`Darkness' script

[Loriel]

Someone was once working on a kind of maze or so that was supposed to be covered in darkness, except a small area around the player. That was done with seteffect and showimg'ed lights around the player, which I deemed a bad idea as that could simply be circumvented by switching off light effects.
I made a script that covers everything but a sadly squarish area around the player with showpoly's. I would post it on graal.net, but I think it is ungracefully long. Thus I wondered whether you people could come up with a simpler way to do this requiring less repeteition.