Moving Background Swift SKSpriteKit

Question

I'm currently working on an application where I'm trying to set up a moving background. I have a transparent image full of clouds that I'm currently using. My problem is, how can I make it move more smoother? I've tried to play with the speeds but it still looks laggy. Any help would be a blessing.

Here's a video of what I got going. http://sendvid.com/78ggkzcj

And here's a picture of the cloud image. Cloud Image

Here's my code. What you think I should change or do differently?

class GameScene: SKScene {

    // Background
    let background = SKSpriteNode(texture:SKTexture(imageNamed: "background"))

    // Clouds
    var mainCloud = SKSpriteNode()
    var cloud1Next = SKSpriteNode()

    // Time of last frame
    var lastFrameTime : TimeInterval = 0

    // Time since last frame
    var deltaTime : TimeInterval = 0

    override func didMove(to view: SKView) {
        background.position = CGPoint(x: 0, y: 0)

        // Prepare the clouds sprites
        mainCloud = SKSpriteNode(texture:
            SKTexture(imageNamed: "cloudbg1"))
        mainCloud.position = CGPoint(x: 0, y: 0)

        cloud1Next = mainCloud.copy() as! SKSpriteNode
        cloud1Next.position =
            CGPoint(x: mainCloud.position.x + mainCloud.size.width,
                    y: mainCloud.position.y)

        // Add the sprites to the scene
        self.addChild(background)
        self.addChild(mainCloud)
        self.addChild(cloud1Next)
    }

    override func update(_ currentTime: TimeInterval) {
        // Called before each frame is rendered
        // First, update the delta time values:

        // If we don't have a last frame time value, this is the first frame,
        // so delta time will be zero.
        if lastFrameTime <= 0 {
            lastFrameTime = currentTime
        }

        // Update delta time
        deltaTime = currentTime - lastFrameTime

        // Set last frame time to current time
        lastFrameTime = currentTime

        // Next, move each of the four pairs of sprites.
        // Objects that should appear move slower than foreground objects.
        self.moveSprite(sprite: mainCloud, nextSprite:cloud1Next, speed:100)
    }

    // Move a pair of sprites leftward based on a speed value;
    // when either of the sprites goes off-screen, move it to the
    // right so that it appears to be seamless movement
    func moveSprite(sprite : SKSpriteNode,
                    nextSprite : SKSpriteNode, speed : Float) -> Void {
        var newPosition = CGPoint.zero

        // For both the sprite and its duplicate:
        for spriteToMove in [sprite, nextSprite] {

            // Shift the sprite leftward based on the speed
            newPosition = spriteToMove.position
            newPosition.x -= CGFloat(speed * Float(deltaTime))
            spriteToMove.position = newPosition

            // If this sprite is now offscreen (i.e., its rightmost edge is
            // farther left than the scene's leftmost edge):
            if spriteToMove.frame.maxX < self.frame.minX {

                // Shift it over so that it's now to the immediate right
                // of the other sprite.
                // This means that the two sprites are effectively
                // leap-frogging each other as they both move.
                spriteToMove.position =
                    CGPoint(x: spriteToMove.position.x +
                        spriteToMove.size.width * 2,
                            y: spriteToMove.position.y)
            }
        }
    }
}

Answer 1

Your code looks fine. You are getting low fps because you are running your game in the simulator. If you run on a real device, it should be smooth.