FULL STORY
Dev Emulates a Full PC in VRChat Shaders, Runs Quake 3
Michael Moroz's open-source ShaderEmu simulates a full 32-bit RISC-V PC inside VRChat pixel shaders, booting Linux and Doom, and has since been extended to run Quake 3.
2026-10-07 ~ 2026-10-17 · 3 episodes · 7 posts
Episode 1 · Developer Emulates RISC-V Computer in VRChat Shader, Runs Doom (2026-10-07, 3 posts)
Michael Moroz's open-source ShaderEmu emulates a 32-bit RISC-V computer inside a pixel shader running in VRChat, achieving a working window manager, playable Doom and a basic browser after two days of automated optimization by Claude Opus.
- Opus 5.5 spent 2 days optimizing a RISC-V emulator in a shader to run Doom — Michael_Moroz_ · 2026-10-07
- VRChat shader computer now runs a limited browser alongside Doom — Michael_Moroz_ · 2026-10-07
- Dev emulates an entire RISC-V PC inside a pixel shader, aiming to run Doom in VRChat — Michael_Moroz_ · 2026-10-07
Episode 2 · Dev Runs Quake 3 and More Inside a VRChat Shader (2026-10-17, 2 posts)
Michael Moroz has pushed his VRChat fragment-shader emulation further, now running Quake 3 Arena with VR controls and LAN play, alongside an expanding 'PC' setup that includes IDEs, physics simulation, path tracing, browsers, and media playback.
- Quake 3 now runs inside VRChat via fragment shaders, complete with VR controls and LAN play — Michael_Moroz_ · 2026-10-17
- VRChat shader PC now runs an IDE, Red Alert, SimCity, a path tracer and more inside fragment shaders — Michael_Moroz_ · 2026-10-17
Episode 3 · ShaderEmu boots Linux inside VRChat using only a pixel shader (2026-10-17, 2 posts)
Developer Michael Moroz open-sourced ShaderEmu, a 32-bit RISC-V computer emulated entirely in a pixel shader that boots Linux in VRChat, and says Half-Life could theoretically run too, though using a GPU as a CPU is extremely inefficient.
- Shader-PC author: Half-Life should run too, but GPUs are terrible at emulating CPUs — Michael_Moroz_ · 2026-10-17
- ShaderEmu Boots Linux Inside a Pixel Shader, Runs Doom in VRChat — Michael_Moroz_ · 2026-10-17