swift - 在 SpriteKit SKPhysicsContactDelegate 中未检测到接触

Question

我正在尝试使用 Spritekit 在 Swift 中编写游戏。目的是带着他的角色迎面而来的矩形逃跑。现在我在 SKPhysicsContactDelegate (didBegin ()) 方法中犯了一个错误，因此无法识别图形与矩形之一的接触。有人可以帮我找出错误吗？

    import SpriteKit

enum bodyType: UInt32 {
    case rechteckRechts = 1
    case rechteckLinks = 2
    case figur = 4
}

class PlayScene: SKScene, SKPhysicsContactDelegate {

    let figur = SKSpriteNode(imageNamed: "Punkt.jpg")

    @objc func addRechteck(){
        let rechteckRechts = SKSpriteNode(imageNamed: "Rechteck.gif")
        rechteckRechts.physicsBody = SKPhysicsBody()
        rechteckRechts.physicsBody?.isDynamic = false
        rechteckRechts.physicsBody?.categoryBitMask = bodyType.rechteckRechts.rawValue

        let rechteckLinks = SKSpriteNode(imageNamed: "Rechteck.gif")
        rechteckLinks.physicsBody = SKPhysicsBody()
        rechteckLinks.physicsBody?.isDynamic = false
        rechteckLinks.physicsBody?.categoryBitMask = bodyType.rechteckLinks.rawValue

        let groesse = arc4random_uniform(5)+1
        print(groesse)

        switch groesse {
        case 1:
            rechteckLinks.xScale = 0.5
            rechteckRechts.xScale = 1.5
        case 2:
            rechteckLinks.xScale = 1.5
            rechteckRechts.xScale = 0.5
        case 3:
            rechteckLinks.xScale = 1
            rechteckRechts.xScale = 1
        case 4:
            rechteckLinks.xScale = 1.25
            rechteckRechts.xScale = 0.75
        case 5:
            rechteckLinks.xScale = 0.75
            rechteckRechts.xScale = 1.25
        default:
            print("Fehler in der Wahrscheinlichkeit!!!")
        }
        rechteckRechts.position = CGPoint(x: frame.minX + (rechteckRechts.size.width / 2), y: frame.maxY)
        rechteckLinks.position = CGPoint(x: frame.maxX - (rechteckLinks.size.width / 2), y: frame.maxY)

        let moveDown = SKAction.moveBy(x: 0, y: -5000, duration: 20.0)
        rechteckLinks.run(moveDown)
        rechteckRechts.run(moveDown)

        self.addChild(rechteckRechts)
        self.addChild(rechteckLinks)
    }

    override func didMove(to view: SKView) {
        physicsWorld.gravity = .zero
        physicsWorld.contactDelegate = self

        figur.xScale = 0.4
        figur.yScale = 0.4
        figur.position = CGPoint(x: frame.midX, y: frame.maxY / 4)
        figur.physicsBody = SKPhysicsBody()
        figur.physicsBody?.isDynamic = false
        figur.physicsBody?.categoryBitMask = bodyType.figur.rawValue
        self.addChild(figur)

        self.backgroundColor = SKColor.white

        let wait1 = SKAction.wait(forDuration: 3)
        let timer = SKAction.repeatForever(SKAction.sequence([wait1, SKAction.run {
            self.addRechteck()
            }]))
        self.run(timer, withKey: "addRechteck")

    }

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

        switch contactMask {
        case bodyType.figur.rawValue | bodyType.rechteckLinks.rawValue:
            print("contact")
        case bodyType.figur.rawValue | bodyType.rechteckRechts.rawValue:
            print("contact")
        default:
            return
        }
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        for touch in (touches ){
            let location = touch.location(in: self)
            if figur.contains(location){
                figur.position = location
            }
        }
    }

    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
        for touch in (touches ) {
            let location = touch.location(in: self)
            if figur.contains(location){
                figur.position = location
            }
        }
    }
}

Answer 1

您似乎没有设置碰撞和接触测试位掩码。这些是物理体的属性。 CollisionBitMask 控制哪些对象从哪些其他对象反弹。默认情况下，一切都会从其他一切中反弹。

在这种情况下，contactTestBitMask 是重要的，因为它控制哪些对象在联系其他对象时调用“didBegin”。默认情况下，该值为 0，表示没有注册任何联系人。在这里查看我的答案:https://stackoverflow.com/a/40596890/1430420详细解释。

在您的具体示例中，您似乎想知道 figur 何时与 rechteckLinks 或 rechteckRechts 联系，因此您需要以下contactTestBitMasks:

figur.physicsBody!.cagegoryBitMask = bodyType.figur
figur.physicsBody!.contactTestBitMask = bodyType.rechteckRechts | bodyType.rechteckLinks

编辑:更正figur物理体的定义:

我们改变？到 !这样，如果物理体不存在，我们就会崩溃。我们还将 isDynamic 属性更改为 true，因为非动态的物理体无法注册接触(我认为)。其他两个不动态也没关系。我们将collisionTestBitMask分配给我们想要收到碰撞通知的所有类别的值，并通过逻辑“或”组合在一起:

figur.physicsBody!.isDynamic = true 
figur.physicsBody!.categoryBitMask = bodyType.figur.rawValue
figur.physicsBody!.contactTestBitMask = bodyType.rechteckRechts.rawValue | bodyType.rechteckLinks.rawValue