swift - SceneKit切换场景内存泄漏

Question

我有两个空白场景对象，没有任何节点和摄像机:

func setupScenes() {
   scnView = SCNView(frame: self.view.frame)
   self.view.addSubview(scnView)

   gameScene = SCNScene(named: "/MrPig.scnassets/GameScene.scn")
   splashScene = SCNScene(named: "/MrPig.scnassets/SplashScene.scn")
   scnView.scene = splashScene
}

显示每个场景的两种方法:

func startSplash() {
    gameScene.isPaused = true
    let transition = SKTransition.doorsOpenVertical(withDuration: 1.0)
    scnView.present(splashScene, with: transition, incomingPointOfView: nil, completionHandler: {
      self.gameState = .tapToPlay
      self.setupSounds()
      self.splashScene.isPaused = false
    })
  }

  func startGame() {
    splashScene.isPaused = true
    let transition = SKTransition.doorsOpenVertical(withDuration: 1.0)
    scnView.present(gameScene, with: transition, incomingPointOfView: nil, completionHandler: {
      self.gameState = .playing
      self.setupSounds()
      self.gameScene.isPaused = false
    })
  }

以及用于在场景之间切换的触摸手势:

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        if gameState == .tapToPlay {
            startGame()
        } else {
            startSplash()
        }
    }

每次我触摸屏幕时，屏幕上都会出现第一个或第二个场景，我已经习惯了加上 ~80Mb 的 RAM。10 次接触后，已使用 500MB RAM。

我不明白为什么会发生这种情况？

Answer 1

代码中明显的问题是，每次调用 startGame() 和 startSplash() 方法时，带有闭包的嵌套函数都会捕获具有强引用的“ self ”。

Some info about strong and weak references and ARC.

首先，您应该执行以下操作:

func startSplash() {
    gameScene.isPaused = true
    let transition = SKTransition.doorsOpenVertical(withDuration: 1.0)
    scnView.present(splashScene, with: transition, incomingPointOfView: nil, completionHandler: { [weak self] in
        guard let self = self else { return }
        self.gameState = .tapToPlay
        self.setupSounds()
        self.splashScene.isPaused = false
    })
}

func startGame() {
    splashScene.isPaused = true
    let transition = SKTransition.doorsOpenVertical(withDuration: 1.0)
    scnView.present(gameScene, with: transition, incomingPointOfView: nil, completionHandler: { [weak self] in
        guard let self = self else { return }
        self.gameState = .playing
        self.setupSounds()
        self.gameScene.isPaused = false
    })
}

其次，尽量不要使用touchesBegan方法，它可能会导致一些副作用。

希望对你有帮助!