我在Swift写一个游戏。我有一个可以在屏幕上移动的播放器。我希望SpeedLines（动画）与玩家一起移动（直接在它上面）。此外，当我编译并运行我的项目时，有时SpeedLines不会显示在屏幕上。如果你能提供帮助，我将非常感激。我的代码：
func buildSpeedLines() {
let SpeedLinesAtlas = SKTextureAtlas(named: "SpeedLines")
var walkFrames: [SKTexture] = []
let numImages = SpeedLinesAtlas.textureNames.count
for i in 1...numImages {
let SpeedLinesName = "SpeedLines\(i)"
walkFrames.append(SpeedLinesAtlas.textureNamed(SpeedLinesName))
}
SpeedLineFrames = walkFrames
let firstFrameTexture = SpeedLineFrames[0]
SpeedLines = SKSpriteNode(texture: firstFrameTexture)
SpeedLines.setScale(1.2)
addChild(SpeedLines)
}
func animateSpeedLines() {
SpeedLines.run(SKAction.repeatForever(
SKAction.animate(with: SpeedLineFrames,
timePerFrame: 0.4,
resize: false,
restore: true)),
withKey:"SpeedLinesBehindFallingObject")
}
func startGame(){
currentGameState = gameState.inGame
let deleteAction = SKAction.removeFromParent()
let moveDroppableOntoScreenAction1 = SKAction.moveBy(x: 0, y: -self.size.height * 0.1, duration: 0.025)
let moveDroppableOntoScreenAction2 = SKAction.moveBy(x: 0, y: -self.size.height * 0.09, duration: 0.05)
let moveDroppableOntoScreenAction3 = SKAction.moveBy(x: 0, y: -self.size.height * 0.08, duration: 0.075)
let moveDroppableOntoScreenAction4 = SKAction.moveBy(x: 0, y: -self.size.height * 0.07, duration: 0.1)
let moveDroppableOntoScreenAction5 = SKAction.moveBy(x: 0, y: -self.size.height * 0.06, duration: 0.125)
let moveDroppableOntoScreenAction6 = SKAction.moveBy(x: 0, y: -self.size.height * 0.05, duration: 0.15)
let moveDroppableOntoScreenAction7 = SKAction.moveBy(x: 0, y: -self.size.height * 0.04, duration: 0.175)
let moveDroppableOntoScreenAction8 = SKAction.moveBy(x: 0, y: -self.size.height * 0.03, duration: 0.2)
let moveDroppableOntoScreenAction9 = SKAction.moveBy(x: 0, y: -self.size.height * 0.02, duration: 0.225)
let moveDroppableOntoScreenAction10 = SKAction.moveBy(x: 0, y: -self.size.height * 0.01, duration: 0.25)
let startGameSequence = SKAction.sequence([moveDroppableOntoScreenAction1, moveDroppableOntoScreenAction2, moveDroppableOntoScreenAction3, moveDroppableOntoScreenAction4, moveDroppableOntoScreenAction5, moveDroppableOntoScreenAction6, moveDroppableOntoScreenAction7, moveDroppableOntoScreenAction8, moveDroppableOntoScreenAction9, moveDroppableOntoScreenAction10])
buildSpeedLines()
animateSpeedLines()
let location = CGPoint(x: player.position.x, y: player.position.y)
player.run(startGameSequence)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if currentGameState == gameState.preGame {
startGame()
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
}