They have a page where they released a lot of gdc and tech talk slides/papers. Google it. 

http://www.valvesoftware.com/publications/2009/ai_systems_of_l4d_mike_booth.pdf

This slideshow presentation, although I can't find the talk associated with it, is basically where most of the actual talking about the director has been done, as well as bits and peices on the valve developer wiki in regards to working on L4D maps.

In short, it's a mix of random chance, algorithims for how 'tense' the gameplay has been, and some level design scripting. 

been looking into doing this for quake. looking into l4d mapping tutorials, i don't think i'd make it quite that automated, but it'd be pretty cool to have a sort of sub-layer of gameplay that's randomly generated. 

Lardarse's randomizer can randomize monster spawns from pre-set groups, or spawn monsters in random places... unless this is totally not what you want. 

not at all.

simply randomizing a group of monsters isn't what i'm thinking of.

essentially, what i'd like to work towards, is a system that can populate a single player map (or even a dm one, i suppose?) with monsters on it's own such that it seems like a proper map.

like a more advanced dmsp in some ways, i guess. 

Can an auto-spawner ever be as good as a level designer hand-placing enemies? Wouldn't the mapper have to define possible locations, at least?

Might depend on the map? DMSP works because a DM map is nonlinear and arena-ish by design. 

yeah, the system i have works fine for a dm type map. now the goal is to have the ai place monsters ahead of the player which is a little more challenging. 

DO YOU NEED TESSSTTTEEEEERRRRRSSSSS??????

/me raises hand 

too early atm, but i'll put you on the list. :)

i think the goofy thing about it is that, in left 4 dead, it makes sense that there are zombies sort of randomly everywhere-- haphazardly placed by the ai.

but in quake, it's kind of weird seeing soldiers and such just randomly pop up in areas. 

So, to the player, a monster spawned is a random monster... at least, the first time the map is played. 

I felt like playing my vertical map again. On Normal. Boy, what annoying gameplay... Sorry to all of you who had to suffer through it unprepared. 

it's kind of interesting to replay your own maps after a year or more. long enough to forget them anyway. 

something similar to DMSP mod? Can't remember who coded that though, maybe a place to start though? 

I felt like playing my vertical map again. On Normal. Boy, what annoying gameplay... Sorry to all of you who had to suffer through it unprepared.

It's about time for an excuse. Damn, that was annoying.

;-) 

Apology.

Being German breaks another joke. 

but maybe I just have bad taste. 

always nice to replay maps, I usually replay paks because I always forget many things :) Arcanum will take me next month :) will run all the roads again untill I defeat then at Hard in one shoot! 

LOLOL.

Mappers AND testers would do well to remember that their entire audience will be playing through the map for the first time, not the n-th time ;) 

Not sure where to post this, but it seems as though the zip for The Tale of Abbots Rune by Spacegod is fucked. 

http://www.quaddicted.com/reviews/sgodrune.html ?
zip file is fine, problem at your end.