Slashdot Mirror

When I first ran across this it was a few years old. Someone wanted me to port it to Pick Basic as a way to get me interested in programming. It was called Adventure then. Inform has their port source here:
http://inform-fiction.org/examples/index.html

You can write your own (cross platform) Infocom-style (i.e. Z-machine) games with the Inform language.

http://www.inform-fiction.org/I7/Welcome.html

There is an excellent tool for writing IF that a friend brought to my attention a while back. It's called Inform 7.

I have tinkered with it a little bit, and it makes writing IF much easier. It takes out most of the programming skills, and focuses on a pseudo-natrual English way of writing the game.

How about writing Interactive Fiction? Download Inform and he can go through the manual coding alongside it. It's not a traditional programming language, but the concepts are there and easily accessible. Graham's writing really shines in the manual and he explains a lot of complex programming very nicely.

If your kid isn't so much into the writing (or the text only, which is understandable) then I'd start him off with Learn to Program.

Although your kid is probably too old for many of the exercises and activities, but Computer Science Unplugged is a fantastic resource.

I never got into HyperCard, but working with AppleScript, at a time after I'd been using a couple other programming languages, I just found it far too long-winded, and-- as you mentioned-- rigidly so. After the fifth or sixth completely pointless "the" or "of the", I pretty much scrapped it, short of tweaking recorded macros.

Recently, I've been working with Inform 7, a rather recent language for writing text-adventures. Granted, it does have the competitive advantage of being a narrow-purpose language (kind of halfway between "scene description" and programming, really), it struck me from first glance as how a "natural" language like AppleScript should have been ended up. It accepts ambiguity fairly well (albeit with the rare snags resulting from guessing), accepts conjugations, synonyms, general pronouns, and omissions of common grammar, and once you know the general guidelines about "how to talk to it", you can proceed rather naturally.

I played all the mass-produced Interactive Fiction games in the 80s, back when Infocom bought ads in BYTE magazine. Hadn't really thought much about the tools to make such games since then, but obviously, the state of the art has progressed quite a lot. About a week ago, I decided to load up a modern tool called "Inform", which in version 7 takes "literate programming" to a whole new level. From an example in their manual:

Foyer of the Opera House is a room. "You are standing in a spacious hall, splendidly decorated in red and gold, with glittering chandeliers overhead. The entrance from the street is to the north, and there are doorways south and west."

Instead of going north in the Foyer, say "You've only just arrived, and besides, the weather outside seems to be getting worse."

The Cloakroom is west of the Foyer. "The walls of this small room were clearly once lined with hooks, though now only one remains. The exit is a door to the east."

In the Cloakroom is a supporter called the small brass hook. The hook is scenery. Understand "peg" as the hook.

Inform's output is playable in the same Z-machine standards that were derived from Infocom's original machine, that have been released on cellphones, pdas, palmtops, laptops and mainframes for years and years. I'm having fun developing my own short story, and there are a lot of folks remained in the IF world the whole time who have been churning out dozens if not hundreds of titles you can download (most for free) and try. Some are very short, some are quite elaborate.

Try Inform 7. Just to show you how literate programming can be, check out these poems that are compilable Inform 7 games.

That's actually already happened, in a way. After Infocom went out of business the fan community reverse-engineered their VM (the Z-Machine) and Graham Nelson designed a new language and compiler for it (Inform). That, along with other interactive fiction languages/toolkits that compile to their own VMs (TADS, Hugo, AGT, ALAN, and many more) and a small but dedicated community has ensured that interactive fiction hasn't died out.

Every year dozens of new games come out, usually for the two major annual competitions (the IF Comp and the Spring Thing). Most of them are shorter than "commercial-era" games, mainly because they're written by hobbyists who don't have the time and resources to commit to building large games. They run the gamut from puzzle-focused games in the style of Infocom to story-focused games that eschew large numbers of elaborate puzzles to focus on story, and there are also more experimental and artistic games that try to push the medium in new directions. The IF Archive has an extensive collection of these games, and there are several review sites that attempt to catalog and organize the archive. The IF community has long had rec.arts.int-fiction and rec.games.int-fiction at their center, though with the rise of blogs and web forums it has started to fragment some.

