Swift Remove 1 node moving after collision

Question

I have nodes falling from the top of the screen every second or so. When the player (at the bottom of the screen) collides with a falling node I want that particular node to be removed from the screen but have the other continue to fall.

I thought calling node.removeFromParent() might do this or might remove all of the nodes but nothing is happening regardless.

Here is what I have:

Making the nodes fall:

func makeMete() {

    let meteTexture = SKTexture(imageNamed: "mete.png")
    let movementAmount = arc4random() % UInt32(self.frame.width)
    let meteOffset = CGFloat(movementAmount) - self.frame.width / 2
    let moveMete = SKAction.move(by: CGVector(dx: 0, dy: -2 * self.frame.height), duration: TimeInterval(self.frame.height / 300))

    let mete = SKSpriteNode(texture: meteTexture)
    mete.position = CGPoint(x: self.frame.midX + meteOffset, y: self.frame.midY + self.frame.height / 2)

    mete.physicsBody = SKPhysicsBody(circleOfRadius: meteTexture.size().height / 2)
    mete.physicsBody!.isDynamic = false
    mete.physicsBody!.contactTestBitMask = ColliderType.object.rawValue
    mete.physicsBody!.categoryBitMask = ColliderType.object.rawValue
    mete.physicsBody!.collisionBitMask = ColliderType.object.rawValue

    mete.run(moveMete)
    self.addChild(mete)




}

Detecting contact:

 func didBegin(_ contact: SKPhysicsContact) {

    if contact.bodyA.categoryBitMask == ColliderType.object.rawValue || contact.bodyB.categoryBitMask == ColliderType.object.rawValue {



    player.physicsBody!.velocity = CGVector(dx: 0, dy: 0)
    isUserInteractionEnabled = false

   mete.removeFromParent()


    }

.removeFromParent() seems to only work for me when there is one node on screen. Any more then it doesn't work.

The variable mete will always refer to the last mete created, not the one involved in the collision. So the removeFromParent will be working, it'll just be removing some other node that you may not have noticed. — Steve Ives
You might find your code clearer if you cal the mete's physics category ColliderType.mete. Also, are you sure that the contactTest and collision bit masks should be the same as the category? What is the category of the player? — Steve Ives

ymulki ymulki · Accepted Answer · 2017-03-20T22:50:04

If you use mete it references the actual object mete and I assume there are many metes on screen. Try referencing the actual node from the physics body and removing that from the parent.

Replace

if contact.bodyA.categoryBitMask == ColliderType.object.rawValue || contact.bodyB.categoryBitMask == ColliderType.object.rawValue {

player.physicsBody!.velocity = CGVector(dx: 0, dy: 0)
isUserInteractionEnabled = false
mete.removeFromParent()

}

With

if contact.bodyA.categoryBitMask == ColliderType.object.rawValue  {

        contact.bodyA.node?.removeFromParent()

}else if contact.bodyB.categoryBitMask == ColliderType.object.rawValue {
        contact.bodyB.node?.removeFromParent()
    }

The .node gives you access to the actual instance in question.

Good Luck!

Swift Remove 1 node moving after collision

1 Answers