[dnlfern]

Hi all. I hope I’m posting this in the right place so my apologies if not.

At the moment, I’m enjoying playing a lot of older games through emulation - be it those that I haven’t experienced before, or some that I just want to replay.

I’m also a fan of retro computing - vintage macs, dos / early windows and the like. Lately, the Silicon Graphics ecosystem and IRIX has really peaked my interest. However, only to find that the development scene for the MAME emulator for SGI has basically ground to a complete halt. Finding this out got me thinking…

For my day job I’m a mobile and web developer so I write a LOT of JavaScript and various other languages too - swift etc. But I’ve recently taken an interest in learning C++ as something that’s a bit more of a challenge for myself.

So my question is this… how do I go about getting started in the development side of the emulation scene. I think it would be a really good fit with my wanting a new programming challenge. I’m especially keen in being part of the IRIX on mame project but to be honest I just want to get stuck in and start working on something.

any help would be very much appreciated

[Raion]

A good start would be studying the mame Indy driver code and how it operates.

Once you got an idea of how to improve it, join the official MAME channels and connect with anybody else working on it.

Of course it would be really good to have more people who can advise users here of how to improve their experience but as of right now the issue with MAME is the lack of a jit for MIPS.

Now, the MIPS CPU in the Indy is very similar to the R4300i in the N64, so a good idea would be to study that code as well and figure out how to apply what you've learned there.

Besides that, the other way to open IRIX access would be working with the community here to write drivers for commodity hardware and/or reverse engineering parts of the kernel for use on another platform. One of the long sticking points was related to the graphics hardware for the Indy, unfortunately basically all other graphics cards are very poorly documented so you might not have but so much luck trying to emulate them.

It's also probably worth getting some hardware at some point so that you can actually work with the real hardware and use that as a cross comparison.

[dnlfern]

Thanks Raion! 

That’s a lot to go at, and definitely a brilliant starting point for me, and a lot more than just a starting point too. Thanks again! 

Real hardware is definitely something I want to get at some point but it’s not financially in the cards at the moment. Hopefully soon though.

[Raion]

I can certainly understand your personal situation; as I too have had bad financial situations prior.

Hopefully that provides you with the information to get started. My personal interactions with some members of MAME has taught me it's better to be prepared because a lot of them are absolutely ruthless with people who pester them with questions that are in the code/comments/docs.

[weblacky]

While I'm definitely not the guy to ask about this exact topic I would say that you should remember that Linux & BSD, at one point, ran on several SGI platforms so it might be worth it to look into that and work backwards. I'm not saying that Irix and Linux have exactly the same requirements, but at least you would see what on the MIPS hardware side had to be set up to run an operating system at start. That might lead to educational value about learning the specifics of the hardware you're trying to investigate.

From my knowledge there isn't a single game on Irix that isn't available for another platform. So gamers really shouldn't be interested in this platform at all for gaming. My personal opinion is, for all intents and purposes, SGI machines are often single task systems designed to do one thing and one thing well depending on the application you're running. That's not to say they don't fall into the general computing category but the way they were purchased and utilized was not in running five or six different things it was often for a very specific application or very specific workflow of applications either in the 3-D modeling, image manipulation, video rendering and post-processing, or simulator industries. I always felt that IRIX as a desktop was anemic enough where you at least had basic email and the earlier web browsers did function so you could do the rest of your work on it outside of the one thing you were supposed to do it work with your SGI which was one of the above. But the platform just barely met the general office requirements for a worker doing a specialized task.

As a piece of history there's no question they're cool. They were often bought and used for very specific purpose, only. And back then the pace of technology was moving so fast that their expected lifespan wasn't more than a few years before the next big thing with supplant it twice as much power or more. SGI's fell into that very thin and niche segment, where you needed to perform a task that was a huge moneymaker and you could make your money back in a year or less from the system's purchase doing whatever it is you needed done. Because in three years, maybe four, that station would be totally obsolete compared to what would be available.

[Raion]

People have tried this with GXEmul, and the fact remains that those can boot in a hacked up emulator much easier than IRIX. MAME didn't work that way, Ryan (one of the main devs) was a friend of mine for a while. His methods, AFAIK, were RE and using existing docs.