Real differences between Z-Machine and Glulx?

OK I know I am new to this forum, but how do I choose whether to make my game for a Z-Machine or Glulx?

I would really like to take advantage of web interpreters like Parchment, and I know that’s available for both. But does either format have advantages over the other?

The most important difference is that the Z-machine is limited to 64k of memory, and Glulx is not. I7 can run through that much memory quickly, depending on what features and extensions you use.

Other differences have to do with how sound, graphics, and fonts work. But you’ll run into the memory thing first.

You can choose between Glulx or z-code by clicking on the Settings-tab of the Inform 7 IDE. (This may look a little different depending on whether you are using Linux, Windows or OS X.) I assume you are using Inform 7?

You could just start out writing a z-code game, and switch to Glulx if you run out of memory. How fast this happens mostly depends on the extensions you use.

Or if you include 51 lists in your game. As I learned the hard way, lots of lists will run through the z-code memory limits right quick.

I started out targeting Z-code but eventually blew the limits with a lot of text and extensions. The only drawback I can see is that there aren’t quite as many interpreters for Glulx yet. But the situation is moving in the right direction and there are good interpreters for Mac, Windows, Linux. Also Frotz for iPhone/iPad now supports Glulx and that overcomes a significant limitation previously for Glulx games. I am sure there are some other differences, but for the most part, Glulx just seems like the right way forward.


Is it also a difference that there currently is not a Glulx interpreter available for the kindle? Does anyone know what version of the z-machine the kindle is supporting?

There is no Z-machine that runs natively on the Kindle that I’m aware of. is accessible via the Kindle’s browser.

To my knowledge, Inheritance is the closest thing to a traditional text adventure you can buy on the Kindle Store, and it uses a multiple-choice verb system instead of a full-blown parser.

So Amazon is selling games that run in a browser? I didn’t think the Kindle had a browser. Does anyone here actually develop for the kindle and can talk about how its games are written?

Parchment works on the Kindle 3+. It could have bugs though, so if you find any, please report them at the Parchment bug tracker.

Does this include the branch that runs Glulx games?

The Kindle 3 has a Webkit browser so everything should work as well as in any other Webkit browser.