In that example, sure. Much of the larger issue is the death of the lone developer. Once upon a time, extremely popular games were written by a single person -- and they were considered good! Those days, needless to say, are no more. (I'm not necessarily complaining -- I adore Half-Life -- but there are also a lot of stories that don't get told, because one person no longer has the resources to tell them alone in the style to which gamers have become accustomed).

As for games which make good use of text-based format, look at the Xyzzy winners in the "Best Use of the Medium" category -- I'm personally extremely fond of the 1998 winner, Andrew Plotkin's Spider and Web. For another example, I doubt very much that Photopia would have as much of its emotional impact were it graphical rather than text-based.

BTW, you might find Inform 7 interesting; it's a toolkit intended to make writing interactive fiction easier for those whose background is more literary than technical (while still leaving plenty of fun for the software geeks among us). Certainly, this kind of toolage makes it far easier for a single individual to put together a compelling game (presuming, of course, that they have the relevant talent) than any graphical framework in which visual artwork, 3D physics, etc etc. needs to be implemented.

The flip-side to "pretty" code is good documentation. There are too few programmers out there who can both write elegant code and explain what it does just as elegantly. I have his "The Inform Designer's Manual, Fourth Edition" sitting on my shelf right now, and I can honestly say that it is the only manual that I have had the pleasure of describing as a "page turner".

The code itself is equally impressive. Satiated with (helpful) comments, compiles on virtually any platform, easy to read, follow, and modify as you see fit. There's also a separate "Technical Manual" for those who are interested in modifying the original code.

Let's see... Let's not forget nethack. They thought of everything. :) http://www.nethack.org/

And then there are always those little tidbits of code like this inverse sqrt function that fall into the it just works category. Code that mere mortals such as myself can hardly comprehend - let alone write! http://www.math.purdue.edu/~clomont/Math/Papers/20 03/InvSqrt.pdf

Bad choice of name. The Z-Machine is a type of virtual machine used mostly for running interactive fiction, interactive tutorials, and the like, and has been for the past few decades. Its specifications are freely available and anyone can implement their own:

• Z-Machine specs from the IF archive
• Z-Machine specs from inform-fiction

Versions have been implemented in C, Java, XUL/JavaScript, and even NewtonScript.

There is actually a fairly large community for games similar to this in the English-speaking world, where it is known as interactive fiction (or by it's old-fashioned name, text adventure). Infocom produced some of the most famous games in this genre, including Zork and the Hitchhiker's Guide to the Galaxy, but there's now a very active community of (mostly) amateurs creating these games just for fun and to explore the artistic possibilities of interactivity in storytelling.

Most interactive fiction these days is purely text based, as that can be easily created by one or two people who have more experience with writing and programming than graphics and multimedia, and doesn't require a large budget or time investment, though you do occasionally see games with graphics. It has become common to write these games to run on a virtual machine, so that they can be run on all kinds of different platforms. The two most common virtual machines are the Z-machine, which has actually been reverse-engineered from Infocom's virtual machine and thus is compatible with most of their old games and tons of old computers, and the TADS VM. Likewise, there are two common authoring environments, which target these machines; Inform targets the Z-machine, and TADS targets, well, the TADS VM. Both have recently released innovative new systems; Inform 7 uses a natural language syntax (similar to the natural language input that controls the game), and TADS 3 is designed to be aggressively object-oriented.

For anyone who is new to these sorts of games, there are a few games that have been designed specifically for beginners. I would recommend Andrew Plotkin's Dreamhold or Emily Short's City of Secrets. You can find lots more games, along with capsule reviews of some of them, at Baf's Guide to the Interactive Fiction Archive. In order to play these games, you'll need an interpreter for the virtual machine. On Windows or Unix/Linux I would recommend Gargoyle, as it's an interpreter that has nice typography and supports many different virtual machines. On the Mac, I would recommend either Zoom (for Z-machine, with support for some other interpreters in beta) or Spatterlight (which supports many different machines).

There is also a large community interested in developing, playing, criticizing, and discussing these games. Some of the best places to go for discussion are the interactive fiction newsgroups, rec.arts.int-fiction (for discussion of interactive fiction programming, game design, and topics about the field as a whole) and rec.games.int-fiction (for announcement and discussion of particular games). There is also an interactive fiction MUD (mostly a fancy chat-room), several contests for developing the best interactive fiction, plenty of reviews and other articles online. There are several good beginner's guides to the format as well.

