Nicking assets from Tachyon: The Fringe, Part 1: Why and What

Intro

Many of the projects I’d like to do in my non-existent off time involve game development. I want to create an RTS, or a Fighter sim, or similar, but I inevitably run into a problem that’s always been a stumbling block: All these projects at some point call for shiny 3D assets. And I’m a programmer, not an artist. How can I get 3D assets to start development with?

I could look for free assets online, but I always find that kind of hit and miss. You have to spend hours upon hours to find a few good models, all in disparate formats that then need markup and corrections. It’s a mess that zaps my desire to live and my desire to do development.

I could pay someone money to generate models and textures for these games that likely won’t get past the weekend project phase. This still has the problem that I’m not an artist, so the requests would come down to “make me a cool looking spaceship”. That’s destined for disappointment.

OR. I could nick assets I already like from a game.  And not just any game, but the best game ever: Tachyon: The Fringe.

Disclaimer: In case you can’t tell, these are soley for personal non-commercial projects. It’s me trying to ease the path to getting something interesting on screen so that I can keep momentum up.

Starting Info

Tachyon, the best game ever, is a Space Combat Simulator released in early 2000. It’s actually still available today via Steam, though I’m sure no one at Nova Logic has touched the source code in the past 12 years. There’s been one notable project to try and modernize it, the fan made FringeSpace total conversion for Free Space 2. As of this writing that’s still ongoing (and I think I read they’re in their 6th or 7th year). One of their first projects was extraction of model data, but for whatever reason they had a lot of issues with that, and instead went the route of re-creating the assets by hand.

The original attempt at reverse engineering the model formats is semi-documented here (see Development Log, mid way through, apparently a copy of a LiveJournal of a fellow named Stuart Stanfield from 2002). Without this as a starting point I would not have gotten as far as I have. This is my first attempt at reverse engineering a binary file format, and that dev log is a good introduction for getting into the right mindset.

Tachyon stores assets in a single ~400MB pff archive. The PFF format is something common across NovaLogic games, shared by TTF and (the early) Delta Forces. It’s effectively a tar file- contains a set of records and the unencoded/uncompressed file data in a single archive. (apparently later versions of PFF support compression of data, but that’s not something we need to worry about).

The models in the PFF archive are stored as PAKs (for small things / single ships) and OCFs (for stations, capital ships, other). The PAKs contain model data, image data, and minor rigging information. The OCFs combine a set of PAKs in a tree format, basically like a standard hierarchical skeleton.

What to Expect

The next part in the series will be looking at the individual file formats. Really most of what I’m looking to do with this series is document the format and process so anyone else can do the same. I hate it when information is lost because it went unshared, especially in this day and age- there are quite a few tools out there, people have clearly spent time on this, but very little source code makes it out into the wild.

My end goal is to build a model viewer/exporter, to look at all the shiny PAK and OCF assets and export them in a more friendly format. This’ll be in C# as I prefer it for building tooling that calls for a GUI. I’ll post the end result on Github for all to consume, and hopefully not be C&D’d.

A lot of the work is already done (I’ve already built individual PAK and OCF viewers, but they’re a bit rough around the edges, so I’m redoing bits of the UI) (and it’s not yet in GitHub/public), so this is mostly a retrospective, though there are still a lot of unknowns I’m hoping to solve.

Update:

Code is available on GitHub at: https://github.com/codertao/TTFModelViewer . The code includes everything I’ve done up until now, so, it’s semi-complete, but not that clean.

Leave a Reply


Allowed HTML:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>