Has been also already requested here:Okay, I had this idea in mind for ages now, but now I actually really request it My idea is to give these "Portal" Things a new argument, something like "NoClip" 1 or 0 (on or off). The effect created by this is quite simple: What we ever wanted (and tried to imitate via Duke3D style teleport) can easily be controlled by one simple new argument If the argument is "1", player which enter this fall through the portal floor and get instantly teleported when the eyes wander below the fake floor. It is just like the normal "Deep Water" effect, just that the player gots teleported to the sector "below" the sector he was before.
Okok, my english isn't good enough to explain exactly what I have in mind but I think you guys know what I mean
http://forum.zdoom.org/viewtopic.php?t= ... alse+floor