Coud someone help me pout with this please? I have used this on the box object as well to get those notifications "box.physicsBody!.contactTestBitMask = box.physicsBody!.collisionBitMask" and the same methods but the ball just bounces off the boxes.

What does your collisionBetween(ball:object:) function look like?

Hi and thank you for the reply, this is what I have so far, but I still don't get it why is not removing the node from the game when the ball hits.

func collisionBetween(ball: SKNode, object: SKNode) { if object.name == "good" { // green slot destroy(ball: ball) score += 1 usedBalls += 1 } else if object.name == "bad" { // red slot destroy(ball: ball) // the ball will be removed once drops into a green or red slot score -= 1

    }

}

func boxandballCollision(box: SKNode, ball: SKNode) {
    if ball.name == "ball" {
    destroyObject(box: box)

    }
}

func destroyObject(box: SKNode) {
    if let fireParticles = SKEmitterNode(fileNamed: "FireParticles") {
        fireParticles.position = box.position
        addChild(fireParticles)
    }

    box.removeFromParent() // box should be removed when a ball will hit it
}

func destroy(ball: SKNode) {
    if let fireParticles = SKEmitterNode(fileNamed: "FireParticles") {
        fireParticles.position = ball.position
        addChild(fireParticles)
    }

    ball.removeFromParent() // ball object is removed from scene when hits a slot

}

func didBegin(_ contact: SKPhysicsContact) {
    guard let nodeA = contact.bodyA.node else { return }
    guard let nodeB = contact.bodyB.node else { return }

    if nodeA.name == "ball" {
        collisionBetween(ball: nodeA, object: nodeB)
    } else if nodeB.name == "ball" {
        collisionBetween(ball: nodeB, object: nodeA)

        }
    }

func begin(_ contact: SKPhysicsContact) {
    guard let nodeA = contact.bodyA.node else { return }
    guard let nodeB = contact.bodyB.node else { return }

    if nodeA.name == "box" {
        boxandballCollision(box: nodeA, ball: nodeB)
    } else if nodeB.name == "box" {
        boxandballCollision(box: nodeB, ball: nodeA)
      }
   }

I have declared another method for box and ball collision

The problem is this function:

func begin(_ contact: SKPhysicsContact) {
    guard let nodeA = contact.bodyA.node else { return }
    guard let nodeB = contact.bodyB.node else { return }

    if nodeA.name == "box" {
        boxandballCollision(box: nodeA, ball: nodeB)
    } else if nodeB.name == "box" {
        boxandballCollision(box: nodeB, ball: nodeA)
      }
   }

It never gets called. You are probably thinking it should be called just like didBegin(_:) is, but that function is part of the SKPhysicsContactDelegate protocol and gets called by the system. The system has no way of knowing to call your new begin(_:) function.

You need to put your logic into didBegin(_:) and get rid of your begin(_:) function. You don't really need a separate function if one of the objects involved in the collision is a box.

Here, for instance, is the relevant code from my Project 11:

    func didBegin(_ contact: SKPhysicsContact) {
        guard let nodeA = contact.bodyA.node else { return }
        guard let nodeB = contact.bodyB.node else { return }

        if nodeA.name == "ball" {
            collisionBetween(ball: nodeA, object: nodeB)
        } else if contact.bodyB.node?.name == "ball" {
            collisionBetween(ball: nodeB, object: nodeA)
        }
    }

    func collisionBetween(ball: SKNode, object: SKNode) {
        if object.name == "good" {
            score += 1
            ballCount += 1
            destroy(ball: ball)
        } else if object.name == "bad" {
            score -= 1
            destroy(ball: ball)
        } else if object.name == "box" {
            //we have an obstacle object
            object.removeFromParent()
        }
    }

See how we already know that one of the objects involved is a ball, so all we really need to do in collisionBetween(ball:object:) is check what the other object is.

And please, when posting code to these forums, place three backticks ``` on the line before your code and three backticks ``` on the line after your code so that it will be formatted properly. You can also highlight an entire codeblock and click the </> button on the toolbar to wrap the block for you.

This makes it far easier to read and also makes it easier for other posters to copy/paste the code in order to test solutions and such.

Doing this will ensure that you end up with something like this:

func printSomething(_ thing: String?) {
    if let thing = thing {
        print(thing)
    } else {
        print("nothing there")
    }
}

instead of this:

func printSomething(_ thing: String?) { if let thing = thing { print(thing) } else { print("nothing there") } }

Okay thank you! That makes sense, I was thinking if I have the same parameter for that seperate method it might pick up that function, just tried your solution which works great, I just called that distructionObject(box:) method in "collisionBetween" method to apply that fire effect. I will put those backticks there, I was looking how to wrap my block of code. Thanks again!