Bullet Firing In Direction Of Tap - swift

Question

So far, my app has a big ball in the middle and a small ball in the middle also. I would like to be able to tap anywhere on the screen and the small ball shoots in that direction. I've heard people say about creating vectors but I can't seem to get these working in swift 3. I am a beginner so sorry about a stupid question!
Here is my code:
var mainBall = SKSpriteNode(imageNamed: "Ball")
override func didMove(to view: SKView) {
mainBall.size = CGSize(width: 300, height: 300)
mainBall.position = CGPoint(x: frame.width / 2, y: frame.height / 2)
self.addChild(mainBall)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
let position = touch.location(in: self)
print(position.x)
print(position.y)
}
for touch in (touches) {
touch.location(in: self)
let smallBall = SKSpriteNode(imageNamed: "Ball")
smallBall.position = mainBall.position
smallBall.size = CGSize(width: 100, height: 100)
smallBall.physicsBody = SKPhysicsBody(circleOfRadius: smallBall.size.width / 2)
smallBall.physicsBody?.affectedByGravity = false
self.addChild(smallBall)
}
}

Answer 1

You can use actions to animate SKSprideNodes:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
guard let touch = touches.first else {
return
}
let newPosition = touch.location(in: self)
...
//assuming self.smallBall exists and is visible already:
[self.smallBall runAction:[SKAction moveTo:newPosition duration:1.0]];
}