There are several tunnel effects in the XScreensaver collection and rss-glx (timetunnel, atunnel, blocktube, hufo's tunnel). I don't know if any of them use thi

There are several tunnel effects in the XScreensaver collection and rss-glx (timetunnel, atunnel, blocktube, hufo's tunnel). I don't know if any of them use this same approach. Maybe Hufo's tunnel does, it looks similar.