arrays - SpriteKit & Swift，是否可以使用数组来汇集 SKSpritenodes？

Question

我正在开发一个带有平台、障碍物等的 2d siderunner 游戏。平台正在创建，然后从右向左移动，然后再次移除。这就是我的问题，因为每次创建和删除节点都不是很有效，我有时会看到 fps 下降 1-3 帧，尤其是当创建的节点超过 +15 个时。所以我认为池节点对于良好的性能至关重要。

这是我到目前为止的尝试:

创建全局数组变量:

var smallPlArray = [SKSpriteNode]() 
var midPlArray = [SKSpriteNode]() 
var bigPlArray = [SKSpriteNode]() 
var groundPlArray = [SKSpriteNode]()

// small, middle and big refers to the platforms size's not the array size

创建 SKSpritenode 并将它们添加到数组的函数:

// Gets called in didMoveToView

func fillSpriteArrays() {

    var smallPlCount:Int = 0
    var groundPlCount:Int = 0

    for _ in 0..<10 {

        let smallPlatform = SKSpriteNode(texture: platform_Small_Texture)
        smallPlatform.zPosition = 4
        smallPlatform.size = CGSize(width: 509.5, height: 55.8)
        smallPlatform.isHidden = true

        smallPlatform.physicsBody = SKPhysicsBody(rectangleOf: smallPlatform.size)
        smallPlatform.physicsBody?.categoryBitMask = PhysicsCatagory.platforms
        smallPlatform.physicsBody?.contactTestBitMask = 0
        smallPlatform.physicsBody?.isDynamic = false
        smallPlatform.physicsBody?.affectedByGravity = false
        smallPlatform.physicsBody?.friction = 0.0
        smallPlatform.physicsBody?.restitution = 0.0

        smallPlArray.append(smallPlatform)
        groundPair.addChild(smallPlArray[smallPlCount])

        smallPlCount += 1
    }


    for _ in 0..<10 {

        let groundPlatform = SKSpriteNode(texture: middle_Ground_Platform_Texture)
        groundPlatform.zPosition = 4
        groundPlatform.size = CGSize(width: 898.4, height: 255.5)
        groundPlatform.isHidden = true

        groundPlatform.physicsBody = SKPhysicsBody(rectangleOf: groundPlatform.size)
        groundPlatform.physicsBody?.categoryBitMask = PhysicsCatagory.groundPlatform
        groundPlatform.physicsBody?.contactTestBitMask = 0
        groundPlatform.physicsBody?.isDynamic = false
        groundPlatform.physicsBody?.affectedByGravity = false
        groundPlatform.physicsBody?.friction = 0.0
        groundPlatform.physicsBody?.restitution = 0.0

        groundPlArray.append(groundPlatform)
        groundPair.addChild(groundPlArray[groundPlCount])

        groundPlCount += 1
    }

 // Same for the other array's...
}

尝试从数组中获取 SKSpritenodes 并使用它们:

func platforms1() {

    let ground1 = groundPlArray[0]
    ground1.position = CGPoint(x: 3800, y: 375)
    ground1.isHidden = false

    let ground2 = groundPlArray[1]
    ground2.position = CGPoint(x: 7000, y: 375)
    ground2.isHidden = false

    let smallPl1 = smallPlArray[0]
    smallPl1.position = CGPoint(x: 4350, y: 720)
    smallPl1.isHidden = false

    let smallPl2 = smallPlArray[1]
    smallPl1.position = CGPoint(x: 5600, y: 720)
    smallPl2.isHidden = false

// Other nodes not in connection with the array's

    createSpring(position: CGPoint(x: 2500, y: 337))
    createCrate(position: CGPoint(x: 5000, y: 350))
    createCrate(position: CGPoint(x: 5600, y: 350))
    createJelly(position: CGPoint(x: 7000, y: 330))
    createRoundWoodSpike(position: CGPoint(x: 7300, y: 550))
    createPlatformEndNode(position: CGPoint(x: 8500, y: 788))
    createDiamond(position: CGPoint(x: 2800, y: 800))
    createDiamond(position: CGPoint(x: 2880, y: 800))
    createDiamond(position: CGPoint(x: 4070, y: 575))
 }

所以，这就是我失败的地方。不知何故只有来自 smallPlArray 的一个节点被显示，但在 groundPlArray 上所有两个节点都被显示。这些节点的父节点 (groundPair) 被移动，当某个点通过时(屏幕上没有节点)，父节点位置被重置并且 platforms1() 被再次调用并且节点再次出现。这适用于所有其他节点，如 Spring 、 crate 等，但阵列中的节点不会再次返回。仅当第一次调用 platforms1() 时，数组中 4 个节点中的 3 个才会出现。显然我在这方面失败了。我究竟做错了什么？是否有另一种或更好的汇集方式？不幸的是，我对阵列的经验不多，但如果有必要，我可以学习。

