Apple Game Frameworks and Technologies

Move the Player Using Physics

Using physics to move bodies is a quick and effective way to build a controller. To move the player using physics and the on-screen controller, you need to act on certain touch events.

Open the GameScene.swift file and update the touchDown(:atPoint) method:

func touchDown(atPoint pos : CGPoint) {
  let nodeAtPoint = atPoint(pos)
  if let touchedNode = nodeAtPoint as? SKSpriteNode {
    if touchedNode.name?.starts(with: "controller_") == true {
      let direction = touchedNode.name?.replacingOccurrences(
        of: "controller_", with: "")
      player?.move(Direction(rawValue: direction ?? "stop")!)
    }
  }
}

Here, you’re checking to see which node was touched using the prefix of the ...