What just happened? For gamers of a certain age, few titles hold as much nostalgic appeal as the original Doom. Now, nearly 30 years since it first came out, the classic FPS has achieved another impressive milestone – being ported to run on quantum computers.
The mind behind the endeavor is Luke Mortimer, a PhD student at the Barcelona ICFO Institute who is well-versed in quantum information. In the release notes on GitHub, he jokes that Quandoom could be “the first practical use found for quantum computers.”
Before you get too excited about blowing up demons to bits on a cutting-edge quantum computer, there’s a pretty big catch. Unfortunately, we happen to live in a reality where those machines are still possibly decades away from going mainstream. Even the billion-dollar tech giants betting big on quantum computing wouldn’t be able to get this port up and running on their experimental rigs sitting in secure facilities right now.
That’s because Quandoom requires a whopping 72,376 qubits and 80 million logic gates to run, according to Lumorti’s notes. For some perspective, IBM’s current flagship “Osprey” quantum computer musters just 433 qubits – with plenty of errors.
DOOM on a quantum computer … pic.twitter.com/MKLuwimgPN
– Prof B Buchanan OBE FRSE (@billatnapier) September 30, 2024
Thankfully, the game has a workaround to get it up and running on today’s more humble technology. By using a lightweight QASM simulator, the code can achieve a playable 10-20 frames per second. You’ll have to download the files from GitHub and drag them over into “simulator.exe.” The developer adds that because the circuit file is rather large, the game will “use about 5-6 GB of RAM and take a while to load.”
There are some other limitations too. The visuals are a stark wire-frame “X-ray mode” due to what Lumorti calls “reversibility shenanigans.” There’s no color, no music, and no secret rooms.
Still, the effort proves that if we do end up achieving quantum supremacy, Doom will likely be the first thing those people in white coats try.
Lumorti seems to have poured a decent amount of effort into this project, with over 8,000 lines of C++, a custom 3D engine, and more. The game itself is a recreation of the first level of Doom from scratch. And while the source code isn’t available yet, the developer has provided steps for tinkerers to compile the code themselves.