Reversing Grand Prix Circuit

[HerrNove]

Ryoma has used the new `stressed` to create an edition of GPC that reproduces more faithfully the 1988 season:

https://www.youtube.com/watch?v=JqtWVCGKUnE

[HerrNove]

The mod is approaching completion. Here a preview with a new car on a new ( but actually quite old  ) track

https://www.youtube.com/watch?v=f4_90RCFmcE

[HerrNove]

Mod published (see the other thread). I also published the extended verion of Stressed allowing to open GPC files. Hope it will be merged to the official edition soon.

https://marnetto.net/projects/grand-prix-circuit#stressed--gpc-edition

[alanrotoi]

By the way, if there is a project that can mod something from Test Drive 3, probably those tools could work with Grand Prix Unlimited too, since they are very similar games. GPU may be a game with a terrible handling but it has a track editor. A much more comprehensive track editor than Stunts'.

[Swift_]

Friendly greetings to everyone from Hungary, it's my first time posting here

I haven't found any other place online about reverse-engineering GPC, so I registered specifically because I'd like to share my own documentation for the music and voice formats used by the DOS version of GPC and TD2.

You can access the ongoing music/voice reverse-engineering project through this Github link: https://github.com/Swift97/testdrive2-music/
(Don't mind the project name. It started as a SONGS.BIN doc, but GPC's MUSIC.BIN uses the same format.)

It took a lot of trial-and-error experimenting with Dosbox/Hex Workshop/Audacity/FL Studio, as well as a small bit of LLM usage to auto-scan through the GPCEGA.EXE and TD2EGA.EXE files in order to verify/cross-check my findings (especially about the pattern roll's control/event bytes). The result is a documentation that's proven and tested to be effective for both games.

As you can read in the preamble/README, updates may be slow, but I try to update the .MD text files as soon as I figure out something new about the format. I have to juggle IRL matters, other hobbies, work, fooling around with TD2's .PES/Car/Track data, etc. along with this project.
Also please bear with my terrible formatting scheme. I tried to make it as logical and easy to read as I could, but I've never written any docs like this.



I really hope it'll be at least a little useful to someone who might stumble upon it in the future Maybe someone will create a cool Famitracker-like sequencer. Or maybe someone will program a sick original song with arps and pitch bends defined with different voices, perhaps a remix of the GPC theme itself

Lastly for fun, here's the main riff from Doom E1M1 hand-coded in Hex Workshop https://youtu.be/l2IkhIS0ZVE

[alanrotoi]

Congratulations! It sounds quiet good and funny!

[HerrNove]

Great find! Developer Roel Derickx had published some initial research on the music (https://github.com/roelderickx/retro-grandprix), but your work is the first one that really documents the format. Also, At Doom's Gate is a really fit replacement for TD2's start menu.

[Zapper]

Another recent finding about sound and music modification on GPC:

https://youtu.be/LUjgzxsvFYA


Can this somehow be related to any previous post messages?