Anyhow, I thought that since this review made it sounds like interactive novels were mostly a Japanese thing, I thought I'd point out a bit of what is available in the English speaking world. As I mentioned, these are mostly text based, both due to the preferences of the authors and lack of budget, unlike the graphical Jap

It's just an interactive fiction title. There's lots of them, but there hasn't been a successful commercial release in over a decade. There are many free ones available though. Check out the IF Archive to see a pretty large selection of them. There is even free software for making them; check out the Inform language / IF development system for creating new games. Plus, there are annual contests to show off your writing talents. Check out both the IF Comp and the Saugus Ghost Story Contest for a couple of examples.

And of course, there's a whole wiki dedicated to interactive fiction, too.

A good example of what will be easier to write in the next generation of interactive fiction is Galatea, and some of the worked examples that come with inform 7 really showcase its power. I defy you to read through the manual and not come up with an idea for at least one story to implement.

One great article I read that actually made me stop, reread the paragraph, and put down my pilot (I read it in plucker) and think about the implications was in SPAG issue 44. Another couple good articles are in http://brasslantern.org/writers/howto/i7intro.html and http://brasslantern.org/writers/iftheory/i7observa tions.html . Without spoiling the latter article, I'll mention that one of the paragraphs under the 'relations' section blew my mind.

A good example of what will be easier to write in the next generation of interactive fiction is Galatea, and some of the worked examples that come with inform 7 really showcase its power. I defy you to read through the manual and not come up with an idea for at least one story to implement.

One great article I read that actually made me stop, reread the paragraph, and put down my pilot (I read it in plucker) and think about the implications was in SPAG issue 44. Another couple good articles are in http://brasslantern.org/writers/howto/i7intro.html and http://brasslantern.org/writers/iftheory/i7observa tions.html . Without spoiling the latter article, I'll mention that one of the paragraphs under the 'relations' section blew my mind.

It was better than mixing assembly and BASIC. BASIC served as an über-macro assembler meaning that while other people were struggling to write hacky loaders for their machine code, we were coding our own compilers. I wrote an adventure game compiler (which in retrospect I now realise was similar to a baby version of Inform). It would have been a lot harder without BBC Basic.

I confess I didn't bother reading the entire article. There are just too many fatal problems:

Point-and-click programming has failed catastrophically every time it's been tried. My experience (e.g., iShell) taught me that it's too slow and cumbersome for programmers, and still useless for the non-programmers (defined as that vast majority who can't design program logic by any means, graphical or otherwise.) Inform 7 is a recent attempt by IF authors to help others, NOT by making programming unnecessary, but by attempting to impedance match the Author mindset. (I wish them luck, but recognize that most prospective users (the existing IF community) are competent programmers.)

Storytron's basic idea ("thinking, feeling virtual characters" ) is very similar to a system that died several years ago. I can't remember the name, but IIRC it used facial expressions on talking heads as a clue to computed emotional state; "embarrassingly bad" was one of the kinder descriptions I saw. I suspect it hasn't been forgotten by the rest of the IF community either.

Admittedly a lot of IF, with its "guess the magic phrase" problem, can be very frustrating. Their new interaction language, though, has "excruciating user experience" written all over it. If interaction actually requires reverse-diagramming a sentence by point and click (as the article seemed to suggest), I for one wouldn't bother to even try it.

The required commitment (both of time and intellect) for IF works for the small, passionate and closeknit IF community where no money changes hands; since the initial novelty wore off with Infocom, it hasn't ever worked as a commercial product. This is a fundamental disconnect that no imaginable development system or user UI even starts to address. I see zero hope for their business model.

However, at some level, I'm pretty dubious. A tool such as Inform 7 (or TADs, or the other heavy hitters) makes it reasonable to build a narrative that feels spontaneous even if it is not. My gut reaction is that Storytron will have a cursory kind of believability, but when you pressure it a little, it that suspension of disbelief will break down.

