Hi,
setting up a feedback-effect is easy. There should be a [FeedbackExample] operator that illustrates the rough idea: The [RenderToImage] operator makes it's buffer available through an ID. Further down, you can reuse this buffer via the [ReuseImageBuffer] operator.
[TrueColors] is a nice example of how complex these effects can become.
However, getting such effects under control can become tedious.