编辑

调用代码的方式如下:

    func diceRollPlatforms() {

    platformSpawnCount = 0

    let shuffled = GKRandomDistribution(lowestValue: 1, highestValue: 15)
    var number = shuffled.nextInt()

// Repeat one platform sequence over and over instead of a random int
    if number != 1 || number == 1 {
        platforms1() 
}

然后:

func platforms_1() {

    shouldMovePlatforms = true // Just triggers the moving of groundPair in update

    createSpring(position: CGPoint(x: 2500, y: 337))
    createCrate(position: CGPoint(x: 5000, y: 350))
    createCrate(position: CGPoint(x: 5600, y: 350))
    createJelly(position: CGPoint(x: 7000, y: 330))
    createRoundWoodSpike(position: CGPoint(x: 7300, y: 550))
    createPlatformEndNode(position: CGPoint(x: 8500, y: 788)) // On contact with the player,groundPair(parent) gets reseted and diceRollPlatforms() is called again. 
//BUT the children are not removed. Children like spring etc are removed with the physics engine when they contact a node
//on the near outside left of the screen which does not affect the platforms, only obstacles like said before spring, crate...


    let ground1 = groundPlArray[0]
    ground1.position = CGPoint(x: 3800, y: 375)
    ground1.isHidden = false


    let ground2 = groundPlArray[1]
    ground2.position = CGPoint(x: 7000, y: 375)
    ground2.isHidden = false

    let smallPl1 = smallPlArray[0]
    smallPl1.position = CGPoint(x: 4350, y: 720)
    smallPl1.isHidden = false

    let smallPl2 = smallPlArray[1]
    smallPl2.position = CGPoint(x: 5600, y: 720)
    smallPl2.isHidden = false

// How the array is being filled is already explained above
    }

createSpring等函数内部，基本都是一样的:

func createSpring(position: CGPoint) {
    let spring = SKSpriteNode(texture: spring_Texture3)
    spring.size = CGSize(width: 230.9, height: 151.0)
    spring.zPosition = 4
    spring.position = position

    spring.physicsBody = SKPhysicsBody(rectangleOf: spring.size)
    spring.physicsBody?.categoryBitMask = PhysicsCatagory.spring
    spring.physicsBody?.contactTestBitMask = 0
    spring.physicsBody?.isDynamic = false
    spring.physicsBody?.affectedByGravity = false
    spring.physicsBody?.friction = 0.0
    spring.physicsBody?.restitution = 0.0

    groundPair.addChild(spring)
}

@Knight0fDragon 如果有什么不清楚的地方请告诉我。

第二次编辑

    func createPlatformEndNode(position: CGPoint) {
    let platformEndNode = SKSpriteNode()
    platformEndNode.position = position
    platformEndNode.zPosition = 4
    platformEndNode.size = CGSize(width: 30, height: 1536)

    platformEndNode.physicsBody = SKPhysicsBody(rectangleOf: platformEndNode.size)
    platformEndNode.physicsBody?.categoryBitMask = PhysicsCatagory.platformEndNode
    platformEndNode.physicsBody?.contactTestBitMask = PhysicsCatagory.platforms | PhysicsCatagory.obstacle | PhysicsCatagory.obstacleDeathObject | PhysicsCatagory.enemy | PhysicsCatagory.collidablePlatforms | PhysicsCatagory.spring | PhysicsCatagory.breakAbleObstacle | PhysicsCatagory.triggerEnemyNode | PhysicsCatagory.platformEndNode | PhysicsCatagory.groundPlatform | PhysicsCatagory.collidableGroundPlatform | PhysicsCatagory.breakAblePlatformsNotcollidable | PhysicsCatagory.breakAblePlatforms | PhysicsCatagory.cherry
    platformEndNode.physicsBody?.isDynamic = false
    platformEndNode.physicsBody?.affectedByGravity = false

    groundPair.addChild(platformEndNode)
}

func didEnd(_ contact: SKPhysicsContact) {
        // Check if contact ended with platformEndNode
    if firstBody.categoryBitMask == PhysicsCatagory.platformEndNode && secondBody.categoryBitMask == PhysicsCatagory.dragon || firstBody.categoryBitMask == PhysicsCatagory.dragon && secondBody.categoryBitMask == PhysicsCatagory.platformEndNode {
        spawnPlatformsAgain()

