从 GameScene 设置自定义 SKSpriteNode 的位置

Question

我正在制作一个自定义的 SKSpriteNode，当我逐步调用 createShip 时，类中的 heroShip 常量是正确的，但是当我跳回游戏场景时，那里的 heroShip 常量没有我在调用 createShip 时分配的属性，我我不确定我做错了什么。我尝试过使用类函数，但使用 height 和 width 属性不起作用。

自定义 SKSpriteNode 类

class hero: SKSpriteNode {
    var width: CGFloat = 0.0
    var height: CGFloat = 0.0

     func createShip() -> SKSpriteNode {
        let heroShip = SKSpriteNode(imageNamed: "heroShip")
            heroShip.anchorPoint = CGPointMake(1.0, 0.5)
            heroShip.physicsBody = SKPhysicsBody(rectangleOfSize: heroShip.size)
            heroShip.physicsBody?.usesPreciseCollisionDetection = true
              heroShip.zPosition = 1.0
            heroShip.physicsBody?.mass = 0.02
            heroShip.physicsBody?.dynamic = true
            heroShip.physicsBody?.affectedByGravity = false
            heroShip.physicsBody?.categoryBitMask = ObjectCategory.collisionHeroCategory.rawValue
            heroShip.physicsBody?.contactTestBitMask = ObjectCategory.sceneCategory.rawValue
            heroShip.physicsBody?.collisionBitMask = 0x0 | ObjectCategory.sceneCategory.rawValue

            //heroShip.position = CGPointMake((scene?.frame.size.width)!/6.0, (scene?.frame.size.height)!/2.0)

        heroShip.position = CGPointMake(width, height)

        return heroShip


    }
}

我的游戏场景

class GameScene: SKScene,SKPhysicsContactDelegate{


    let background = SKSpriteNode(imageNamed: "background")
    var score:Int = 0
    let scoreLabel = SKLabelNode(fontNamed: "Courier")
    let MotionManager = CMMotionManager()
    var heroShip = hero()
    override func didMoveToView(view: SKView) {
        heroShip.width = self.size.width/6.0
        heroShip.height = self.size.height/2.0
        heroShip.createShip()
        let enemyShip = SKSpriteNode(imageNamed: "enemyShip")
        /* Setup your scene here */
        self.physicsWorld.contactDelegate = self
        self.physicsBody = SKPhysicsBody(edgeLoopFromRect: CGRectMake(0,heroShip.size.width/1.25,frame.width,frame.height - heroShip.size.width*1.6))
        scene?.physicsBody?.contactTestBitMask = ObjectCategory.sceneCategory.rawValue
        scene?.physicsBody?.categoryBitMask = ObjectCategory.sceneCategory.rawValue
        background.position = CGPointMake(CGRectGetMidX(self.frame),CGRectGetMidY(self.frame))
        scoreLabel.fontColor = SKColor.whiteColor()
        scoreLabel.text = String(format: "Score: %01u",score)
        scoreLabel.position = CGPointMake(frame.size.width/2, frame.size.height - scoreLabel.frame.size.width/1.2)
        scoreLabel.zPosition = 1.0


        enemyShip.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))
        enemyShip.zPosition = 1.0
        enemyShip.physicsBody = SKPhysicsBody(rectangleOfSize: heroShip.size)
        enemyShip.physicsBody?.usesPreciseCollisionDetection = true
        enemyShip.physicsBody?.mass = 0.02
        enemyShip.physicsBody?.dynamic = true
        enemyShip.physicsBody?.affectedByGravity = false
        enemyShip.physicsBody?.categoryBitMask = ObjectCategory.collisionEnemyCategory.rawValue
        enemyShip.physicsBody?.contactTestBitMask = ObjectCategory.collisionBulletCategory.rawValue
        enemyShip.physicsBody?.collisionBitMask = 0x0

        self.addChild(enemyShip)
        self.addChild(background)
        self.addChild(self.heroShip)
        self.addChild(scoreLabel)

        if MotionManager.accelerometerAvailable{
            MotionManager.startAccelerometerUpdates()
        }

