tads.org > HTML TADS vs. Plain TADS

HTML TADS vs. Plain TADS

TADS interpreters come in two varieties: text-only and multimedia, also known as "plain" and "HTML." A lot of people have found the distinction confusing, but that's really only because no one's properly explained it to them - the differences are actually pretty straightforward once someone explains them.

This article will try to explain the differences, and hopefully will clear up any confusion about the two kinds of interpreters.

The difference in a nutshell

The difference between HTML TADS and plain TADS boils down to one thing: the display capabilities.

Everything else about the interpreters is the same. In particular, the core "virtual machine" engine - the part that reads and executes the game program - is identical in the two types of interpreters.

If you're old enough to remember the days of yore, when computers were refrigerator-sized monstrosities sealed away in glass rooms and people ran programs from terminals, you can think of it this way: HTML TADS and text-only TADS are different kinds of terminals, and both attach to the same "TADS mainframe." That central computer is the virtual machine core, and it sends out display instructions to the terminals. If the player is running the text-only type of terminal, then that player will only be able to see regular text; the terminal is too simple to understand things like graphics or fancy text formatting, so it simply discards any of those instructions that come across the wire. If the player is running the multimedia kind of terminal, though, the terminal understands all of the advanced instructions, so it will display everything the TADS mainframe sends it.

If you grew up in the modern world with PCs and internet browsers, here's an analogy that might make more sense: text-only TADS is like a Netscape pre-beta version from 1996, and multimedia TADS is like the latest and greatest version of your favorite browser. You can look at any web site with either one, but if you have the old version, it won't be able to show you the full features of a lot of current sites - it'll show what it can, but it will ignore a lot of the formatting instructions from modern sites because those features simply didn't exist when it was written. If you want the full experience, you need to use the modern browser.

Frequently asked questions

A number of questions come up repeatedly about the differences between the two types of interpreters. We'll try to answer them here.

Exactly which interpreters are which?

The multimedia interpreters include:

The text-only interpreters include:

For details on how to find and download any of these, see the TADS 2 page or TADS 3 page, depending on which generation of TADS you're interested in.

Do I need to install both kinds of interpreter to play different games?

No. If there's a multimedia interpreter for your platform, you can simply install that, and you'll be able to play any TADS game. The multimedia interpreters are "universal" - they can play all TADS games, whether they use the advanced multimedia features or not.

If your platform doesn't yet have a multimedia TADS interpreter, you can still play most TADS games with a text-only interpreter. If you run a game that uses multimedia features, the text-only interpreter will simply ignore the features that it can't handle. For example, if the game tries to display a picture, a text-only interpreter will ignore the picture, but will still show the ordinary text the game displays. Many authors working with HTML TADS design their games so that the game is still playable without the multimedia features - for example, by ensuring that any vital clues in a picture are also present in plain text.

How do I know which interpreter to use for a given game?

See the previous question - just install the main interpreter for your platform (multimedia if one is available, otherwise the text-only version), and you'll be set.

There isn't a multimedia interpreter for my operating system. Can I still play HTML TADS games?

Yes, for the most part - as explained above, a text-only interpreter will happily run a game that was designed for HTML TADS, and will simply ignore any multimedia features the game uses. Most multimedia games are still playable in text-only mode, although you'll of course miss the visual and audio extras the author provided. A few games might be so dependent on the visual or audio aspects that they won't be playable in text-only mode, but in practice that seems to be rare - most authors take into account that some players won't have multimedia interpreters, and design their games to adapt gracfully to a text-only environment.

Isn't a GUI interpreter the same as a multimedia interpreter?

No. This is one of the more confusing aspects of the HTML-vs-text situation, since it seems like an interpreter designed for a graphical system like Windows or Macintosh ought to automatically be able to show graphics. But that's not the case - even on a graphical operating system, applications have to be specially programmed to handle graphics and sound effects and so on. Only the multimedia interpreters have this special programming. The other interpreters for GUI systems - such as WinTADS, MacTADS, FrobTADS, QTads - don't have this special programming. So, even though they run on GUI operating systems, they still can't show game graphics or play sounds or use the other multimedia TADS features.

What's the difference between WinTADS and HTML TADS?

WinTADS is a text-only interpreter, and HTML TADS is a multimedia interpreter. Both run as native Windows applications, but WinTADS can't show graphics or use other multimedia TADS features.

(Note that WinTADS is essentially obsolete at this point. Stephen Granade wrote WinTADS in the days before HTML TADS came along, because there was at that time no native Windows version of TADS - you could run the MS-DOS version in a Windows DOS-box, of course, but that's kind of ugly compared to a native Windows application. When HTML TADS appeared, Stephen decided to stop maintaining WinTADS, since HTML TADS is essentially a superset of WinTADS - HTML TADS is also a native Windows program, and can run traditional text-only games in addition to multimedia games. Since Stephen hasn't updated WinTADS in a while, it's based on an older TADS VM engine and thus can't run some of the latest games.)

What's the difference between MacTADS and HyperTADS?

MacTADS is a text-only interpreter, and HyperTADS is a multimedia interpreter. Both run as native Macintosh applications, but MacTADS can't show graphics or use other multimedia TADS features.

Which compiler do I use to write HTML TADS games?

There's only one TADS compiler - you use the same version to write text-only and multimedia games. There's absolutely no difference in the tool set; it's just a matter of writing the extra multimedia formatting instructions in your game's source code.

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