Annali da Samarcanda

Alberto Marnetto’s Notebook


Contents

Grand Prix Circuit

Don Matrelli’s Legacy

Don Matrelli’s Legacy is a mod featuring:

For more images and videos, see the release announcement.

image     image

As for any good game of the past century, reading the manual is an important part of the experience.

Stressed – GPC edition

The tool stressed (STunts RESource EDitor) is an application by Daniel Stien (“dstien”) allowing to edit the resource files of various games developed by DSI. Here we present an extended version supporting the .PES files of Grand Prix Circuit. Further developments targeting .PCS files (CGA graphics) and Test Drive might be possible in future.

Note: Set Options / Compression Format to the correct value before opening a file.

Vehicle editors

There are two editors able to customize the performance of Grand Prix Circuit’s cars.

cyclesmod

cyclesmod is a Java tool by “albertus82”. It works by patching the GPEGA.EXE executable and creating a new one with the modded cars

gpc-vehicle-edit

The tool used to develop the cars in Don Matrelli’s Legacy. Made in C++ and Qt, mostly vibe-coded using cyclesmod as base. It reads and writes the 444-byte array containing the data of the three vehicles. One can start with an empty array, or extract the baseline from a dump of the data segment when the game is running:

dd if=data-segment.bin of=vehicles-array.bin bs=1 skip=$(( 0x75f2 )) count=444
 
The McLaren engine data in the base game. Notice the innatural boost between 9 and 10 krpm: likely a last-minute adjustment by the game developers.

Comments

No GitHub account? You can also send me your comment by mail at alberto.m.dev@gmail.com