macos - didBeginContact はまったく正しくない迅速に動作します

Question

Mac OS用のスプライトキットに関する非常にシンプルなアプリがあります。(ところで、iOS 用のこのコードは正しく動作しています)。AppDelegate コード:

import Cocoa
import SpriteKit

extension SKNode {
    class func unarchiveFromFile(file : String) -> SKNode? {
        if let path = NSBundle.mainBundle().pathForResource(file, ofType: "sks") {
        var sceneData = NSData(contentsOfFile: path, options: .DataReadingMappedIfSafe, error: nil)!
        var archiver = NSKeyedUnarchiver(forReadingWithData: sceneData)

        archiver.setClass(self.classForKeyedUnarchiver(), forClassName: "SKScene")
        let scene = archiver.decodeObjectForKey(NSKeyedArchiveRootObjectKey) as! GameScene
        archiver.finishDecoding()
        return scene
    } else {
        return nil
    }
}
}

@NSApplicationMain
class AppDelegate: NSObject, NSApplicationDelegate {

@IBOutlet weak var window: NSWindow!
@IBOutlet weak var skView: SKView!

func applicationDidFinishLaunching(aNotification: NSNotification) {
    /* Pick a size for the scene */
    if let scene = GameScene.unarchiveFromFile("GameScene") as? GameScene {
        /* Set the scale mode to scale to fit the window */
        scene.scaleMode = .AspectFill

        self.skView!.presentScene(scene)

        /* Sprite Kit applies additional optimizations to improve rendering performance */
        self.skView!.ignoresSiblingOrder = true

        self.skView!.showsFPS = true
        self.skView!.showsNodeCount = true
    }
}

func applicationShouldTerminateAfterLastWindowClosed(sender: NSApplication) -> Bool {
    return true
}
}

そしてシーンコード:

import Foundation
import SpriteKit

struct Detection {
    static var no : UInt32 = 0
    static var all : UInt32 = UInt32.max
    static var monster : UInt32 = 0b1
    static var suric : UInt32 = 0b10
    static var ninja : UInt32 = 0b100
}

func random() -> CGFloat {
    return CGFloat(Float(arc4random()) / 0xFFFFFFFF)
}

func random(#min: CGFloat, max: CGFloat) -> CGFloat {
    return random() * (max - min) + min
}


func + (left: CGPoint, right: CGPoint) -> CGPoint {
    return CGPoint(x: left.x + right.x, y: left.y + right.y)
}

func - (left: CGPoint, right: CGPoint) -> CGPoint {
    return CGPoint(x: left.x - right.x, y: left.y - right.y)
}

func * (point: CGPoint, scalar: CGFloat) -> CGPoint {
    return CGPoint(x: point.x * scalar, y: point.y * scalar)
}

func / (point: CGPoint, scalar: CGFloat) -> CGPoint {
    return CGPoint(x: point.x / scalar, y: point.y / scalar)
}

#if !(arch(x86_64) || arch(arm64))
func sqrt(a: CGFloat) -> CGFloat {
return CGFloat(sqrtf(Float(a)))
}
#endif

extension CGPoint {
func length() -> CGFloat {
    return sqrt(x*x + y*y)
}

func normalized() -> CGPoint {
    return self / length()
}
}


class GameScene: SKScene, SKPhysicsContactDelegate {

let player = SKSpriteNode(imageNamed: "player.png")

override func didMoveToView(view: SKView) {

    backgroundColor = SKColor.whiteColor()

    physicsWorld.gravity = CGVectorMake(0.0, 0.0)
    physicsWorld.contactDelegate = self
    player.position = CGPoint(x: self.size.width * 0.1, y: self.size.height / 2)
    addChild(player)


    runAction(SKAction.repeatActionForever(SKAction.sequence([SKAction.runBlock(createMonster), SKAction.waitForDuration(1)])))
}

override func mouseDown(theEvent: NSEvent) {
    let location = theEvent.locationInNode(self)

    let suric = SKSpriteNode(imageNamed: "projectile.png")
    suric.position = player.position
    suric.physicsBody = SKPhysicsBody(circleOfRadius: self.size.width / 2)
    suric.physicsBody?.categoryBitMask = Detection.suric
    suric.physicsBody?.collisionBitMask = Detection.no
    suric.physicsBody?.contactTestBitMask = Detection.monster
    suric.physicsBody?.usesPreciseCollisionDetection = true
    suric.physicsBody?.dynamic = true
    suric.physicsBody?.angularVelocity = -10.0

    let offset = location - suric.position

    if offset.x < 0 {
        return
    }

    addChild(suric)

    let direc = offset.normalized()
    let shoot = direc * 1000
    let dest = shoot + suric.position

    let move = SKAction.moveTo(dest, duration: 2.0)
    let stop = SKAction.removeFromParent()
    suric.runAction(SKAction.sequence([move, stop]))

}

func suricHit(suric : SKSpriteNode?, monster : SKSpriteNode?) {
    if suric != nil && monster != nil {
        suric!.removeFromParent()
        monster!.removeFromParent()
    }
}

func didBeginContact(contact: SKPhysicsContact) {
    var first : SKPhysicsBody
    var second : SKPhysicsBody
    if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
        first = contact.bodyA
        second = contact.bodyB
    }
    else {
        first = contact.bodyB
        second = contact.bodyA
    }

    if (first.categoryBitMask & Detection.monster != 0) && (second.categoryBitMask & Detection.suric != 0) {
        suricHit(first.node as? SKSpriteNode, monster: second.node as? SKSpriteNode)
    }
}

func createMonster() {
    let monster = SKSpriteNode(imageNamed: "monster.png")

    let y = random(min: monster.size.height / 2, size.height - monster.size.height)
    monster.position = CGPoint(x: self.size.width + monster.size.width / 2, y: y)
    monster.physicsBody = SKPhysicsBody(rectangleOfSize: monster.size, center: CGPoint(x: monster.position.x / 2, y: monster.position.y))
    monster.physicsBody?.usesPreciseCollisionDetection = true
    monster.physicsBody?.categoryBitMask = Detection.monster
    monster.physicsBody?.contactTestBitMask = Detection.suric
    monster.physicsBody?.collisionBitMask = Detection.no
    monster.physicsBody?.dynamic = true
    addChild(monster)

    let duration = random(min: 2.0, 4.0)
    let move = SKAction.moveTo(CGPoint(x: -monster.size.width / 2, y: y), duration: NSTimeInterval(duration))
    let done = SKAction.removeFromParent()

    monster.runAction(SKAction.sequence([move, done]))
}
}

そして、連絡先機能は本当に奇妙に機能します。と が実際に接触しなくても動作suricしmonsterます。なぜこれが起こるのか分かりません。それは私のせいですか、それともXcodeのバグですか?