Jam Editor

[github.com]

I've released a 'new' version of Jam Editor - long story short, various mods and interests for GP2/GP3 made me want to fire it up again.

Was mainly hoping to convert some of the Belini tracks over to software mode, as the software mode generally runs better/more efficiently these days over GP3's D3D mode. Turns out it's not as simple as that.

What started as an attempt to create a batch converter spiralled into building some sort of proper Jam Editor... And after what I can only describe as a feable effort/juvenile/bug ridden effort back in the early 2000s by myself... 20 years on, a slightly wiser head has tried to right the wrongs & have a bit of a personal project during what I can only describe as the biggest lull I've had in my career.

There was an open source group years ago and sadly some of the code was lost, as was my original Jam Editor despite a bit of searching of old hard drives.

Paul Hoad released his code for Track Editor and Car Shape Editor - made me realise we'd lost the Jam side of things too... When I was getting stuck in I realised the workings should also get shared as it could easily be lost!

Thankfully my 'career' work has picked up but as a result I've not touched this 'project' since September...

So I've decided to release what I have and the source code in case anyone wants to have a butchers/pick it up. It's not the best so please don't judge me - I don't code for a living! But hopefully it means there's some live/open source code of both SW & HW Jam decryption out there.

Trevor Kellaway's Github source, was invaluable during this process - [github.com].

Highlights of what I've tried to build:

- Proper SW palette generation
- Jam Browser
- Batch Convert
- RCR Jam reading attempts - I realised Geoff implemented a form of vertical interlacing to generate x2 sprites in one image. Never realised it back in the day...

I was going to try and build a process for JIP creation but have not got round to it... I might try and add this in due course, depends on the interest.

And yes... as I write this, I've just seen Microprose's announcement of the re-release of F1GP-GP4. What a time to be alive

All the best,
Jim



Edited 3 time(s). Last edit at 12/17/2025 09:42PM by jamesknopp.

Thanks Jim, am I correct in understanding that the project is incomplete? As a software mode user myself it would be incredible to have a tool as you described. Do you remember what are the main difficulties of the convert?

Thanks for your efforts, and its incredible to have Sir Geoff back in business



FORZA FERRARI

Hi jamesknopp

I read in your post.... Did you lose your original Jam Editor?

Could this be it?

=> "Jam Editor Version 1.6b" made by James Knopp on 01-05-2002

Here's yours and two more..... [Mediafire]


I didn't quite understand your post...

It would be a new tool, since I don't understand programming code.

It would be very useful to have a JIP file editor, as I would really like to create some images for old racetracks, like putting Cinzano on the Imola asphalt...

See my post on this subject here

Evandro ( Brazil )

GP2tifiso28 Wrote:
> Thanks Jim, am I correct in understanding that the project is incomplete?

Yes. There's some bits missing/some issues - but the batch conversion works. It will convert HW JAMs to SW. But some of the JAMs crash the game - for example Belini's Hockenheim 2000 track I probably got 80% converted to Software but there were issues with some JAMs not loading/crashing the game. I think it's partly a size issue, sometimes the overall canvas dimension/texture dimension issue as some of the JAMs are much larger in height dimension.

It's not a simple case of batch converting and/or resizing textures, then expecting them to map on objects the same way. Some of the advert JAMs I ended up splitting up into other JAMs and added them to the track .dat file which was moderately successful. That says to me the limit on software JAM's canvas height is possibly 384 pixels, but haven't fully tested it out.

evroic Wrote:
-------------------------------------------------------
> Hi jamesknopp
>
> I read in your post.... Did you lose your original
> Jam Editor?
>

I lost all the source code - was a long time ago! Plus what I sent out was a buggy mess... I hear you on the JIP issues. I have some ideas on how to approach it but haven't had the time to develop!

[drive.google.com]

JIP generation now here - import textures, not canvas is the best approach. Principle is to import individual items, they are then positioned as best as possible for the canvas, plus the mipmaps are generated fully by the app.

Some interesting RCR JAM generation too.

Amazing work & kudos from Comick on the browser related Jam Editor!

If you find a bug or problem, please tell me step by step what happened, along with associated files and I'll do what I can to fix.

Cheers
Jim



Edited 1 time(s). Last edit at 05/14/2026 08:42AM by jamesknopp.

[github.com]

Small update - Jam/Jip association option, fixed some issues with auto JIP generation.