Adding a delegate to a Scene

GameScene.swift

class GameScene: SKScene, SKPhysicsContactDelegate{
  override func sceneDidLoad() {
    self.physicsWorld.contactDelegate = self
  }
  
  func didBegin(_ contact: SKPhysicsContact) {
    //Começou o contato
  }
  
  func didEnd(_ contact: SKPhysicsContact) {
    //Acabou o contato
  }
}