Meeting 2021-02-18

[XAMPPRocky]

Where & When

• #rust-gpu on the Embark Discord.
• Time: 17:00 CET
• Previous Meeting

Agenda

• Project updates
• Review & discuss any open MCPs
• Discuss Compile shaders at runtime #423

Feel free to propose additional items in this thread.

[XAMPPRocky]

Project Updates:

@Jasper-Bekkers: Byte address buffers

• I haven't checked the SPIR-V
• the parameter loading is the offset in bytes aligned to word.
• The traverse engine has switched to fully bindless.
• Glad I got my PR merged.

@eddyb: Now I have to make it work with my stuff 😄

• It's not too bad, I just need to update some code in tests.

@Jasper-Bekkers: One things that is a non uniform resource asset. Where instead of a uniform lookup and index, you can get a nonuniform one.
@eddyb: I don't think that interacts with storage class inference.
@Jasper-Bekkers: Probably not.
@eddyb: There are some todos, and it's to easy to trigger by disabling DCE.
@khyperia: Those shouldn't be blockers though.
@eddyb: It just makes it easier, I think I have a path forward.

@khyperia: Mostly working on Ark.
@VZout: Same
@Jasper-Bekkers: Making pr
@XAMPPRocky: Added documentation around inline asm, added OpImageRead/OpImageWrite and StorageImage type.

MCPs:

#429

@XAMPPRocky: I'd for us to start using completest for tests, it has a variety of features, and importantly it should enable our tests to be able to run parallel rather than serial.
@khyperia: Seems good.
@eddyb: Might need to figure out codegen tests, as that uses a LLVM tool.
@XAMPPRocky: Supporting other codgen might be nice a addition to compiletest if it doesn't work out of the box.

Other

@Hentropy: Regarding #423

• So this would provide significant compile-time benefits, but there needs to be logic copied from spirv-builder into the compile_shader function? Does that seem okay?

@khyperia: Yep

@Hentropy: should the ash runner be moved to a test runner from an example runner?
@eddyb: We could have a common crate for applying events from the Window, and for headless we can just pass PushConstant with some values.

• Doesn't need to be complicated.
• You can keep all the ash rendering code, but that's it. It does get tricky with UniformConstants

@Jasper-Bekkers: As long as the ash code is run I don't see a problem.

@XAMPPRocky: Should we have a nominated label for tagging anything you want to discuss at the next meeting?
@khyperia: Seems good.

@Hentropy: Has there been much though into how to share CPU and GPU code.
@VZout: We've been working on some different approaches internally in Ark.
@XAMPPRocky: Of course, if other people have ideas, please share the code.