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Branching Out

September 18th, 2006 by Multimedia Mike

Cyril Zorin wanted a good place to document a 3D model format used in a LucasArts computer game. I thought this might be a good time to expand the charter of the MultimediaWiki to include more general game formats, not just the FMV-oriented ones. That is, unless there are other wikis devoted to that same charter. Perhaps I’m not asking the right questions, but a quick Google for “game format wiki” brings up this domain and the XentaxWiki in the first page.


joystick

BTW, Cyril wants to know if anyone has anything to add to the inaugural 3D format page in the MultimediaWiki.

Posted in Game Hacking | 7 Comments »

7 Responses

  1. schwarzmaler Says:

    A “more proper place” possibly be

    http://rewiki.regengedanken.de/wiki/Main_Page

    It’s not that advanced (yet) and there’re not many people submitting.
    But I guess there are just not THAT many people into reversing actual game formats ;-)
    (or people that have heard of the Wiki ;-)
    [Yes, there is actually content =p]

    Just take a look and tell if it’s a ‘good place’ for it in your oppinion.

  2. Multimedia Mike Says:

    Thanks. I knew I had seen that Wiki once before when it had just started out. But I couldn’t find it again. If there is already a well-maintained Wiki focused on game topics, I would rather support that.

  3. jsg Says:

    Games not game. It is actually the format of the renderdroid (Jedi Knight) engine. The ASCII version was somewhat documented with several modelling programs that can manipulate them. Quite some time ago I started documenting the binary format by comparing the demo (still ASCII at that stage) with the final version of Grim Fandango (binary), and wrote up a bunch of notes. Sometime after other people who tinker with LucasArts games expanded on them.

    Code that interprets the binary format and other related bits can be found in the Residual Grim Fandango engine (GrimE) reimplementation.

  4. Cyril Says:

    jsg, the Residual code that interprets the binary format is incomplete. We’re looking to make a complete spec to know exactly what each piece of the file is for. Right now we’ve mapped all fields from the ASCII format to their binary counterparts, but there is more data that’s still being looked at. If you can help, help.

  5. jsg Says:

    http://www.lucasforums.com/showpost.php?p=1264637&postcount=7 has an updated version of http://goblin.cx/grime/grim-3do.txt for what it’s worth. Beyond what is in those now several years old documents I can’t really help for lack of time and memory. I do believe that John’s 3do viewer was at least starting to interpret the models from Monkey Island 4, which uses the same engine, so the format can’t have changed overly much.

  6. malc Says:

    Not sure whether this is of any interest(relevance). But at
    http://www.boblycat.org/~malc/code/ one can find “documentation” (in source-code form mostly) for Bioforge/Origin and Outcast/Appeal.

    http://www.boblycat.org/~malc/okaar/outdoc/list.html contains plain text description of animations used in Outcast, and i belive i once described meshes to someone over the e-mail and can probably dig it up should anyone be interested.

  7. john_doe Says:

    @jsg:
    GrimE, which Grim Fandango uses, and the EMI engine are quite different, file-format wise.
    The very old viewer only displays single model parts, not the whole model.
    I made an improved version (based on the EMI model viewer) that displayed the full textured model and had early animation support. I used the Residual source code as a reference. Since it’s just a viewer a lot of stuff is not used, i.e. bounding box/sphere stuff etc. (if there’s something like that at all).