By contrast, when I show people what can be done in just a couple of minutes using Inform (and the Inform library, which models the "player world" quite nicely), people immediately think its doing much, much more than it really is, or that I code more than I really do. People want to see storys, which is good for Storyworld, but I think better for Inform.

an attempt to make a text adventure a bit easier to program than basic.

It's off-topic, but check out the latest beta for Inform 7: http://www.inform-fiction.org/ .. IMO, it's probably the greatest thing since sliced bread in interactive fiction, and a really fascinating programming language, to boot. It's heavily rule-based and uses a pseudo-natural language form for readability, and to make it less intimidating to newbies.. It's easier to read it than write it, which is a strange inversion of the norm in programming languages.
  There's plenty of discussion about the langauge itself, and help for neophytes on the rec.arts.int-fiction newsgroup.

  A bit of source-code from the manual, displaying the power of relationships:

        Nearness relates a room (called A) to a room (called B) when the number of moves from B to A is less than 3. The verb to be near implies the nearness relation.
  (this allows you to be able to write rules like:)
Instead of listening when the location is near the Sundial: say "You hear a splashing of water."

Hmm. I may be missing something, but I think you're confusing Choose Your Own Adventure type multiple choice games with the more simulationist, finer-grained parser-based text adventures; the grand-parent post quoted the very first of the latter - the venerable (if primitive) Adventure/Colossal Cave from 1975 (or one of its various, er, mods.)

Popular companies were Infocom, Magnetic Scrolls and Level 9, among others; these days, the form is kept alive by enthusiasts and frequently taken into directions more experimental and/or literary than throw the axe at the dwarf then pick up the gold.

Baf's Guide to the IF-Archive is a good place to start searching; as is the IF Review Conspiracy. Poke around and you'll notice most good games require either a "Z-Code" or "TADS" interpreter (VM); refer to the Inform homepage for a list of UNIX Z-Code interpreters or just go with Zoom right away (link has pretty picture). As for TADS games, here're the Linux TADS 2/3 Playkit and, alternatively, a QT-based TADS 2/3 interpreter.

TADS and Inform, incidentally, are the two most widely used Interactive Fiction programming languages. And although that's not their intended purpose, both have also been used for multiple choice games on occasion.

If you're interested, Brass Lantern has a collection of articles for beginners. If you're not, oh well ;)

Hmm. I may be missing something, but I think you're confusing Choose Your Own Adventure type multiple choice games with the more simulationist, finer-grained parser-based text adventures; the grand-parent post quoted the very first of the latter - the venerable (if primitive) Adventure/Colossal Cave from 1975 (or one of its various, er, mods.)

Popular companies were Infocom, Magnetic Scrolls and Level 9, among others; these days, the form is kept alive by enthusiasts and frequently taken into directions more experimental and/or literary than throw the axe at the dwarf then pick up the gold.

Baf's Guide to the IF-Archive is a good place to start searching; as is the IF Review Conspiracy. Poke around and you'll notice most good games require either a "Z-Code" or "TADS" interpreter (VM); refer to the Inform homepage for a list of UNIX Z-Code interpreters or just go with Zoom right away (link has pretty picture). As for TADS games, here're the Linux TADS 2/3 Playkit and, alternatively, a QT-based TADS 2/3 interpreter.

TADS and Inform, incidentally, are the two most widely used Interactive Fiction programming languages. And although that's not their intended purpose, both have also been used for multiple choice games on occasion.

If you're interested, Brass Lantern has a collection of articles for beginners. If you're not, oh well ;)

There are more text adventures out there than you could probably play in a lifetime!
The really nice thing is, the vast majority of them are developed on either of two system - TADS, the Text Adventure Development System or Inform, Infocom's system. Both are free for anyone to develop their own games with, and there are interpreters for these systems (especially Inform) on just about any platform you care to use.

