ios - SpriteKit 检测多次碰撞而不是一次(Swift 3)

Question

我的 SKScene 类中有 3 个 SKSpriteNode。其中一个是玩家，另一个是金子和不可见的完成对象，例如当玩家触摸它时，游戏就结束了。我的问题是，当玩家碰撞金币时，他的金币预算应该只增加 50 金币。然而，Xcode 检测到多次碰撞和黄金预算增加了多次。检测到 50-60 次碰撞而不是一次碰撞。我研究了如何解决这个问题。我发现我应该使用 Bool，我尝试设置 bool 但它并没有解决我的问题。有没有人可以帮助我如何检测一次碰撞？这是我的 GameScene 类代码:

import SpriteKit
import GameplayKit

class level3: SKScene, SKPhysicsContactDelegate {

    let playerFileName = "player"
    let starFileName = "50Gold"
    let goalFileName = "goal"
    let playerCategory   : UInt32 = 0x1 << 1
    let goalCategory : UInt32 = 0x1 << 2
    let starCategory : UInt32 = 0x1 << 3

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

        let goal = childNode(withName: goalFileName) as! SKSpriteNode
        let player = childNode(withName: playerFileName) as! SKSpriteNode
        let star = childNode(withName: starFileName) as! SKSpriteNode

        player.physicsBody!.categoryBitMask = playerCategory
        goal.physicsBody!.categoryBitMask = goalCategory

        star.physicsBody?.collisionBitMask = 1
        player.physicsBody?.collisionBitMask = 1
        goal.physicsBody?.collisionBitMask = 1
        goal.physicsBody?.isDynamic = true

        goal.physicsBody!.contactTestBitMask = playerCategory

        player.physicsBody?.isDynamic = true
        star.physicsBody?.isDynamic = true
        player.physicsBody?.contactTestBitMask = starCategory

        star.physicsBody?.categoryBitMask = starCategory

        func didBegin(_ contact: SKPhysicsContact) {

            // 1
            var firstBody: SKPhysicsBody
            var secondBody: SKPhysicsBody
            // 2
            if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
                firstBody = contact.bodyA
                secondBody = contact.bodyB
            } else {
                firstBody = contact.bodyB
                secondBody = contact.bodyA
            }

            if firstBody.categoryBitMask == playerCategory && secondBody.categoryBitMask == goalCategory {

                contact.bodyB.node?.removeFromParent()

            }

            if firstBody.categoryBitMask == playerCategory && secondBody.categoryBitMask == starCategory {

                PlaySceneViewController.instance.gold += 50
                print(PlaySceneViewController.instance.gold)

                contact.bodyB.node?.removeFromParent()

            }

        }
    }
}

Answer 1

是的 - 这种情况发生了。处理它的方法(在某些情况下你不能让 sprite-kit 多次调用 didBegin)是确保你的联系代码适应这个并且多次处理契约(Contract)不会导致问题(例如添加多次得分，删除多个生命，尝试访问已删除的节点或 physicsBody 等)。

有关更多详细信息和可能的解决方案，请参阅此答案:https://stackoverflow.com/a/44384390/1430420