情，当糖果在Om-Nom附近时，他张开嘴要抓住糖果。 帮我看看代码，请（ 对不起，我的英语

Answer 1

你可以实现这种计算的少量代码行：

class GameScene: SKScene { 
    var sprite1 : SKSpriteNode! 
    var sprite2 : SKSpriteNode! 
    var range : CGFloat = 0.0 
    override func didMoveToView(view: SKView) { 
     self.range = randomCGFloat(0.0, max: 100.0) 
     sprite1 = SKSpriteNode.init(color: SKColor.blueColor(), size: CGSizeMake(40,40)) 
     sprite2 = SKSpriteNode.init(color: SKColor.redColor(), size: CGSizeMake(40,40)) 
     addChild(sprite1) 
     addChild(sprite2) 
     // Try to generate 10 positions and check relative distance 
     print("The range to check is :\(range)") 
     for i in 0...9 { 
      print("\(i)) time:") 
      let isNear = checkDistanceBtwSprites() 
      if isNear { 
       // do whatever you want with your sprites 
      } 
     } 
    } 
    func checkDistanceBtwSprites()->Bool{ 
     sprite1.position = getRandomPosition(40, maxX: 40, minY: 0, maxY: 320) 
     sprite2.position = getRandomPosition(40, maxX: 40, minY: 0, maxY: 320) 
     let distance = getDistance((sprite1.position), p2: (sprite2.position)) 
     print("distance for sprite1 and sprite2 is : \(distance)") 
     if distance <= self.range { 
      print("# -> success: sprite1 is near sprite2") 
      return true 
     } 
     return false 
    } 
    func getRandomPosition(minX: CGFloat, maxX: CGFloat, minY:CGFloat, maxY:CGFloat)->CGPoint { 
     return CGPointMake(randomCGFloat(minX, max: maxX),randomCGFloat(minY, max: maxY)) 
    } 
    func randomCGFloat(min: CGFloat, max: CGFloat)->CGFloat { 
     return (CGFloat(arc4random())/CGFloat(UINT32_MAX)) * (max - min) + min 
    } 
    func getDistance(p1:CGPoint,p2:CGPoint)->CGFloat { 
     let xDist = (p2.x - p1.x) 
     let yDist = (p2.y - p1.y) 
     return CGFloat(sqrt((xDist * xDist) + (yDist * yDist))) 
    } 
} 

输出：