Linux in a Pixel Shader – a Risc-V Emulator for Vrchat
Posted2 months agoActive2 months ago
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Risc-V EmulationGPU ComputingVrchat
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Risc-V Emulation
GPU Computing
Vrchat
A developer has successfully emulated a RISC-V CPU and run Linux within a pixel shader in VRChat, showcasing impressive technical achievement and creativity, with the community praising the work and exploring its implications.
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p.s. Udon Bird Sanctuary! I've been there!
On the other hand horizon is super restricted in what you can do, is way too heavily moderated and rubber tiled so it's not fun to be in there at all. VRChat is way better at finding the edge of what's possible. I've seen whole worlds from half Life 2 recreated etc.
Granted, the last time I touched it was a few years ago. Unless they've done a major rewrite of the game I don't expect it to have improved all that much. Maybe I'm wrong.
VRChat is not perfect, it has a lot of rough edges. But it's buzzing with activity. People enjoy themselves. Do sometimes weird stuff but not bother anyone. It's like the real world.
Horizons is a boring moderated infantile playground. I guess they're super worried some conservative senator's grandchild hears the F word there and is scarred for life. But in mitigating this they have eliminated any attraction to the whole product. Us adults, we need a little gritty. It's why we don't watch Kung Fu Panda when we're not with kids.
For example I found a few rooms where people go to sleep around others when they're lonely. Complete with a calming environment. I haven't seen anything like that in horizons. Just some attempts at mildly boring games and funhouses.
Also the furries have a home there which works fine. I've never seen anyone with 'anatomically correct' avatars in the wrong space. It works and they have fun. That's what it's all about, human connection.
I found a world like that when I searched for one a couple years ago in horizons.
The more technically impressive worlds don't just use the VRChat provided object syncing or interactions, they create their own systems tailored to the world, but Udon, the world scripting language, is sluggishly slow, 200X-1000X slower (according to VRC themselves and I know is true from experience), compared to ordinary scripting inside Unity, which means the only ones able to make their own systems are not only good at coding, they are really good at optimizing, on a generally amateur creation platform like VRC those people are very few.
They are trying to recreate Udon to be more performant, but small company and their first attempt was discarded after the sole employee working on it was let go.
Network delay could be considered another thing holding back mini game creation, but even if the network stack was better, you have people all over the world, latency will always be an issue.
The closest to compute shaders we have are camera loops using render textures and AsyncGPUReadback which has been limited to only handle inputs and outputs in the form of textures.
Also the reason why it is even done in shader is because the scripting language in VRChat is 200X-1000X slower than normal Unity scripting, with no async or way to do threads.
Work like this highlights how different the compute models are between gpu and cpu. Honestly very impressed it runs as fast as it does (250khz) given those differences.
i'm not saying people should do that, but would it be possible?