# Freedoom

Freedoom is a project to create a complete Doom II-compatible IWAD file which is Free Software.

The IWAD file is the file used by Doom which contains all the game data (graphics, sound effects, music, etc.). While the Doom source code is Free, you currently still need one of the proprietary IWAD files from id in order to play Doom. Freedoom aims to create a Free alternative. Combined with the GPL-licensed Doom source code this will result in a complete Free Doom-based game.

For more information, see http://freedoom.nongnu.org/.

## What “Free Software” means

When we speak of Free Software, we refer to the software movement in which your freedoms to use, copy, modify, and study it are ensured. For example, you may freely use Freedoom for any purpose you see fit, you may redistribute it to anyone without needing to ask for permission, you may modify it (provided you keep the license intact, see `COPYING`), and you may study it — for example, to see how a Doom IWAD is built. To facilitate this, you can get the full source code (here, in the form of a DeuTex tree) for Freedoom.

You may read more about Free Software at the GNU and Free Software Foundation websites.

## Contributing to Freedoom

Contributions to Freedoom are always welcome, however there are a few guidelines that should be followed:

### Intellectual Property

We know people hate legalese, but this is important. This applies to everything which is submitted.

You must be incredibly careful when basing on existing graphics or sounds. Most Doom projects are incredibly lax on reusing intellectual property — there are plenty of WADs out there which contain modified Doom sprites, for example. However, due to the nature of this project, we do not have the same liberty to rip as we please.

The general rules go as follows:

- Everything you submit must be 100% your own work. You must not base upon resources from Doom or any other game. You may not even rip textures from WADs you have downloaded (if you find a WAD with textures in which look useful, let us know — that way, we can contact the author).

- Do not simply copy the original resources. Where possible, try to make an effort to make the new versions look visibly different from the originals.

- Be especially careful of “free texture” (or “free sound” or “free graphic”) sites. Although these would appear at first to be okay to use, many are free for “non-commercial use only”. One of the things we want to be able to do is put this on GNU/Linux CDs (which are sold — “a commercial use”).

- The main exception is that you may of course reuse anything in the Freedoom source tree. In fact, this is encouraged, as reusing material will give the WAD a more consistent feel.

### Levels

Levels should be in Boom format; you may exceed the limits of Vanilla Doom and use Boom features; however, do not use features that are not supported by Boom 2.02 and compatible ports. Levels should be in Doom’s original format, not in “Hexen” format.

It is sensible to also heed the following guidelines:

- Make sure that skill levels are implemented, and that all multiplayer start points are present.

- Make levels appropriately difficult for their position within the progression of the game. Also bear in mind that not all players may be as skilled a player as you.

- Do not use tricks that exploit Doom’s software renderer; some source ports, especially those that use hardware accelerated rendering, may not render it properly. Examples of tricks to avoid include those used to simulate 3D bridges and “deep water” effects.

- Boom removes almost all of the limits on rendering; however, do not make excessively complicated scenes. It is desirable that Freedoom levels should be playable on old or low-powered hardware.

- Always test in Boom itself rather than a derivative such as PrBoom. This ensures that your levels really are Boom-compatible rather than using any extra features. As DOS is rather rare these days, you may not have a system which can run Boom natively, so you may use either DOSBox or FreeDOS.

### Graphics

- Graphics should be the same color and size as the originals to remain compatible with PWADs (otherwise, they may end up looking like a mess). They cannot use the Doom font.

- Textures should be the same dimensions as the originals. They should be similar but not identical (to avoid IP infringement) —  in fact, they shuold be as different as possible while keeping to the general theme of the texture. As mentioned above, try to make a concious effort to make the textures visibly different from the originals. Critically, the textures should tile in the same way as the originals.

- Some textures contain the letters UAC or references to UAC; this is an intellectual property of id Software (trademarked). Instead, use the letters AGM in your textures.

- Sprites should be roughly the same size and shape, but different to the originals. Doom monsters are id’s intellectual property (which means no imps, cyberdemons, etc). The new monsters will behave the same way as the originals, but will be totally new.

### Build process

The Freedoom build process is fairly complete and should not change without good reason. Write a decent explanation why your method is better; just enough to get your point across is good enough.

### Documentation

Freedoom always needs help with the documentation, so please send your patches, but keep in mind:

- We use AsciiDoc for writing the documentation. AsciiDoc is a simple plaintext-based format which is simple to read and write in its source form, and makes pretty HTML documents out of them (it also supports other formats like DocBook/PDF/manual pages…).

- Headers are formated in a wiki-style format, this makes it easier for Vim (perhaps other editors, too) to automatically re-format text.

- Text is kept at 72 characters wide. In Vim, you can set the editor to automatically insert line breaks as you’re typing by performing `set textwidth=72`. Special exceptions to the width rule might be allowed when necessary (for example, inserting long URLs).

### Submitting your work

TODO: Figure out the best method of doing this. This mainly requires time to see what works best.

If you use git, make sure your commit messages start with a single line, under 72 characters, which provides an adequate summary of your changes. You should prefix this line with the component you are committing (for example, ``map17: fixed unbeatable map''). This should be followed by a blank line and a paragraph or more to explain your change in detail (for example, explaining what part of the map was broken). See commit 27762aa5f34f590bfc29d1f667f9121907cb8a98 for an example. Sign your comments with `git commit -s`, these leaves a trail of whose hands a commit went through and could be useful for some purposes; git alone can give an indication of up to two people, however the AUTHOR/COMMITER fields are not quite reliable or flexible enough for the same information.

You should commit often; each important change should get its own commit, but minor changes need not. Take advantage of git’s ability to rewrite history, don’t use `git revert` on your private copy of the repository, just remove (`git reset`) or amend (`git commit --amend`) the faulty commit as necessary. Leave all the interesting and important history bits, leave out stupid mistakes like spell check errors.