multigen

source for everything in this post because there's no other information i've found

you can get multigen.c and multigen.txt from here

multigen:
Generates the state tables used in the Doom source code (info.c).
The script file used to build Doom's state tables is included
(multigen.txt).

multigen.txt looks like this: https://dl.dropboxusercontent.com/u/8943931/multigen.txt


Multigen looks like the in-house equivalent of iD's dehacked/decorate editor. It's sensible that they weren't literally hard-coding all state definitions directly to c, but it turns out this tool outputs the data to c code anyway.

The outputted data: info.h info.c

Has anyone looked at this/worked with it at all before? My proposal is to repurpose multigen.c to build the data that info.c stores, but at runtime rather than before compilation. If multigen could be a standard lump in a doom wad, it would be a completely true-to-vanilla yet more powerful and standard editing format for State definitions.

This tool was released in 1998 and no one has ever really given it a second thought to the best of my knowledge. No one ever bothered even uploading it to /idgames until 2011: Doom utilities

In 1998 it would have been a nice way for Boom to generically extend the state table (which is one of the biggest missteps that the Boom team made IMO - keeping everything locked into the 1000ish states in the state table with no way to extend it), and we would probably appreciate it now. Not sure how useful it is now, since people who want to add a bunch of new stuff almost invariably use ZDoom / DECORATE, and trying to retrofit it into Boom compatible source ports would be a lot of effort for little apparent gain.

I think even if it doesn't become some kind of standard way of managing the state table (which is definitely a big ask at this point), I think it'd be worth exploring to some extent anyway. Maybe just a proof-of-concept port/addition to chocolate doom

Udo Munk's XDoom port (c. 1999-2000, maybe early versions before that) used it to add translucency and smoke effect to some sprites. It was a very nice port back then (before PrBoom) but I don't know the technical details. I can tell you that it doesn't build on modern system anymore (tried it several years ago...) Would need some TLC to get it going again, but probably nobody will care anymore.

Anyway you can find the code in /idgames/source, along with xwadtools (which you'll probably need if you ever want to build it). In the tarball, ./xdoomsrc/data has his custom multigen input file. He seems to have modified the tool itself also (the one in xwadtools).