Author:	Drake O'Brien	(a13231@mindlink.bc.ca)

This little litefx.wad should intrigue you.  The effect is quite subtle, 
but interesting.  The effect shows light striking a wall
with no visible source.  All other lighting effects on wall-textures that
I've seen require the wall be contained in the light's source sector - but 
this does away with that requirement so gives a large boost to a level 
designer's artistic freedom.

It isn't likely that it's been done before because it requires the special 
properties of a DMapEdit4.11 or WARM with -na option nodebuild.
I've tried it using BSP and DEEPBSP but it doesn't work.  

The effect works because the sector reference formed by the straight 
fx-linedefs is infinitely thin (vanished).  I hope that makes sense.