Anyone have any information about ADL?

[Jalen]

I hope this isn't off topic for this forum; it's not about AGI or SCI, exactly, but it's about their direct predecessor, so it's not entirely unrelated, and I'm hoping that there are enough Sierra fans here that someone might know something...

As the topic title says, I was wondering if anyone had any information on the details of ADL, the "Adventure Development Language" created by Ken Williams and used for the Sierra "Hi-Res Adventures".  Specifically, I was wondering if the details of the syntax and structure of the language were available anywhere—enough for someone to create a new game that used the same engine.  ScummVM can run ADL games, so clearly someone has figured out the format, but despite fairly extensive searches online I've been unable to find anything useful.  (It doesn't help that "Adventure Development Language" is a generic enough name to make it hard to search for specific information on it.)

I do have a reason for asking about this; I'm starting a blog about game creation systems (well, not right away, but it should be launching some time in the next year—I'm trying to get some prep work done first).  My intent is to go chronologically covering the various game creation systems and engines that have existed over the years, and trying if possible to make a game with each one.  (I'm not sure how far I'll ultimately get, but at least up through the 80s there are few enough such systems that a comprehensive approach may be doable.)  ADL is one of the earliest game-creation systems/engines I've found (not the earliest, but within the first twenty or thirty), but of those early engines it's one of those I'm having the most trouble finding detailed information about, second only to a really obscure system from 1979 called F.  So if anyone could point me to where I might be able to find out more about ADL's format, I'd really appreciate it.

(Of course, I'll be covering AGI and SCI in my blog eventually too, but they came later so they're further down the line... and anyway, there seems to be plenty of information about them available online, not least at this site, so I don't have any questions about them.  At least not yet... maybe when I get to them on my blog I will.)

I'm particularly hoping to cover ADL on my blog because, well, I actually have my own fond memories of those old Sierra games... I'm old enough to have played the "Hi-Res Adventures" as a child; I don't think I ever solved The Wizard and the Princess, but I think I did solve Mystery House and Mission Asteroid, and (most of?) The Dark Crystal.

Anyway, again, if this is off-topic for this forum I apologize, but I'm hoping since it's about a Sierra adventure system it's at least close enough to this forum's bailiwick.  If anyone has any information on ADL, or can point me to where I can find it, I'd definitely much appreciate it.

(And, as I said, I may have questions about AGI and SCI when I get to them in my blog, but that may be a while... though maybe not all <em>that</em> long; AGI is within the first fifty or so systems in my chronological list.)

[ZvikaZ]

Hi.
I think it's a good question, and your planned series sounds like a great idea. Please update how it's going!

Regarding ADL - you might want to read Ken Williams' recent book. He speaks a little about how they designed the mystery house, gives examples of Roberta's tables that described the games, and few more details. He doesn't give exact technical details, but still, it might interest you.

Regarding ScummVM's ADL support - you might want to speak with ScummVM guys. I assume they will be glad to give you more information. You can even interview waltervn who developed the ADL engine for ScummVM. I think that the reversing effort is an interesting story; and anyway, he's probably one of the people who know most about ADL today...

He's reachable in ScummVM's Discord server, under that nickname.

[OmerMor]

I second Zvika's suggestions.
Additionally, you might try to reach out to Ken himself. He's on facebook.

[Collector]

I would be very interested about anything that can be found ablut it, too. Another thought about SVM is that it is open source and you could take a look at the source for their ADL engine handling.

[Jalen]

Thanks for all the suggestions.  (And sorry for not replying sooner; had a busy couple of days.)

Additionally, you might try to reach out to Ken himself. He's on facebook.

While I didn't try to contact Ken Williams on Facebook, I did post my question on the forum on sierragamers.com and got a reply from Ken Williams there.  While he was very genial in his reply, he didn't have much information to share:

I don’t know if it was ever reversed engineered or documented. I wrote it, and put what little I remember about what it was like into my book (www.kensbook.com).

I wish you luck, but I’m not sure there is much information out there..

However, I did learn one thing from his replies that I found interesting.  The above quote doesn't come from his first reply; here's his previous post in the thread:

You’ve stumped me. I have no idea what ADL is. Are you sure Sierra ever had something called ADL?

It was after I clarified that I was referring to the engine used in the Hi-Res Adventure games that he posted the other reply, along with the following information:

I don’t remember ever giving that system a name. Thus, ADL seems a good fit.

So it seems, contra what's stated in several places online (and in the book Hackers: Heroes of the Computer Revolution, which is probably where at least some of those sites got the information), that "Adventure Development Language" is not what Ken Williams called the Hi-Res Adventure engine.  Maybe that was a name used by other people at Sierra, but Ken Williams himself didn't recognize it.