A good central 'hub' to start from is the IF archive with some beginners guides on how to get started, and a massive collection of games to download and play. and googling for 'interactive fiction' will turn up lots more sites.
Have fun :)

The beta of Inform 7 (A.k.a Natural Language Inform) has already had two extensions written to write Choose-your-own-adventure type games.
  There's the simpler one from Emily Short: http://emshort.home.mindspring.com/CYOA.txt
  And a more powerful, but more complex one from Mark Tillford: http://www.glpics.com/ralphmerridew/Simple%20CYOA

  Inform 7 is a pretty nifty language, and I'm surprised /. hasn't had a story up on the beta yet: http://www.inform-fiction.org/ has the IDE for Windows and Mac OSX. There's an alpha Linux IDE in progress (currently using the Windows compiler through Wine, although a native I7 compiler should be out RSN) over at http://thewhitelion.org/inform7 .. It was down earlier today. Linking to it here probably won't help, huh?
  There's also an overview of Inform 7 language and what it gets you over at http://www.brasslantern.org/

Gamers seem to be caught up with trivial aspects of games. Graphics, console wars & and status seeking has torn apart the community. Did Shakespeare bitch and moan about his lack of fonts? Did Plato refuse to write on shitty papyrus based paper? Did Mozart refuse to write music because he didn't have the right instruments yet--or a mixer for that matter? Did Fritz Lang stop making motion pictures because he didn't have color film and light meters?

To clarify, Inform wasn't Infocom's engine - they used a their own, completely different language to generate their interactive fiction story files. Inform is a language developed separately (and much later) by Graham Nelson, which also outputs story files readable by the Infocom virtual machine, effectively allowing anyone to create their own Infocom interactive fiction.

Inform isn't the only system available for creating IF -- see the rec.arts.int-fiction Authorship FAQ.

On a related note, the Interactive Fiction Competition is apparently still going strong after over a decade, with entries sorted by authoring system.

Inform isn't the only system available for creating IF -- see the rec.arts.int-fiction Authorship FAQ.

On a related note, the Interactive Fiction Competition is apparently still going strong after over a decade, with entries sorted by authoring system.

Damn forgot the link! http://www.inform-fiction.org/

Yeah these are kind of crazy, but...

I always thought Inform would be a cool learning language. It introduces the concepts of objects in a very easy-to-grasp way. It's really easy to throw together a working game.

Also what about something like DarkBASIC? I haven't used it at all, so I have no idea if the syntax is intelligible (or if it teaches good programming practice). Think about how students would respond to something like this, though...

GAMES!

Kinko's has gone way downhill since they got taken over by FedEx. When I needed to print a copy of the nearly 600-page Inform Designer's Manual, Kinkos said it would be an overnight job and cost ten cents a page. So I went to the print shop at Office Depot. They did the job while I waited, at 5.5 cents per page.

Also, if you're sporting the Color Graphics Adapter (CGA) on your PC, descriptive text, dialogue text and user entered text are all color coded for ease of use!

Errrrrm... I'd say bunk. Zork III was a Z-machine version 3 file, and color support didn't come until version 5 (ref: Z-machine specs.

Besides, C64 version of Zork III, to my recollection, only had monochrome text and PC version (just tried on frotz) didn't do any of the text attributes (apart of reverse on status line).

I know, I missed the point. Intentionally. =)

The language Inform is missing from the chart.

Huh. I was about to suggest the major text adventure languages (Inform, TADS, or Hugo), but Flash is a much, much better solution. Easier to learn and (though, as an interactive-fiction fetishist, it pains me to say this) a less esoteric end product.

On the other hand, this is Slashdot - what the hell do you think you're doing posting useful information?

SubEthaEdit sports quite a few different editing modes, including for the Inform language for writing interactive fiction.

Collaborative Interactive Fiction, anyone?

(Quick primer for people unfamiliar with these: TADS is an authoring system and playing system for text adventure games. Z-Code is a platform independent bytecode for text adventure games. Z-Code games were originally produced by Infocom using proprietary tools. Inform is a modern authoring system that also outputs Z-Code.)

TADS has its advantages (a friend of mine who wrote the above mentioned "Magocracy" used it to great effect), but it also has serious disadvantages that must be weighed. Perhaps its most serious disadvantage is that it simply isn't as portable as Z-Code. TADS pretty much has a single interpreter and iffy specs. The only real specs for TADS games is the TADS interpreter itself. Z-Code is well documented at this point with many interpreters being available. TADS interpreters require relatively modern processor and memory while Z-Code was designed to run on home machines from the early 1980s.

