How to randomly pick a node at a position? - swift

Question

I have five different colored circles, each called in the same function but with different physicsBodies and names. I would like them all to move upwards from the bottom of the screen with only one node on the screen at a time from one set position (i.e, CGPointMake(100, -500)) Like after a randomly colored node is generated, after 4 seconds a different randomly picked one will appear?
Is there a way to keep all of them individually identified and do this?
Code:
func circles() {
let sprites = SKSpriteNode(imageNamed: "Circle1")
sprites.position = CGPointMake(45, -200)
sprites.physicsBody = SKPhysicsBody(circleOfRadius: 40)
sprites.physicsBody?.dynamic = true
sprites.physicsBody?.affectedByGravity = false
sprites.physicsBody?.categoryBitMask = BodyType.player.rawValue
sprites.physicsBody?.contactTestBitMask = BodyType.enemy.rawValue | BodyType.other.rawValue | BodyType.seven.rawValue | BodyType.nine.rawValue | BodyType.five.rawValue
sprites.size = CGSizeMake(45, 45)
all.addChild(sprites)
let sprite2 = SKSpriteNode(imageNamed: "Circle2")
sprite2.position = CGPointMake(60, -750)
sprite2.physicsBody = SKPhysicsBody(circleOfRadius: 40)
sprite2.physicsBody?.categoryBitMask = BodyType.eight.rawValue
sprite2.physicsBody?.contactTestBitMask = BodyType.nine.rawValue | BodyType.other.rawValue | BodyType.five.rawValue | BodyType.enemy.rawValue | BodyType.seven.rawValue
sprite2.physicsBody?.dynamic = true
sprite2.physicsBody?.affectedByGravity = false
sprite2.size = CGSizeMake(45, 45)
addChild(sprite2)
let sprite3 = SKSpriteNode(imageNamed: "circle3")
sprite3.position = CGPointMake(100, -1200)
sprite3.physicsBody = SKPhysicsBody(circleOfRadius: 40)
sprite3.physicsBody?.categoryBitMask = BodyType.six.rawValue
sprite3.physicsBody?.contactTestBitMask = BodyType.seven.rawValue | BodyType.other.rawValue | BodyType.five.rawValue | BodyType.enemy.rawValue | BodyType.nine.rawValue
sprite3.physicsBody?.dynamic = true
sprite3.physicsBody?.affectedByGravity = false
sprite3.size = CGSizeMake(45, 45)
addChild(sprite3)
let sprite4 = SKSpriteNode(imageNamed: "Circle4")
sprite4.position = CGPointMake(150, -1400)
sprite4.physicsBody = SKPhysicsBody(circleOfRadius: 40)
sprite4.physicsBody?.categoryBitMask = BodyType.ground.rawValue
sprite4.physicsBody?.contactTestBitMask = BodyType.other.rawValue | BodyType.player.rawValue | BodyType.five.rawValue | BodyType.enemy.rawValue | BodyType.seven.rawValue
sprite4.physicsBody?.dynamic = true
sprite4.physicsBody?.affectedByGravity = false
sprite4.size = CGSizeMake(45, 45)
addChild(sprite4)
let sprite5 = SKSpriteNode(imageNamed: "Circle5")
sprite5.position = CGPointMake(200, -850)
sprite5.physicsBody = SKPhysicsBody(circleOfRadius: 40)
sprite5.physicsBody?.categoryBitMask = BodyType.ya.rawValue
sprite5.physicsBody?.contactTestBitMask = BodyType.five.rawValue | BodyType.player.rawValue | BodyType.other.rawValue | BodyType.seven.rawValue | BodyType.nine.rawValue
sprite5.physicsBody?.dynamic = true
sprite5.physicsBody?.affectedByGravity = false
sprite5.size = CGSizeMake(45, 45)
addChild(sprite5)
}
Help much appreciated.

Answer 1

You can use the name property of SKNode.
From the documentation:
Used to assign a name to a node for later reference. When choosing a
name for a node, you should decide whether each node gets a unique
name or whether some nodes will share a common name. If you give the
node a unique name, you can find the node later by calling the
childNodeWithName: method. If a name is shared by multiple nodes, the
name usually means that these are all a similar object type in your
game. In this case, you can iterate over those objects by calling the
enumerateChildNodesWithName:usingBlock: method.