ios - 使用 SpriteKit 设置地面节点？

Question

我一直在设计一款游戏，希望球一接触地面就停止游戏。我下面的功能是为了设置地面。

class GameScene: SKScene, SKPhysicsContactDelegate {

     var ground = SKNode() 

     let groundCategory: UInt32 = 0x1 << 0
     let ballCategory: UInt32 = 0x1 << 1

     //Generic Anchor coordinate points
     let anchorX: CGFloat = 0.5
     let anchorY: CGFloat = 0.5
     /*Sets the background and ball to be in the correct dimensions*/

     override init(size: CGSize) {
         super.init(size: size)

         //Create the Phyiscs of the game
         setUpPhysics()  

         setUpGround()   

         setUpBall()
    }

    func setUpPhysics() -> Void {
        self.physicsWorld.gravity = CGVectorMake( 0.0, -5.0 )
        self.physicsWorld.contactDelegate = self
    }

     func setUpGround() -> Void {
        self.ground.position = CGPointMake(0, self.frame.size.height)
        self.ground.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake(self.frame.size.width, self.frame.size.height)) //Experiment with this
        self.ground.physicsBody?.dynamic = false

        self.ground.physicsBody?.categoryBitMask = groundCategory    //Assigns the bit mask category for ground
        self.ball.physicsBody?.contactTestBitMask = ballCategory  //Assigns the contacts that we care about for the ground

        /*Added in*/
        self.ground.physicsBody?.dynamic = true

        self.ground.physicsBody?.affectedByGravity = false
        self.ground.physicsBody?.allowsRotation = false
        /**/

        self.addChild(self.ground)
    }

    func setUpBall() -> Void {

        ball.anchorPoint = CGPointMake(anchorX, anchorY)

        self.ball.position = CGPointMake(self.frame.size.width/2, self.frame.size.height/2)

        self.ball.name = "ball"
        self.ball.userInteractionEnabled = false

        ball.physicsBody?.usesPreciseCollisionDetection = true

        self.ball.physicsBody?.categoryBitMask = ballCategory    //Assigns the bit mask category for ball
        self.ball.physicsBody?.collisionBitMask = wallCategory | ceilingCategory //Assigns the collisions that the ball can have
        self.ball.physicsBody?.contactTestBitMask = groundCategory   //Assigns the contacts that we care about for the ball

        addChild(self.ball)  //Add ball to the display list
    }

我注意到的问题是，当我运行 iOS 模拟器时，未检测到接地节点。在这种情况下我做错了什么？

Answer 1

你的地面节点根本没有出现吗？我相信你的地面应该是一个 SKSpriteNode。将该 SKSpriteNode 添加为您创建的 SKNode 对象的子对象。SKNode 是一个空节点，而 SKSpriteNode 具有实际的视觉表示。与其在单独的函数中执行，不如在 DidMoveToView 本身中执行会简单得多。

var objects = SKNode()
addChild(objects)
let ground = SKNode()
ground.position = .......
let colorsprite1 = SKSpriteNode(imageNamed: "yourimageoftheground")
ground.addChild(colorsprite1)
ground.physicsBody?.dynamic = false

是的，您将地面的物理定义设置为非动态是正确的。我不知道为什么人们不这么告诉你。你不希望它在接触到你的球或你在场景中移动的任何东西时移动。

添加您需要的所有其他物理定义。考虑使用 ContactTestBitMask，因为您希望 SpriteKit 通知您何时发生与地面的碰撞，而不是 SpriteKit 自己处理。在 StackOverFlow 中可以通过示例轻松获得有关该掩码的详细信息。

objects.addChild(ground)

希望对你有帮助