All of this boils down to: my old Palm III happily plays very recent Z-Code games but has no hope of running any TADS game. Thanks to Frobnitz I've got 9 games sitting on my Palm right now. Z-Code is so stable that I'm happily running a 4 year old version of Frobnitz

While the interpreter support for graphics is but a pale shadow of TADS, graphics are really the point, are they? Yes, some games greatly benefit from them (I do like the "Earth and Sky" games), they're hardly a requirement for most games. Beyond that the Z-Code spec is quite flexible.

As for the development language, while Inform does have some strange quirks, it's a fine language that reasonably expresses intent. And while I'm a C++ and Perl coder at heart, I'm not so attached to a particular syntax that I'll pick a language based on it.

Ultimately it's telling that TADS games rarely come up in lists of "great interactive fiction you should play." It's dominated by Z-Code games. Apparently Z-Code isn't that limiting.

Don't get me wrong, TADS does have advantages. It shines in graphics integration. The author of Inform has said, "This author at least has long admired the elegance of Mike Roberts's Text Adventure Development System (TADS)," in his own book on Inform and goes on to mention some specific features he likes. Personally I disagree with enough of the library design that I'm tempted to replace it with the Platypus library. But since I'm personally interested in maximizing the number people who can play what I write and I don't have any truly serious problems with Inform or Z-Code, I'll be using that.

(For anyone sold on my little spiel, check out the excellent and free Inform Beginner's Guide and Designer's Manual , the free development software, and an interpreter. Of course, TADS is just as free, so check TADS out yourself.)

(Quick primer for people unfamiliar with these: TADS is an authoring system and playing system for text adventure games. Z-Code is a platform independent bytecode for text adventure games. Z-Code games were originally produced by Infocom using proprietary tools. Inform is a modern authoring system that also outputs Z-Code.)

TADS has its advantages (a friend of mine who wrote the above mentioned "Magocracy" used it to great effect), but it also has serious disadvantages that must be weighed. Perhaps its most serious disadvantage is that it simply isn't as portable as Z-Code. TADS pretty much has a single interpreter and iffy specs. The only real specs for TADS games is the TADS interpreter itself. Z-Code is well documented at this point with many interpreters being available. TADS interpreters require relatively modern processor and memory while Z-Code was designed to run on home machines from the early 1980s.

All of this boils down to: my old Palm III happily plays very recent Z-Code games but has no hope of running any TADS game. Thanks to Frobnitz I've got 9 games sitting on my Palm right now. Z-Code is so stable that I'm happily running a 4 year old version of Frobnitz

While the interpreter support for graphics is but a pale shadow of TADS, graphics are really the point, are they? Yes, some games greatly benefit from them (I do like the "Earth and Sky" games), they're hardly a requirement for most games. Beyond that the Z-Code spec is quite flexible.

As for the development language, while Inform does have some strange quirks, it's a fine language that reasonably expresses intent. And while I'm a C++ and Perl coder at heart, I'm not so attached to a particular syntax that I'll pick a language based on it.

Ultimately it's telling that TADS games rarely come up in lists of "great interactive fiction you should play." It's dominated by Z-Code games. Apparently Z-Code isn't that limiting.

Don't get me wrong, TADS does have advantages. It shines in graphics integration. The author of Inform has said, "This author at least has long admired the elegance of Mike Roberts's Text Adventure Development System (TADS)," in his own book on Inform and goes on to mention some specific features he likes. Personally I disagree with enough of the library design that I'm tempted to replace it with the Platypus library. But since I'm personally interested in maximizing the number people who can play what I write and I don't have any truly serious problems with Inform or Z-Code, I'll be using that.

(For anyone sold on my little spiel, check out the excellent and free Inform Beginner's Guide and Designer's Manual , the free development software, and an interpreter. Of course, TADS is just as free, so check TADS out yourself.)

(Quick primer for people unfamiliar with these: TADS is an authoring system and playing system for text adventure games. Z-Code is a platform independent bytecode for text adventure games. Z-Code games were originally produced by Infocom using proprietary tools. Inform is a modern authoring system that also outputs Z-Code.)

