DVDScene3.swift

// Update is called once per frame
public override func update(_ currentTime: TimeInterval) {
  // Collect a reference frame for the node's current position
  let currentFrame = dvdNode.calculateAccumulatedFrame()

  // Top bound
  if currentFrame.maxY >= self.frame.maxY {
    moveTransform.ty = -1.0
    dvdNode.run(changeColor)
  }

  // Right bound
  if currentFrame.maxX >= self.frame.maxX {
    moveTransform.tx = -1.0
    dvdNode.run(changeColor)
  }

  // Bottom bound
  if currentFrame.minY <= self.frame.minY {
    moveTransform.ty = 1.0
    dvdNode.run(changeColor)
  }

  // Left bound
  if currentFrame.minX <= self.frame.minX {
    moveTransform.tx = 1.0
    dvdNode.run(changeColor)
  }

  // Update the node's position by applying the transform
  dvdNode.position = dvdNode.position.applying(moveTransform)
}