    }

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        let bullet = SKSpriteNode(imageNamed: "bullet")
        bullet.position = CGPointMake(heroShip.position.x, heroShip.position.y)
        bullet.zPosition = 1.0
        // Add physics body for collision detection
        bullet.physicsBody = SKPhysicsBody(rectangleOfSize: bullet.frame.size)
        bullet.physicsBody?.dynamic = true
        bullet.physicsBody?.affectedByGravity = false
        bullet.physicsBody?.categoryBitMask = ObjectCategory.collisionBulletCategory.rawValue
        bullet.physicsBody?.contactTestBitMask = ObjectCategory.collisionHeroCategory.rawValue
        bullet.physicsBody?.collisionBitMask = 0x0;
        let action = SKAction.moveToX(CGRectGetMaxX(self.frame) + bullet.size.width, duration: 0.75)
        self.addChild(bullet)
        bullet.runAction(action, completion: {
            bullet.removeAllActions()
            bullet.removeFromParent()
        })
    }

    func didBeginContact(contact: SKPhysicsContact) {
        if contact.bodyB.categoryBitMask == ObjectCategory.collisionBulletCategory.rawValue && contact.bodyA.categoryBitMask == ObjectCategory.collisionEnemyCategory.rawValue{
        score++
        }
    }



    override func update(currentTime: CFTimeInterval) {
        let data = MotionManager.accelerometerData
        if data?.acceleration.x == nil{
            print("nil")
        }
        else if fabs((data?.acceleration.x)!) > 0.2 {
            heroShip.physicsBody?.applyForce(CGVectorMake(0.0, CGFloat(40 * (data?.acceleration.x)!)))
        }

        scoreLabel.text = String(format: "Score: %01u",score)


    }
}

Answer 1

你跑

heroShip.createShip()

然后永远不要对返回的SKSpriteNode 做任何事情。据我所知，英雄级是英雄船。对于这个答案的其余部分，我将放弃这个假设。

从GameScene 的顶部开始，您应该进行一些重构。

var heroShip = hero() 将被替换为使用SKSpriteNode 结构的init：

var heroShip = hero(imageNamed: "heroShip")

移动到hero 类，func createShip() -> SKSpriteNode { 应该变成func createShip() {。由于您现在已经使用图像纹理设置了节点，并且正在使用 hero 类作为节点，因此无需返回 SKSpriteNode。

删除let heroShip = SKSpriteNode(imageNamed: "heroShip")，因为hero 类是将成为我们的heroShip。

将heroShip.whatever 变量的所有用法替换为self.whatever。最后删除return heroShip。

Answer 2

您似乎不了解您的代码发生了什么。

截至目前createShip() 正在创造一艘英雄船，但你从未使用它。

通过查看您的代码，似乎甚至不需要createShip()。从表面上看， hero 就是 heroShip，你的 init 中的代码也是如此。

    convenience init(imageNamed: String,sceneSize:CGSize) {
    let heroTexture = SKTexture(imageNamed: imageNamed)

    self.init(texture: heroTexture, color: UIColor.whiteColor(), size: heroTexture.size()) //This may need to be tweeked, my mac is dead right now to verify.
    self.anchorPoint = CGPointMake(1.0, 0.5)
    self.physicsBody = SKPhysicsBody(rectangleOfSize: self.size)
    self.physicsBody?.usesPreciseCollisionDetection = true
    self.zPosition = 1.0
    self.physicsBody?.mass = 0.02
    self.physicsBody?.dynamic = true
    self.physicsBody?.affectedByGravity = false
    heroShip.physicsBody?.categoryBitMask = ObjectCategory.collisionHeroCategory.rawValue
        heroShip.physicsBody?.contactTestBitMask = ObjectCategory.sceneCategory.rawValue
        heroShip.physicsBody?.collisionBitMask = 0x0 | ObjectCategory.sceneCategory.rawValue

    //self.position = CGPointMake((scene?.frame.size.width)!/6.0, (scene?.frame.size.height)!/2.0)

    self.position = CGPointMake(sceneSize.width, sceneSize.height)



}

您现在遇到了另一个问题，那就是您的 SKPhysicsBody 不会与您的锚点对齐。

要解决此问题，请像这样创建SKPhysicsBody：

let centerPoint = CGPointMake(self.size.width / 2 - (self.size.width * self.anchorPoint.x), self.size.height / 2 - (self.size.height * self.anchorPoint.y))
self.physicsBody = SKPhysicsBody(rectangleOfSize: self.size, center: centerPoint)