Bringing New Life to Games with Carbon
February 09 2022
There’s always something new happening around the hallowed halls of Limited Run Games. Lately, a lot of the internal buzz has been around the Carbon Engine. What’s a Carbon Engine, you ask?
Development Lead Joe Modzeleski has been porting games at Limited Run for a long time, and a lot of his work nowadays is on bringing games to life with Carbon. But in typical LRG fashion, our conversation first strayed into game enthusiast and collector territory
LRG: Before we get to the main part of the article, what's the current state of your garage arcade?
Joe: I'm completely out of room! Just yesterday I finally got my Simpsons cabinet working, almost a year to the day after picking the thing up. Working on restoring and maintaining these arcade cabs has basically become my “dad project,” and I don't know when I'm going to stop. I love classic score-based arcade games and fighting games so there's a clear pattern to the games I've been picking up. I have 13 games, not including the pair of Daytona USA cabs that I own but that aren't currently in my garage, and one pinball right now. I have Donkey Kong, Donkey Kong Jr, Mario Bros, Playchoice-10, DDR Solo 4th Mix, Crazy Taxi, The Simpsons, NBA Jam (+ Maximum Hangtime), Neo Geo MVS, TMNT 89, Mortal Kombat II, Street Fighter II (+ Marvel Vs. Capcom), Killer Instinct (+ KI2), and The Simpsons Pinball.
LRG: That’s... a lot.
So let's talk about this Carbon Engine... just what exactly is it? What does it allow you to do?
Joe: Carbon Engine is our internally developed tool that basically helps different emulators interface with modern hardware. We have a variety of emulators we're currently using and building out Carbon Engine to support, including a mix of both internally developed emulators and licensed ones. Carbon Engine is a multi-platform development tool that handles things like UI, rendering, audio, data management, controller inputs, console specific SDK features like trophies, etc, and allows us to build out emulation-based releases of classic games for modern hardware. As we build out the feature set, Carbon Engine games are going to get access to a rapidly evolving set of features.
LRG: So it’s, like, emulation? What distinguishes it and makes it special?
Joe: It's emulation. We've both built our own emulators from scratch and licensed a variety of emulators to build out what Carbon can support. The team working on Carbon all really care about game/hardware accuracy and that care dominates every decision we make. What makes it special is that unlike a straight port of an emulator, this uses a lot of centralized tools and features that can be utilized across multiple emulators and multiple pieces of hardware.
LRG: So what are you doing with it? What Limited Run Games is Carbon a part of?
Joe: We're working with our partners to give them a pipeline to re-release their legacy content. The amount of investment to get a project like this done is pretty high for a one-off release, so we are using it to mitigate that financial investment that has served as a blocker from making a lot of legacy software viable to re-release. So far we've completed two titles that use Carbon: Shantae and River City Girls Zero.
LRG: What's a Carbon capability you're really grateful for?
Joe: We've got a lot of capability to debug classic games, not to alter them, but to piggyback off of information to do things that help provide a more modern user experience, and I think that's really awesome. Something like in River City Girls Zero for example, where we're able to hijack bits of memory on the mode select screen to prevent the player from selecting a 2-player mode while they're playing their Switch in handheld mode, or to read bits of memory from the game in real time to prompt the player on when they should connect or disconnect extra controllers. It's a lot more seamless than using an off-the-shelf emulator as-is, and I think things like that will let us make the experience of playing these games better without compromising anything about the title itself.
LRG: What's something working in Carbon taught you about old games?
Joe: That making games in the 80's and 90's was really complicated! The most simple things about making games today I have taken completely for granted. Stuff as simple as drawing sprites and tiles to the screen are really complex and require a ton of proprietary knowledge for each bit of hardware we're emulating. I've got a lot of care and a good sense of how a lot of these games should look, sound, and feel. I'm on the light end of being a retro snob I guess, but the thing that has always been missing before Carbon about my care/knowledge of older games is the experience of what using that hardware was actually like. We don't even have to make games from scratch—just in emulating them we've learned so much about the hurdles older developers faced!
LRG: OK, so I know you, and I have to ask, on the record: Why do you persist in remaining a classic Killer Instinct apologist?
Joe: Because I have impeccable taste.
If you want to see Carbon in action, be sure to pick up River City Girls Zero, available now to pre-order! Want to know more about it? Listen to last week’s Runtime podcast with WayForward’s Adam Tierney!