TADS has its advantages (a friend of mine who wrote the above mentioned "Magocracy" used it to great effect), but it also has serious disadvantages that must be weighed. Perhaps its most serious disadvantage is that it simply isn't as portable as Z-Code. TADS pretty much has a single interpreter and iffy specs. The only real specs for TADS games is the TADS interpreter itself. Z-Code is well documented at this point with many interpreters being available. TADS interpreters require relatively modern processor and memory while Z-Code was designed to run on home machines from the early 1980s.

All of this boils down to: my old Palm III happily plays very recent Z-Code games but has no hope of running any TADS game. Thanks to Frobnitz I've got 9 games sitting on my Palm right now. Z-Code is so stable that I'm happily running a 4 year old version of Frobnitz

While the interpreter support for graphics is but a pale shadow of TADS, graphics are really the point, are they? Yes, some games greatly benefit from them (I do like the "Earth and Sky" games), they're hardly a requirement for most games. Beyond that the Z-Code spec is quite flexible.

As for the development language, while Inform does have some strange quirks, it's a fine language that reasonably expresses intent. And while I'm a C++ and Perl coder at heart, I'm not so attached to a particular syntax that I'll pick a language based on it.

Ultimately it's telling that TADS games rarely come up in lists of "great interactive fiction you should play." It's dominated by Z-Code games. Apparently Z-Code isn't that limiting.

Don't get me wrong, TADS does have advantages. It shines in graphics integration. The author of Inform has said, "This author at least has long admired the elegance of Mike Roberts's Text Adventure Development System (TADS)," in his own book on Inform and goes on to mention some specific features he likes. Personally I disagree with enough of the library design that I'm tempted to replace it with the Platypus library. But since I'm personally interested in maximizing the number people who can play what I write and I don't have any truly serious problems with Inform or Z-Code, I'll be using that.

(For anyone sold on my little spiel, check out the excellent and free Inform Beginner's Guide and Designer's Manual , the free development software, and an interpreter. Of course, TADS is just as free, so check TADS out yourself.)

(Quick primer for people unfamiliar with these: TADS is an authoring system and playing system for text adventure games. Z-Code is a platform independent bytecode for text adventure games. Z-Code games were originally produced by Infocom using proprietary tools. Inform is a modern authoring system that also outputs Z-Code.)

TADS has its advantages (a friend of mine who wrote the above mentioned "Magocracy" used it to great effect), but it also has serious disadvantages that must be weighed. Perhaps its most serious disadvantage is that it simply isn't as portable as Z-Code. TADS pretty much has a single interpreter and iffy specs. The only real specs for TADS games is the TADS interpreter itself. Z-Code is well documented at this point with many interpreters being available. TADS interpreters require relatively modern processor and memory while Z-Code was designed to run on home machines from the early 1980s.

All of this boils down to: my old Palm III happily plays very recent Z-Code games but has no hope of running any TADS game. Thanks to Frobnitz I've got 9 games sitting on my Palm right now. Z-Code is so stable that I'm happily running a 4 year old version of Frobnitz

While the interpreter support for graphics is but a pale shadow of TADS, graphics are really the point, are they? Yes, some games greatly benefit from them (I do like the "Earth and Sky" games), they're hardly a requirement for most games. Beyond that the Z-Code spec is quite flexible.

As for the development language, while Inform does have some strange quirks, it's a fine language that reasonably expresses intent. And while I'm a C++ and Perl coder at heart, I'm not so attached to a particular syntax that I'll pick a language based on it.

Ultimately it's telling that TADS games rarely come up in lists of "great interactive fiction you should play." It's dominated by Z-Code games. Apparently Z-Code isn't that limiting.

Don't get me wrong, TADS does have advantages. It shines in graphics integration. The author of Inform has said, "This author at least has long admired the elegance of Mike Roberts's Text Adventure Development System (TADS)," in his own book on Inform and goes on to mention some specific features he likes. Personally I disagree with enough of the library design that I'm tempted to replace it with the Platypus library. But since I'm personally interested in maximizing the number people who can play what I write and I don't have any truly serious problems with Inform or Z-Code, I'll be using that.

(For anyone sold on my little spiel, check out the excellent and free Inform Beginner's Guide and Designer's Manual , the free development software, and an interpreter. Of course, TADS is just as free, so check TADS out yourself.)

I've actually used the IF-optimized language Inform as a teaching aid for computer science. It's a great introduction to object-oriented programming and concepts for beginners.

