title: Track the position of SKSpriteNode while doing a SKAction moveTo
body: <p>I'm trying to figure a way to track a postions for multiple nodes, that spwan randomly on the screen so i can make a changes to them while moving when the reach random postion.</p>
  
  <p>the nodes just move along the x axis and i want to be able to generate random number from 0 to postion.x of the ball, and change the color when it reachs the postion </p>
  
  <pre><code>override func update(currentTime: CFTimeInterval)
  </code></pre>
  
  <p>i tried tacking changes in update method but as soon as new node appers i lost track of the previos one</p>
  
  <p>i also tried</p>
  
  <pre><code>        let changecolor = SKAction.runBlock{
          let wait = SKAction.waitForDuration(2, withRange: 6)
          let changecoloratpoint = SKAction.runBlock { self.changecolorfunc(self.ball)}
          let sequence1 = SKAction.sequence([wait, changecoloratpoint])
          self.runAction(SKAction.repeatAction(sequence1, count: 3))
      }
  </code></pre>
  
  <p>but it doesn't give me any control over the random postion</p>