        if firstBody.categoryBitMask == PhysicsCatagory.platformEndNode {
            firstBody.node!.removeFromParent()
        } else {
            secondBody.node!.removeFromParent()
        }
    }
        // Check if contact ended with platformStartNode
    if firstBody.categoryBitMask == PhysicsCatagory.triggerPlatformStartNode && secondBody.categoryBitMask == PhysicsCatagory.dragon || firstBody.categoryBitMask == PhysicsCatagory.dragon && secondBody.categoryBitMask == PhysicsCatagory.triggerPlatformStartNode {
        if firstBody.categoryBitMask == PhysicsCatagory.triggerPlatformStartNode {
            firstBody.node!.removeFromParent()
        } else {
            secondBody.node!.removeFromParent()
        }
        if platformSpawnCount == 0 { platformSpawnCount = 1; prepareGroundPair(); diceRollPlatforms() }
    }
}
     func spawnPlatformsAgain() {

    if !wasWaterHere {

        timeToIncreaseGameSpeed = true; platformSpawnCount = 0
        prepareForNextPlatforms(); increaseGameSpeed()
        if addRollingWoodEnemy == true { spawnRollingWoodEnemyAfterPlatforms() }
        isCollidingWithBreakAblePlatforms = false

        createPlatformStartNode(position: CGPoint(x: 1024, y: 768))

    } else {

        timeToIncreaseGameSpeed = true; platformSpawnCount = 0
        prepareForNextPlatforms(); increaseGameSpeed()
        if addRollingWoodEnemy == true { spawnRollingWoodEnemyAfterPlatforms() }
        isCollidingWithBreakAblePlatforms = false

        wasWaterHere = false
        bigGroundAndWaterTileNode.removeAllChildren()
        bigGroundAndWaterTileNode.removeAllActions()
        bigGroundAndWaterTileNode.position = CGPoint(x: 0, y: 0)
        bigGroundAndWaterTileNode.isHidden = true

        createPlatformStartNode(position: CGPoint(x: 1536, y: 768))
    }
}
    func prepareGroundPair() {

    shouldMovePlatforms = false
    groundPair.position.x = 0
}

func prepareForNextPlatforms() {

    groundPair.position.x = 0

    enemyParent.removeAllChildren(); enemyParent.removeAllActions()
    enemyParent.position.x = 0

}

第三次编辑

groundPair 的移动:

    // Runs in Update
func moveWorldObjects() {
            if shouldMovePlatforms == true {
                groundPair.position = CGPoint(x: groundPair.position.x - CGFloat(xPosition), y: groundPair.position.y)
            }

Answer 1

是的，有可能，您的问题是复制和粘贴失败。你从来没有设置 smallPl2 的位置，而是你不小心设置了两次 smallPl1。

不过，我会完全避免这种方法。只有当你受到严重的性能限制时，我才会建议做这样的池(你不是，你的代码效率不高)。创建一个新对象每次都会让您重新开始，因此您无需担心重置节点的属性。

相反，回到您正在做的事情，每次都创建一个新平台。

不过这一次，创建一系列在后台线程中排队的保留节点以实现您的目标。然后，您可以在更新或更新阶段的 didFinish 部分将它们添加到您的场景中，以避免任何冲突。

这里是一个如何创建一些保留节点的例子

var reservedNodes = SKNode()  //This SKNode is going to house all of our reserves,  I prefer it over [SKNode]().

func spawnReserves()
{
       if reservedNodes.children.count < 5
       {
          DispatchQueue.global(qos: .background).async 
          { 
            [weak self] in 
            //before this point if self does not exist then safely exit
            guard let strongSelf = self else {return}
           //beyond this point we do not want self to die                
            let node = strongSelf.createNode()
            DispatchQueue.main.async 
            {
              [weak self] in 
              //before this point if self does not exist then safely exit
              //now because we use `node`,  strongSelf should not even be needed, since the background thread should be retained, but I threw it in just in case
              guard let strongSelf = self else {return}
              //beyond this point we do not want self to die
              //As long as reservedNodes is not added to the scene, this should not cause problems, never add it to the scene.
              strongSelf.reservedNodes.addChild(node)
            }
          }
       }

}


func update(currentTime: TimeInterval)
{
    //If I need nodes grab from reserve
    //what is nice about .first is the where feature, so you can say first(where:{$0.isKind(of:PlatformNode)})
    if let node = reserveNodes.children.first
    {
      node.moveToParent(self) //this will remove them from the array for us
    }
}

func didFinishUpdate()
{
   spawnReserves()
}

现在有了子类化，您可以更进一步，检查何时移除子节点以生成新节点，这样您就可以始终创建节点，但我将把更高级的工作留给您。这至少应该可以帮助您从概念上开始使用池