如何在SpriteKit中使用类似于物理的台球？

我是SpriteKit的新手，正在尝试制作台球游戏，但似乎没有正常工作。 球不会互相反弹或池提示。 我不确定我做错了什么。 这是一些球和池提示的示例代码。 任何帮助将不胜感激！

class PoolTableScene: SKScene, SKPhysicsContactDelegate { struct PhysicsCatagory { static let None : UInt32 = 0 //0 static let PokeBall : UInt32 = 0b1 //1 static let PoolCue : UInt32 = 0b1000 //5 static let All : UInt32 = UInt32.max } let ballPoke = SKSpriteNode(imageNamed:"pokeBall") let cuePool = SKSpriteNode(imageNamed: "poolCue") override func didMove(to view: SKView) { physicsWorld.contactDelegate = self self.physicsWorld.gravity = CGVector(dx: 0, dy: 0) let sceneBody = SKPhysicsBody(edgeLoopFrom: self.frame) sceneBody.friction = 0 self.physicsBody = sceneBody ballPoke.name = "ballPoke" ballPoke.size = CGSize(width: 50, height: 50) ballPoke.anchorPoint = CGPoint(x:0.5, y:0.5) ballPoke.position = CGPoint(x: self.frame.size.width*0.25, y:self.frame.size.height/2) ballPoke.zPosition = 100 ballPoke.physicsBody = SKPhysicsBody(circleOfRadius: 25) ballPoke.physicsBody?.affectedByGravity = true ballPoke.physicsBody?.restitution = 10 ballPoke.physicsBody?.linearDamping = 0 self.addChild(ballPoke) cuePool.name = "poolCue" cuePool.size = CGSize(width: 100, height: 500) cuePool.anchorPoint = CGPoint(x: 0.5, y: 0.5) cuePool.position = CGPoint(x: self.frame.size.width*0.20, y: self.frame.size.height/4) cuePool.zPosition = 100 cuePool.physicsBody = SKPhysicsBody(circleOfRadius: 50) cuePool.physicsBody?.affectedByGravity = true cuePool.physicsBody?.restitution = 10 cuePool.physicsBody?.linearDamping = 0 self.addChild(cuePool) } override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { for touch: AnyObject in touches { let positionOfTouch = touch.location(in: self) ballPoke.physicsBody?.categoryBitMask = PhysicsCatagory.PokeBall ballPoke.physicsBody?.collisionBitMask = PhysicsCatagory.BlueBall | PhysicsCatagory.OrangeBall | PhysicsCatagory.Border | PhysicsCatagory.PoolCue cuePool.physicsBody?.categoryBitMask = PhysicsCatagory.PoolCue cuePool.physicsBody?.collisionBitMask = PhysicsCatagory.BlueBall | PhysicsCatagory.OrangeBall | PhysicsCatagory.PokeBall } }