Hit Testing and Collision Detection - Beginning Swift Games Development for iOS - page 210

The one item you now need to add is the enemy node, which is created just like the space-
men node. Open the GameViewController class and create a variable for the en-
emyNode right after spacemanNode : var enemyNode: SCNNode .
You will follow the same pattern as the spacemanNode , so now you need to create an
SCNNode to assign to this class-level variable. In the createMainScene() method,
you will call the setupEnemy() method, enemyNode
= setupEnemy(mainScene) . You will create this method next, so don't worry
about the error at this time.
It is now time to get rid of that error about a missing method. Right after your
setupSpaceMan() , you will create the new setupEnemy() , as Listing 14-5 shows.
Listing 14-5 . setupEnemy( )
func setupEnemy(scene:SCNScene) -> SCNNode {
var enemyScene = SCNScene(named: "art.scnassets/
Enemy.dae")
var enemyNode
= enemyScene!.rootNode.childNodeWithName("enemy",
recursively: false)
enemyNode!.name = "enemy"
enemyNode!.position = SCNVector3(x: 40, y: 10, z: 30)
enemyNode!.rotation = SCNVector4(x: 0, y: 1, z: 0, w:
Float(M_PI))
scene.rootNode.addChildNode(enemyNode!)
return enemyNode!
}
Now you have the enemy out in the playing floor, so you can dive into the collision detec-
tion of the various items.
Collision Detection
Now that you have the hero moving around an assortment of moving objects, you need to
determine when your hero runs into something.