For adding touch interactivity, we will use the touchesBegan function similar to how we have always used it in SpriteKit. So, here we get the location of the touch and name of the sprite under the touch location. If the sprite name is jumpBtn and the gameOver Boolean is false, then we call the heroJump function in the gameScene class. If gameOver is true and if the play button is clicked, then we call the startGame function in the SceneKit class.
So, add the function as follows to detect touches:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
/* Called when a touch begins */
for touch: AnyObject in touches {
let location = touch.locationInNode(self)
let _node:SKNode = self.nodeAtPoint(location);
if(_gameScene.gameOver == false){
if(_node.name == "jumpBtn"){
_gameScene.heroJump()
...