Contain a sprite node within the screen/view - ios

Question

I have a sprite node which moves left to right with user touch.
However currently it will exit the screen, I want to add a node either side so if the sprite node touches the node on either side it hugs it and remains there until user touch to make it travel the opposite direction.
This is what I thought of doing but it isn't working currently.
let shipTexture = SKTexture(imageNamed: "ship.png")
ship = SKSpriteNode(texture: shipTexture)
ship.position = CGPoint(x: self.frame.midX, y: self.frame.midY)
ship.zPosition = 3
ship.physicsBody = SKPhysicsBody(rectangleOf: CGSize(width: 30, height: 100))
ship.physicsBody!.isDynamic = true
ship.physicsBody?.collisionBitMask = 0b1
ship.physicsBody?.contactTestBitMask = 0b1
ship.physicsBody!.collisionBitMask = 0b1
ship.physicsBody?.affectedByGravity = false
self.addChild(ship)
let side = SKNode()
side.position = CGPoint(x: self.frame.width / 2, y: self.frame.midY)
side.physicsBody = SKPhysicsBody(edgeLoopFrom: CGRect(x: -240, y: -160, width: 480, height: 320))
side.physicsBody!.isDynamic = false
side.physicsBody?.collisionBitMask = 0b1
side.physicsBody?.contactTestBitMask = 0b1
side.physicsBody!.collisionBitMask = 0b1
self.addChild(side)
func didBegin(_ contact: SKPhysicsContact) {
print("Collision")
}
}
//var moveLeft = SKAction.moveBy(x: 800, y: 0, duration: 2)
//frame.size.width
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
ship.removeAllActions()
switch direction ?? .left {
case .left:
ship.run(SKAction.moveBy(x: -frame.size.width, y: 0, duration: 3))
case .right:
ship.run(SKAction.moveBy(x: frame.size.width, y: 0, duration: 3))
}
direction = direction == nil || direction == .right ? .left : .right
}

Answer 1

I got it. The reason is - you use action to move your node, but should use physics - force and impulse
Try this one:
import SpriteKit
import GameplayKit
var ship = SKSpriteNode()
var bg = SKSpriteNode()
class GameScene: SKScene, SKPhysicsContactDelegate {
override func didMove(to view: SKView) {
let bgTexture = SKTexture(imageNamed: "bg.png")
let moveBGanimation = SKAction.move(by: CGVector(dx: 0, dy: -bgTexture.size().height), duration: 4)
let shiftBGAnimation = SKAction.move(by: CGVector(dx: 0, dy: bgTexture.size().height), duration: 0)
let moveBGForever = SKAction.repeatForever(SKAction.sequence([moveBGanimation, shiftBGAnimation]))
var i: CGFloat = 0
while i < 3 {
bg = SKSpriteNode(texture: bgTexture)
bg.position = CGPoint(x: self.frame.midX, y: bgTexture.size().height * i)
bg.size.width = self.frame.width
bg.run(moveBGForever)
self.addChild(bg)
i += 1
}
let shipTexture = SKTexture(imageNamed: "ship.png")
ship = SKSpriteNode(texture: shipTexture)
ship.position = CGPoint(x: self.frame.midX, y: self.frame.midY)
ship.zPosition = 3
ship.physicsBody = SKPhysicsBody(rectangleOf: CGSize(width: 30, height: 100))
ship.physicsBody!.isDynamic = true
ship.physicsBody?.collisionBitMask = 0b1
ship.physicsBody?.contactTestBitMask = 0b1
ship.physicsBody!.categoryBitMask = 0b1
ship.physicsBody?.affectedByGravity = false
self.addChild(ship)
let side = SKNode()
side.position = CGPoint(x: 0, y: 0)
side.physicsBody = SKPhysicsBody(edgeLoopFrom: CGRect(x: -self.frame.width/2, y: -self.frame.height/2, width: self.frame.width, height: self.frame.height))
side.physicsBody!.isDynamic = false
side.physicsBody?.collisionBitMask = 0b1
side.physicsBody?.contactTestBitMask = 0b1
side.physicsBody!.categoryBitMask = 0b1
self.addChild(side)
self.physicsWorld.contactDelegate = self
func didBegin(_ contact: SKPhysicsContact) {
print("Collision")
}
}
//var moveLeft = SKAction.moveBy(x: 800, y: 0, duration: 2)
//frame.size.width
enum Direction: Int {
case left = 0
case right
}
var direction: Direction?
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
ship.removeAllActions()
switch direction ?? .left {
case .left:
ship.physicsBody?.applyImpulse(CGVector(dx: -20, dy: 0))
//ship.run(SKAction.moveBy(x: -frame.size.width, y: 0, duration: 3))
case .right:
ship.physicsBody?.applyImpulse(CGVector(dx: 20, dy: 0))
//ship.run(SKAction.moveBy(x: frame.size.width, y: 0, duration: 3))
}
direction = direction == nil || direction == .right ? .left : .right
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
}
override func update(_ currentTime: TimeInterval) {
}
}