Interview with László “Avenger” Tóth on the 20 year anniversary of GemRB

László “Avenger” Tóth, a long time project maintainer, was one of the most prolific contributors to GemRB, tools for modding and the wider quest to understand the original engines. On the occasion of the anniversary, we asked him a few questions.

1. How did you find your way into GemRB?

I was still modding and coding my editor in the TeamBG community when Balrog approached us with his budding project. It could already render bg1 areas and had all the basic framework in place. This seemed ideal to me, because I couldn’t myself start such a big project, do the administration and all the other jobs, but there was still a lot to do.

2. Was it hard to get other people interested to contribute? How helpful were platforms like SourceForge, FLOSS communities of the time and the game fanbase?

There were always interested people, but it was somewhat hard to keep them. I think we were understaffed by 1-2 people, and this slowed the work a bit. Especially when Balrog left us, but luckily we had enough people at that crucial time. SourceForge was a bit different at that time. The fanbase was always mixed, we had many trolls who couldn’t believe that GemRB would ever work and “supported” us with trolling. There were also fans who tried to compile GemRB (and succeed) on the wildest platforms I could imagine.

3. For you, was reverse engineering more a thing of testing the games or looking at the disassembly? What tools and tactics did you use, especially considering there are 8 major versions of the IE engine out there?

First, reverse engineering (with IDA) was a necessity. We couldn’t continue work on a few obscure parts that seemed to be used internally, but there was no way to directly test them. It took me a week to get a grasp of the effect framework. By that time, we already had something in place, and I was surprised that a lot of things were coded exactly the same way we did. By the end of my work, I had 99% of the code recovered and I could read it like it was source. Having decoded one engine, the rest was much easier (The first disassembly worked like a Rosetta Stone).

4. Was there any help or obstruction from official developers at any point?

No, there was never any obstruction from developers (Neither Bioware nor Beamdog). A minor obstruction was that I got hired by Beamdog, so that kinda ended my GemRB involvement. Not like they forbid it, I just couldn’t work on the “same” code all the time.

5. Do you remember some contributions that you’re really proud of? Or a problem that was especially infuriating to solve?

I’m pretty proud of the effect subsystem. The fact that the same GemRB version could simulate all the Infinity versions. To some degree, I also like the projectile system, some parts of it (mostly the extended .PRO structures) got their way into the EE engine.

6. Do you remember any amusing anecdotes, discoveries or original engine quirks? What’s the worst hack or most silly design that you encountered?

There were ugly hacks, and hacks of hacks, but I don’t always remember the time when I discovered them (at the time I already saw the original Infinity code, or not). So best lets not talk about what is under the hood. One can look at GemRB and find their ugly hacks there, rest assured, it isn’t looking worse than the original.

7. Which one was your favourite IE game and do you still play it? Or other old games? Or contribute to other reverse-engineering/reimplementation projects?

My favorite game as a player was Planescape Torment, but as a reverse engineer / coder I hated it and even seeing the original code didn’t help that feeling. After I finished my involvement with Beamdog, I don’t think I will ever play any other IE game. Unless someone makes a totally new one with GemRB.

8. Any final thoughts about IE games and GemRB 20 years later?

I hope someone finds GemRB useful and motivating enough to develop a new game.

Tune in tomorrow to hear from lynx, the current maintainer that succeeded Avenger.