TOMB5

A 3-post collection

on TOMB5, PSX development, Programming • 2 min read

Fix for the Psy-Q Saturn SDK

If you ever want to write code for the Sega Saturn using the Psy-Q SDK (available here), you may encounter a small problem with the toolset when using #include directives.

Example:

#include "abc.h"

int main()
{
    int b = a + 43;
    return 0;
}
main.c
C:\Psyq\bin>ccsh -ITHING/ -S main.c
build.bat
int a = 98;
abc.h

This will crash with the following error: main.c:1: abc.h: No such file or directory, which is quite strange given that we explicitely told the compiler to look in that THING folder.

What we have:

  • CCSH.EXE : main compiler executable (C Compiler Super-H)
  • CPPSH.EXE preprocessor (C PreProcessor Super-H)

CCSH calls CPPSH with the source file first to get a raw code file to compile, and then actually compiles it. Here, we can see by running CPPSH alone that it still triggers the error, which means the problem effectively comes from CPPSH. After a thorough analysis in Ida, it seems that even though the code that handles parsing the command-line parameters related to include directories, those paths aren't actually added to the program's internal directory array and thus never actually

on TOMB5 • 2 min read

TOMB5 - Feb'19 status update

The project has come a long way since June of 2017.

Since the beginning of the project, the codebase has been divided into two separate branches: PC and PSX, which share a common "GAME" folder which contains the platform-independent game logic code.

More progress has been made on the PSX version since a lot of code is plain old MIPS assembly which we haven't had to decompile to C, so the PC version is still lagging behind. Problems with the old DirectX version used by the game (DX5) makes all of this much harder.

Also, debugging the PSX version has always been a pain in the ass because of the need to run it in an emulator (we've used no$psx most of the time).

To solve that problem, we've started working on what we call the Emulator, which is simply put an implementation of the PSY-Q PSX SDK acting as an HLE emulator for the game. That way, we can debug the game directly in VS which is quite appreciable. We simply need to link the game binary against our emulator DLL instead of the standard PSY-Q libs. The emulator is based on SDL for windowing and OpenGL for

on TOMB5, Programming, PSX development • 2 min read

Paella, or how to emulate PSX games in Windows CE userland

Lately, I've been decompiling Tomb Raider 5 with some friends and while researching potential sources of debug informations that could help the process, I stumbled upon the Pocket PC version of Tomb Raider 1. It was ported by Ideaworks3D, a London-based game development company specialized in porting.

It's supposed to run on low-performance handheld devices running Windows Mobile/CE 5.0 and thus one would imagine that they have simply taken the Windows code and tweaked it a little bit to make it run on CE. Well as I discovered, it's more complicated than that. First, there is no Windows version of TR1, it was only released for DOS and was never ported to either Win16 or Win32. Second, they actually didn't take the PC version as a base, but the PSX version.

It may seem weird, why take the PSX version if your product is going to run on Windows CE. As it appears, Ideaworks3D seems to have developed an in-house userland syscall JIT translator for PSX, and uses it when porting games to CE. In other words, they compile the PSX codebase to ARM code and link that binary against a DLL file called iepaella.dll which contains