box1
box2
Only the second box should have a repaint.

(GraphicsLayer
  (anchor 0.00 0.00)
  (bounds 785.00 658.00)
  (children 1
    (GraphicsLayer
      (bounds 785.00 658.00)
      (contentsOpaque 1)
      (children 2
        (GraphicsLayer
          (position 8.00 8.00)
          (bounds 300.00 300.00)
          (drawsContent 1)
          (mask layer)
            (GraphicsLayer
              (bounds 300.00 300.00)
            )
        )
        (GraphicsLayer
          (position 8.00 308.00)
          (bounds 300.00 300.00)
          (drawsContent 1)
          (mask layer)
            (GraphicsLayer
              (bounds 300.00 300.00)
              (drawsContent 1)
              (repaint rects
                (rect 0.00 0.00 300.00 300.00)
                (rect 0.00 0.00 300.00 300.00)
                (rect 0.00 0.00 300.00 300.00)
              )
            )
          (repaint rects
            (rect 0.00 0.00 300.00 300.00)
            (rect 0.00 0.00 300.00 300.00)
            (rect 0.00 0.00 300.00 300.00)
          )
        )
      )
    )
  )
)