It's not too hard to learn Inform, at all. The language's manual and tutorial puts most projects' documentation to shame.

Inform homepage

TADS: http://www.tads.org/
Glulx: http://www.eblong.com/zarf/glulx/ (looks like a 32-bit Z-Machine)
Inform: http://www.inform-fiction.org/ (this is the infocom virtual machine)
Hugo: http://www.generalcoffee.com/hugo.html

Everything I need to know about gaming I learned from Pac Man.

Actually, if you get into game making on some of the more primitive platforms out there, like SSI's Unlimited Adventures, or Inform, you'll see that the basic formula of just about all games, and most fiction is what I've distilled down to "Goal + Obstacle." You want something, but something prevents you from getting it.

Whether that something is all the pellets, and the obstacle is some floating ghosts, or that something is to destroy the ring of power and the obstacles are anything Sauron throws in your way, including orcs, Saruman, and The Mines of Moria, and even the weather, the basic idea is the same.

Also, the more you can obfuscate the simplistic nature of the formula, the better. Getting back to Tolkien, he did it by reversing the traditional goal - instead of getting something, you're destroying it. Even your most basic Three's Company plot had these basic elements, and the longer you can keep the goal away from the player/main character, the more satisfying it is once you finally get it.

I think any discussion of plot beyond this, unless it's an expansion of Goal + Obstacle, is overkill, or it shows that the author doesn't really understand what plotting is all about.

The best languages for text adventures are probably Inform and TADS, two languages specifically designed for that purpose.

Their advantages are a good runtime system including the parser, large development communities (well, as large as interactive fiction gets), lots of sample code to help learn, good documentation. The runtime is the key. Each has interpreters on lots and lots of platforms, and they take care of things so you don't have to. Things like undo, parsing commands, formatting, etc.

> Aren't the Infocom games written in their own language for a virtual machine?

They were written for the so-called Z-machine. Many Z-machine games are written in Inform nowadays.

One other little thing (that's sort of an e-book format in a high-tech sort of way) that I'd like to see on every PDA / e-book reader is a Z-Machine (with a Glk virtual machine being an extra bonus) that can be used for er, well, interacting with interactive fiction.

The specifications are easily available (for both Z-Machine and Glk) and so could be pretty readily implemented into any PDA or e-book reader by any competent programmer.

Almost all of the classic Infocom games, except some of the later Zork series, were written in a bytecode-like language which ran on a virtual machine known as a Z machine. This is why the old Infocom games can be played on any platform which has had a Z machine ported to it.

Inform, which is mentioned in the article, is actually a compiler which converts a high-level language into Z-machine bytecode. It was devised and written by Graham Nelson, the author of the breathtakingly-fantastic Curses and Jigsaw . Both of these games, plus the Inform compiler, plus a Z machine for just about every type of machine, can be downloaded from the Inform homepage

"study these rocks, then move towards the crater"

I wonder if they used Inform for the control interface.

Mars
You are on the surface of Mars, millions of kilometers from Earth where you started your journey. The sun is rising in the red sky, only slightly easing the chill of the Martian morning.

There are some rocks here.

> look at rocks

I only understood you as far as you wanting to look at the rocks.

> take rocks

rocks: That's hardly portable.

> examine rocks

You see no rocks here.

> quit

Are you sure you want to quit? y

Z-Code, along with TADS and a couple other formats, is still used by enthusiasts today via the Inform compiler.

Check out some of the five-star games at Baf's Guide to the Interactive Fiction Archive if you're curious! A few of these are at least as good as Infocom's best efforts.

However, I could never come up with the art needed for the graphical adventure.

I think it's a rare person who has the talents of putting together a good story, good puzzles, and good artwork in order to use these tools.

My son has taught himself to program, with only a little guidance from me for learning how to analyze and break a problem into parts, by writing his own text adventure games using a programming language called Inform . This has worked very well - it allows him to express his creativity in the development of a scenario that requires following explicit rules to succeed, and to develop his programming skills in learning to express an algorithm that follows those rules he's created. The Inform community tends to freely share the text adventures they've written - you know a developing programmer is motivated when he spends time pouring over someone else's not-always-well documented source code.