Regarding ADL - you might want to read Ken Williams' recent book.

Heh... as stated above, Ken Williams himself made that same suggestion.  Yeah, I'll definitely be picking up a copy of his book.  Honestly, even if I weren't trying to do research for my blog, it seems it would be an interesting read.

Regarding ScummVM's ADL support - you might want to speak with ScummVM guys. I assume they will be glad to give you more information. You can even interview waltervn who developed the ADL engine for ScummVM. I think that the reversing effort is an interesting story; and anyway, he's probably one of the people who know most about ADL today...

He's reachable in ScummVM's Discord server, under that nickname.

Ah.  I had seem on the ScummVM wiki that waltervn was the person who developed the ADL engine for ScummVM; I found his github page and took a look; but I hadn't tried reaching out to him.  That definitely may be worth a try, especially if he's reachable in ScummVM's Discord.  (Though I admit I'm kind of a newb when it comes to Discord; I've used it a bit, but I don't really have much experience with it.)

Another thought about SVM is that it is open source and you could take a look at the source for their ADL engine handling.

Oh, yes, that occurred to me, and it's definitely something I can do if nothing else pans out, but... it's kind of a last resort.  Trying to look at the code from the ScummVM ADL engine and reverse engineer the engine from there is... doable, but seems like it would be time-consuming.  I'm not averse to delving into code; I'm already in the process of going through the original C code of one old engine and porting it to Javascript to make it runnable online; but the more time that goes into that sort of thing the less time I'll have to, well, actually use the engines and make games.  Still, yes, if I don't manage to find the information any other way, I'll look into the ScummVM ADL source code.  (But I think first I'll see if I can get any help from waltervn as ZvikaZ suggested.)

Thanks again for the replies!  I was a bit worried this question might be a little off topic for these forums, but I appreciate all the suggestions you've offered.

[ZvikaZ]

Nice update.

You might be interested in searching this forum for various threads regarding historical issues. I vaguely remember (*) few occasions that the conclusion was that the human's memory is weak, and if you have some hard evidence regarding something, that contradicts some ex-employee's memory, many times the ex-employee just doesn't remember well...

And of course, Ken Williams himself might be wrong (I'm not saying that he's wrong, I'm just raising the option that he doesn't remember well, and you should verify what he says...). And besides, when you'll read his book, you'll see that his general attitude is (in my words... ) "I'm looking forward to the future, and don't think about the past too much", so he gives the impression that he didn't try hard to memorize those things.

Anyway, if you'll ask *me* about things that I've done more than 30 years ago, I will probably forget most of the details...

(*) It's an interesting irony, that I've just demonstrated my claim by 'vaguely remembering' what I've read here

BTW,
You might want to read this thread: http://sciprogramming.com/community/index.php?topic=1668.0
And it refers to a post in a *very* comprehensive blog series: https://www.filfre.net/sitemap/ , which I think you should also check.

[Jalen]

Oh, yes, I'm definitely familiar with The Digital Antiquarian; several of the systems on my list I found out about from there.  However, one of his main sources of information about the early days of Sierra is the aforementioned book, Hackers: Heroes of the Computer Revolution, by Stephen Levy, so the mention of the name ADL seems to come down mostly or entirely to that one source, and I'm... not convinced that source is reliable, and certainly wouldn't consider it "hard evidence".  Yes, it occurred to me that Ken Williams could have misremembered, but while I agree that people don't retain vivid memories of events from forty years ago, his not recognizing the name of a system that he himself created (even forty years later) seems... maybe a bit much.

According to the author's notes in Hackers, the author's primary source was "over a hundred personal interviews" (he doesn't specify the interviewees).  So basically it seems to me there are three main possibilities here:

• Stephen Levy misunderstood something from one of the interviews he conducted
• Some ex-Sierra employee Levy interviewed told Levy that Ken Williams called his system ADL, but was lying or mistaken
• Ken Williams so completely forgot the name of the system that he invented and that launched his company that he didn't even recognize it on seeing it years later

While the last alternative isn't impossible, it strikes me as the least likely of the three.

In any case, at this remove, short of some contemporary document turning up signed by Ken Williams and mentioning ADL by name (or conspicuously leaving the system unnamed), I don't think there's really any way to "verify what he says"... I guess it's basically his word against Levy's, and Williams seems to me to be the more credible source.  But yeah, you're right; when I do cover ADL on my blog and discuss this, I should acknowledge the possibility that Williams is misremembering and he did name his system ADL—I don't personally think it's likely, but it is a possibility.

There is some interesting information in that thread; thanks.  And yeah, I will search this forum to see if there's any other relevant information about historical issues.

[ZvikaZ]

You've convinced me.
Now I'm really looking forward to read your series