swift - 如何在 Swift/SpriteKit 中检测与 2 个以上对象的碰撞

Question

所以我正在创建一个空气曲棍球游戏，有 5 个主要的 SKSpriteNode。我需要检测冰球与 goal1 和 goal2 之间的碰撞。当它检测到碰撞时，需要将 SKLabelNode 的 ScoreLeft 或 ScoreRight 加 1。我使用了 Gamescene.sks 文件来进行视觉表示。我评论了 didBeginContact 因为那是它不起作用的地方。先感谢您。

class GameScene: SKScene, SKPhysicsContactDelegate {

let paddle1CategoryName = "paddle1"
let paddle2CategoryName = "paddle2"
let puckCategoryName = "puck"
let goal1CategoryName = "goal1"
let goal2CategoryName = "goal2"
let scoreLeftCategoryName = "scoreLeft"
let scoreRightCategoryName = "scoreRight"
var isFingerOnPaddle1 = false
var isFingerOnPaddle2 = false


var paddle1Category: UInt32 = 0x1 << 0
var paddle2Category: UInt32 = 0x1 << 1
var puckCategory: UInt32 = 0x1 << 2
var goal1Category: UInt32 = 0x1 << 3
var goal2Category: UInt32 = 0x1 << 4

override func didMoveToView(view: SKView) {
    /* Setup your scene here */
    let borderBody = SKPhysicsBody(edgeLoopFromRect: self.frame)
    borderBody.friction = 0
    self.physicsBody = borderBody
    let paddle1 = childNodeWithName(paddle1CategoryName) as! SKSpriteNode
    let paddle2 = childNodeWithName(paddle2CategoryName) as! SKSpriteNode
    let puck = childNodeWithName(puckCategoryName) as! SKSpriteNode
    let goal1 = childNodeWithName(goal1CategoryName) as! SKSpriteNode
    let goal2 = childNodeWithName(goal2CategoryName) as! SKSpriteNode
    let scoreLeft = childNodeWithName(scoreLeftCategoryName) as! SKLabelNode
    let scoreRight = childNodeWithName(scoreRightCategoryName) as! SKLabelNode

}

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
   /* Called when a touch begins */
    var touch = touches.first! as UITouch
    var location = touch.locationInNode(self)
    if let body = physicsWorld.bodyAtPoint(location){
        if body.node!.name == paddle1CategoryName {
            print("The game has begun.")
            isFingerOnPaddle1 = true
        } else if body.node!.name == paddle2CategoryName{
            print("The game has begun.")
            isFingerOnPaddle2 = true
        }
    }
}
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
    let paddle1 = childNodeWithName(paddle1CategoryName) as! SKSpriteNode
    let paddle2 = childNodeWithName(paddle2CategoryName) as! SKSpriteNode
    let puck = childNodeWithName(puckCategoryName) as! SKSpriteNode
    let goal1 = childNodeWithName(goal1CategoryName) as! SKSpriteNode
    let goal2 = childNodeWithName(goal2CategoryName) as! SKSpriteNode
    var touch = touches.first! as UITouch
    var touchLocation = touch.locationInNode(self)
    var previousLocation = touch.previousLocationInNode(self)



    if isFingerOnPaddle1{

    let paddle1X = paddle1.position.x + (touchLocation.x - previousLocation.x)
    let paddle1Y = paddle1.position.y + (touchLocation.y - previousLocation.y)
    if (touchLocation.x <= paddle1.position.x && (touchLocation.y <= paddle1.position.y || touchLocation.y >= paddle1.position.y)){
    paddle1.position = CGPoint(x: paddle1X, y: paddle1Y)
    }
    }
    if isFingerOnPaddle2{
    let paddle2X = paddle2.position.x + (touchLocation.x - previousLocation.x)
    let paddle2Y = paddle2.position.y + (touchLocation.y - previousLocation.y)

    if (touchLocation.x >= paddle2X && (touchLocation.y >= paddle2Y || touchLocation.y < paddle2.position.y)){
        paddle2.position = CGPoint(x: paddle2X, y: paddle2Y)
    }
    }

}
/*
func didBeginContact(contact: SKPhysicsContact) {
    let scoreLeft = childNodeWithName(scoreLeftCategoryName) as! SKLabelNode
    let scoreRight = childNodeWithName(scoreRightCategoryName) as! SKLabelNode
    var score = 0
    let contactMask = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask


    switch contactMask{
    case puckCategory | goal1Category:
        if contact.bodyA.categoryBitMask == puckCategory{
            puckCategory = contact.bodyA.categoryBitMask
            goal1Category = contact.bodyB.categoryBitMask
            score++
            scoreRight.text = "\(score)"
        }else{
            puckCategory = contact.bodyB.categoryBitMask
            goal1Category = contact.bodyA.categoryBitMask
            score++
            scoreRight.text = "\(score)"
        }
    case puckCategory | goal2Category:
        if contact.bodyA.categoryBitMask == puckCategory{
            puckCategory = contact.bodyA.categoryBitMask
            goal2Category = contact.bodyB.categoryBitMask
            score++
            scoreLeft.text = "\(score)"
        }else{
            puckCategory = contact.bodyB.categoryBitMask
            goal2Category = contact.bodyA.categoryBitMask
            score++
            scoreLeft.text = "\(score)"
        }
    default:

        // Nobody expects this, so satisfy the compiler and catch
        // ourselves if we do something we didn't plan to
        fatalError("other collision: \(contactMask)")

    }
}*/
override func update(currentTime: CFTimeInterval) {
    /* Called before each frame is rendered */
}

}

Answer 1

一个问题是在函数开头使用本地 var Score = 0。去掉它。分数应该存储在游戏的模型中，以便可以应用有关获胜的逻辑，但要匹配您的代码，至少这样做。

if let score = Int(scoreLeft.text) {
  scoreLeft.text = "\(score + 1)"
}

另外还有一个问题

  case puckCategory | goal1Category:
        if contact.bodyA.categoryBitMask == puckCategory{
            puckCategory = contact.bodyA.categoryBitMask

你的意思是，如果contact.bodyA.categoryBitMask等于puckCategory，则将puckCategory设置为contact.bodyA .categoryBitMask。这是一个无操作，没有任何变化，更重要的是，您不想更改与子节点进行比较的位掩码。使 puckCategory、goal1Categoy 和 goal2Category 常量。祝你好运。

跟进 OP 评论:

因此，出于两个原因，丢弃 didBeginContact 中设置类别掩码变量的代码。 1)将像puckCategory这样的变量设置为相同的值是浪费和困惑的。 2) 由于像 puckCategory 这样的变量是与子节点位掩码进行比较的，因此如果它们确实发生变化，那将是灾难性的。该函数应该如下所示。另外，请确保在您走得太远之前为其他类型的联系人添加处理程序。

func didBeginContact(contact: SKPhysicsContact) {
    let contactMask = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask

    switch contactMask {
    case puckCategory | goal1Category:
       let scoreRight = childNodeWithName(scoreRightCategoryName) as! SKLabelNode
       if let score = Int(scoreRight.text) {
          scoreRight.text = "\(score + 1)"
       }
    case puckCategory | goal2Category:
       let scoreLeft = childNodeWithName(scoreLeftCategoryName) as! SKLabelNode
       if let score = Int(scoreLeft.text) {
          scoreLeft.text = "\(score + 1)"
       }
    default:
        // There are other contacts that need to be handled; paddle+puck,puck+wall, etc
        fatalError("other collision: \(contactMask)")
    }
}