.. It'll look like THIS, in Quake 4:
http://www.kilnet.org/images/grinderv3bug.jpg
Not sure how hemo and I missed it (or if I somehow putzed it in V2).. but the above shows what happens when you have a vis portal not QUITE touching the adjoining wall (8 units shy, shown here).
The effect is kinda similar to if I had a visible caulk texture, but only appears at certain angles, as shown.
To fix it, I re-released the map for One Last Final version:
http://turkeyfiles.escapedturkey.net/qu ... 1final.pk4
