Border collision detection

Question

I'm making a game with Sprite Kit and I have the collision detection setup like this:

    ball.physicsBody?.categoryBitMask = ballCategory
    borderBody.physicsBody?.categoryBitMask = borderCategory

And the handler -didBeginContact() :

func didBeginContact(contact: SKPhysicsContact) {

    var firstBody = SKPhysicsBody()
    var secondBody = SKPhysicsBody()

    if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
        firstBody = contact.bodyA
        secondBody = contact.bodyB
    }else {
        firstBody = contact.bodyB
        secondBody = contact.bodyA
    }

    if firstBody.categoryBitMask == ballCategory && secondBody.categoryBitMask == borderCategory {
        print("You Lose!")
    }

}

I also have this line to set the contact delegate:

self.physicsWorld.contactDelegate = self

But when I run the game, the collision is not detected and nothing happens. What is wrong?

Answer 1

See the documentation here . You need to set the contactTestBitMask if you want to receive contact/intersection notifications. Unlike collisionBitMask whose default value is 0xFFFFFFFF , the default value for contactTestBitMask is 0x00000000 .