1. Introduction

1.1 About Enigma

Enigma is a tribute to and a re-implementation of Oxyd, one of the most original and intriguing computer games of the 1990's. Oxyd first appeared on the Atari ST, but was later ported to many other platforms and extended into a series of four games: Oxyd 1, Per.Oxyd, Oxyd magnum, and Oxyd extra. In 2002 Dongleware, the publisher of Oxyd, finally decided to leave the gaming business and to abandon Oxyd.

Enigma is a clone of Oxyd--with a few unique twists, but altogether very true to the original. Even if you have never played Oxyd, there's a good chance that you will enjoy Enigma, provided you like puzzle games and have a steady hand.

There is an official homepage for Enigma that contains screenshots, downloads, latest news, and the most recent version of this manual. The Enigma developers can always be reached by email at enigma-devel@nongnu.org.

Enigma is free software, i.e., you are encouraged to copy it and give it to your friends (see section 1.4 Distributing Enigma). Enigma is developed by a small group of volunteers, all of us working in our free time. If you like the game please send us an email. It's probably the only thing we will ever get in return for the countless hours we have put into this game.

1.2 Installation

The latest version of Enigma can be downloaded from Enigma's Download Page. This page contains packages for the following operating systems:

Windows

The Windows version of Enigma is distributed as a self-installing executable. Simply download and run the provided `.exe' file.

Unix

Binary packages exist for some popular Linux distributions like SUSE, Redhat, or Debian. For other Unix-like operating systems, building Enigma from source is usually the easiest solution.

Mac OS X

No installation is necessary for the OS X version, simply execute the `.dmg' or `.tar.gz' file.

The download page usually contains more detailed and up-to-date information. If you cannot get Enigma to work on your computer, feel free to ask for help on the Enigma mailing list (enigma-devel@nongnu.org).

1.3 Emulating Oxyd

As mentioned in the introduction, Enigma started out as a clone of Oyxd. By now, Enigma is finally capable of emulating most of Oxyd's core functionality, although the gaming experience isn't perfect yet. Enigma still lacks some of Oxyd's game objects, and features like network support are completely missing. What does work, however, is importing Oxyd's sound effects and playing many of the original levels.

Enigma will automatically import every Oxyd data file it can find. By default it searches for data files in the following places:

Windows

There's a `data' folder in Enigma's installation directory, the location of which you can specify in the installation program. This is usually something like `C:\Program Files\Enigma\data'.

Unix / OS X

There are two possible data directories on Unix-like systems: firstly the system-wide directory (something like `/usr/local/share/enigma' or `/usr/share/games/enigma', depending on your configuration), and secondly a per-user directory called `.enigma' in your home directory.

All you have to do is copy one/any/all of the following files to Enigma's data directory (remember that case does matter on Unix-like operating systems):

Per.Oxyd and Oxyd 1 are "dongleware" (i.e., some kind of shareware) and can be downloaded freely from the Internet (search for "oxyd abandonware"; Google is your friend). Oxyd extra and Oxyd magnum were regular commercial games, so you may use the data files only if you have a legal copy of these games. Please do not ask us to send you copies of any Oxyd version--we won't. Oxyd may have been abandoned, but it's still copyrighted, and we respect that.

1.4 Distributing Enigma

Enigma is free software and may be distributed under the terms of the GNU General Public License (GPL). This license comes with every Enigma release (either in file `COPYING' or in file `COPYING.txt'). If all you want to do is play Enigma, you don't really need to read all that legalese (you probably wouldn't anyway). For you, the license basically says: Play Enigma as much as you want, as long as you want, and be sure to give it to all your friends!

If you want to modify Enigma or contribute to its further development, please do read the license, if only this one time in your life. The GPL insures that Enigma will remain free software in the future. In particular, if you modify Enigma or distribute modified version, you may not deny anyone else the right to use, modify, and distribute Enigma or its derivatives.

The preceding two paragraphs are no substitute for the real license, but a summary of its main traits in plain English. Please consult the GPL or ask if you are unsure or if you need to know more details.