Meeting 2020-11-05

[arirawr]

Previous meeting: #144

Time: 17:00 CET
Where: #rust-gpu voice channel on Ark Discord.

Agenda
(please edit/add)

• small intros
• @khyperia project update
• recent contributions, things in flight
• 0.2? 😮
  • also, release process/frequency/publishing
• build system bikeshedding 😛

[repi]

Meeting notes

Participants

• @repi
• @khyperia
• @VZout
• @Jasper-Bekkers
• @Jake-Shadle
• @arirawr
• @XAMPPRocky
• @termhn
• Additional guests from Discord!
  • @nolanderc
  • @msiglreith

Minutes

What are we working on

• @termhn Converting Ark shaders Convert all Ark shaders to Rust GPU #36

  • Been going pretty well so far.
  • Started with mesh shader, if it works then most of our features that we need will be in place for our other shaders also
  • Will make list of what compiler features we need
  • Also wrote up an issue about color conventions, not directly related
  • Can't do "buffer blocks", multiple uniforms in one buffer
    • @khyperia May be very easy to hack in support for it

• @Jasper-Bekkers Doing RFC on inputs/outputs on shader stages (link?)

• @MarijnS95 working on Android, works fine! Tracking Issue for Android Support #190

• @khyperia Build systems, compiler fixes, bunch of stuff in flight

• @VZout continuing working on structurizer

  • Bug: two if statements in a single function
  • Switch statements is not supported yet
  • May get some help on the irreducible -> reducible spirv paths
  • Fixing bugs right now
  • @nolanderc asked if can help, probably not at this point

• @repi Did an experiment with hot-reloading of shaders in example

  • Works really well and is surprisingly nice even in our small examples
  • Still embeds the initial shader in the executable, but then uses cargo watch and monitors the target folder to reload the .spv files
  • Will do draft PR

• @XAMPPRocky Build system.

  • How things are built with rustc
  • Also building our own sysroot. nice cargo-sysroot crate
  • New spirv json file? @khyperia: shouldn't be needed
  • Don't need spirv-builder. hopefully

rust-gpu 0.2?

• Do a proper next release with release notes as mini blog post and new screenshot(s)

• Target: Mid December

• What to include/require, @khyperia: "everything gray requests for parts" (to bring up the Ark shaders)

• Publish our crates on crates.io? Yes, to be able to build without git dependency

• Maybe compute shaders if it is in

  • @nolanderc wants it also
  • @khyperia: GL/Vulkan or OpenCL, (answer: GL/Vulkan)

• spirv-std. yes. writing shaders without

• maybe not spirv-builder? May have different build system

• backend-cranelift crates.io is a rustc binary front-end

• Get some more example shaders

  • once textures are in @khyperia will re-write her raytracer in.
  • @VZout will add his shaders
  • Potentially could include some of our Ark shaders as well, nothing too special but good test cases

• Want match/switch statements

• Generally positive to to people to have these versioned releases, get some roadmap

  • Provides some timelines
  • Good way to communicate out to the community and engage
  • Writing good release notes, small mini-blog and share on r/rust and twitter and such

Build system discussions

• Or really: how do you use Rust GPU?

• Right now done in build.rs that builds the compiler and the shader crate through spirv-builder

• Has a bunch of problems:

  • The core library is difficult to use
  • 2 spriv crates built at the same time locks it up, not great
  • possible:
    • custom sysroot
    • custom rust backend

• @repi: impossible to solve all 3 build phases in cargo today

• Examples of other ways of building

  • Rust: x.py
  • cargo make ("cross-platform" bash scripts in a toml)
  • Ark bark-like (Rust program instead of shell/python script that builds everything)

• Also want to run tests and check links.

Other

• @Jake-Shadle: Move spirv-tools to separate repo?
  • Decision: yes let's move it to simplify things in this repo