Swift 3 - Background loop not working properly - swift

Question

I am trying to make a Flappy Bird like game and have to make my background loop infinitely. I found some tutorials online but it is just not working for me and I can't figure out why.
This is my code so far
var Background = SKSpriteNode()
var txtBG = SKTexture(imageNamed: "Background")
var txtLand = SKTexture(imageNamed: "Ground")
var Ground = SKSpriteNode()
var moving:SKNode!
// Cena
override func didMove(to view: SKView) {
scene?.anchorPoint = CGPoint(x: 0, y: 0)
moving = SKNode()
self.addChild(moving)
//Ground
Ground = SKSpriteNode(texture: txtLand)
Ground.position = CGPoint(x:0, y: txtLand.size().height * 1.3)
Ground.setScale(2.5)
self.addChild(Ground)
//Background
Background = SKSpriteNode(texture: txtBG)
Background.setScale(2.0)
Background.position = CGPoint(x: self.size.width, y: txtLand.size().height * 5.2 )
let BGmove = SKAction.moveBy(x: -txtBG.size().width * 2.0, y: txtLand.size().height * 5.2 , duration: TimeInterval(15))
let BGRepo = SKAction.moveBy(x: txtBG.size().width * 2.0, y: txtLand.size().height * 5.2, duration: 0.0)
let BGLoop = SKAction.repeatForever(SKAction.sequence([BGmove,BGRepo]))
for i in 0 ..< 2 + Int(self.frame.size.width / ( txtBG.size().width * 2 )) {
let i = CGFloat(i)
Background = SKSpriteNode(texture: txtBG)
Background.setScale(2.0)
Background.position = CGPoint(x:txtBG.size().width/2 + txtBG.size().width * i * 2.0, y: txtLand.size().height * 5.2)
Background.run(BGLoop)
self.addChild(Background)
}
What happens is the background starts moving horizontally but also moving upwards and I don't understand why.
Any help will be much appreciated!

Answer 1

Your Background Move actions have the background moving by x and by y. If you want to use SKAction.moveBy(x: CGFloat, y: CGFloat, duration: TimeInterval) then set y to 0 or you can use SKAction.moveTo(x: CGFloat, duration: TimeInterval) to only move the x value.