A fork of bevy to implement some features for forestia
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Ian Kettlewell b35974010b
Get Bevy building for WebAssembly with multithreading (#12205)
# Objective

This gets Bevy building on Wasm when the `atomics` flag is enabled. This
does not yet multithread Bevy itself, but it allows Bevy users to use a
crate like `wasm_thread` to spawn their own threads and manually
parallelize work. This is a first step towards resolving #4078 . Also
fixes #9304.

This provides a foothold so that Bevy contributors can begin to think
about multithreaded Wasm's constraints and Bevy can work towards changes
to get the engine itself multithreaded.

Some flags need to be set on the Rust compiler when compiling for Wasm
multithreading. Here's what my build script looks like, with the correct
flags set, to test out Bevy examples on web:

```bash
set -e
RUSTFLAGS='-C target-feature=+atomics,+bulk-memory,+mutable-globals' \
     cargo build --example breakout --target wasm32-unknown-unknown -Z build-std=std,panic_abort --release
 wasm-bindgen --out-name wasm_example \
   --out-dir examples/wasm/target \
   --target web target/wasm32-unknown-unknown/release/examples/breakout.wasm
 devserver --header Cross-Origin-Opener-Policy='same-origin' --header Cross-Origin-Embedder-Policy='require-corp' --path examples/wasm
```

A few notes:

1. `cpal` crashes immediately when the `atomics` flag is set. That is
patched in https://github.com/RustAudio/cpal/pull/837, but not yet in
the latest crates.io release.

That can be temporarily worked around by patching Cpal like so:
```toml
[patch.crates-io]
cpal = { git = "https://github.com/RustAudio/cpal" }
```

2. When testing out `wasm_thread` you need to enable the `es_modules`
feature.

## Solution

The largest obstacle to compiling Bevy with `atomics` on web is that
`wgpu` types are _not_ Send and Sync. Longer term Bevy will need an
approach to handle that, but in the near term Bevy is already configured
to be single-threaded on web.

Therefor it is enough to wrap `wgpu` types in a
`send_wrapper::SendWrapper` that _is_ Send / Sync, but panics if
accessed off the `wgpu` thread.

---

## Changelog

- `wgpu` types that are not `Send` are wrapped in
`send_wrapper::SendWrapper` on Wasm + 'atomics'
- CommandBuffers are not generated in parallel on Wasm + 'atomics'

## Questions
- Bevy should probably add CI checks to make sure this doesn't regress.
Should that go in this PR or a separate PR? **Edit:** Added checks to
build Wasm with atomics

---------

Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: daxpedda <daxpedda@gmail.com>
Co-authored-by: François <francois.mockers@vleue.com>
2024-03-25 19:10:18 +00:00
.cargo Add nightly hint to config.toml (#12257) 2024-03-02 14:41:37 +00:00
.github Get Bevy building for WebAssembly with multithreading (#12205) 2024-03-25 19:10:18 +00:00
assets Meshlet rendering (initial feature) (#10164) 2024-03-25 19:08:27 +00:00
benches Move commands module into bevy::ecs::world (#12234) 2024-03-02 23:13:45 +00:00
crates Get Bevy building for WebAssembly with multithreading (#12205) 2024-03-25 19:10:18 +00:00
docs Meshlet rendering (initial feature) (#10164) 2024-03-25 19:08:27 +00:00
docs-template Update wgpu to v0.19.3 and unpin web-sys. (#12247) 2024-03-02 00:44:51 +00:00
errors Make feature(doc_auto_cfg) work (#12642) 2024-03-23 02:22:52 +00:00
examples Meshlet rendering (initial feature) (#10164) 2024-03-25 19:08:27 +00:00
src Make feature(doc_auto_cfg) work (#12642) 2024-03-23 02:22:52 +00:00
tests Migrate from LegacyColor to bevy_color::Color (#12163) 2024-02-29 19:35:12 +00:00
tools Make feature(doc_auto_cfg) work (#12642) 2024-03-23 02:22:52 +00:00
.gitattributes Enforce linux-style line endings for .rs and .toml (#3197) 2021-11-26 21:05:35 +00:00
.gitignore Ignore screenshots generated by screenshot example (#11797) 2024-02-09 20:13:28 +00:00
Cargo.toml Meshlet rendering (initial feature) (#10164) 2024-03-25 19:08:27 +00:00
CHANGELOG.md 0.13 changelog (#11918) 2024-02-17 07:22:02 +00:00
clippy.toml Use clippy::doc_markdown more. (#10286) 2023-10-27 22:49:02 +00:00
CODE_OF_CONDUCT.md Update CODE_OF_CONDUCT.md 2020-08-19 20:25:58 +01:00
CONTRIBUTING.md Add typos - Source code spell checker (#12036) 2024-02-26 16:19:40 +00:00
CREDITS.md UI Texture 9 slice (#11600) 2024-02-07 20:07:53 +00:00
deny.toml Fix duplicate dependencies on raw-window-handle (#12309) 2024-03-05 08:24:37 +00:00
LICENSE-APACHE Let the project page support GitHub's new ability to display open source licenses (#4966) 2022-06-08 17:55:57 +00:00
LICENSE-MIT Let the project page support GitHub's new ability to display open source licenses (#4966) 2022-06-08 17:55:57 +00:00
README.md Update funding link (#12425) 2024-03-11 21:46:04 +00:00
rustfmt.toml Cargo fmt with unstable features (#1903) 2021-04-21 23:19:34 +00:00
typos.toml remove comment in typos.toml (#12303) 2024-03-04 20:34:22 +00:00

Bevy

License Crates.io Downloads Docs CI Discord

What is Bevy?

Bevy is a refreshingly simple data-driven game engine built in Rust. It is free and open-source forever!

WARNING

Bevy is still in the early stages of development. Important features are missing. Documentation is sparse. A new version of Bevy containing breaking changes to the API is released approximately once every 3 months. We provide migration guides, but we can't guarantee migrations will always be easy. Use only if you are willing to work in this environment.

MSRV: Bevy relies heavily on improvements in the Rust language and compiler. As a result, the Minimum Supported Rust Version (MSRV) is generally close to "the latest stable release" of Rust.

Design Goals

  • Capable: Offer a complete 2D and 3D feature set
  • Simple: Easy for newbies to pick up, but infinitely flexible for power users
  • Data Focused: Data-oriented architecture using the Entity Component System paradigm
  • Modular: Use only what you need. Replace what you don't like
  • Fast: App logic should run quickly, and when possible, in parallel
  • Productive: Changes should compile quickly ... waiting isn't fun

About

  • Features: A quick overview of Bevy's features.
  • News: A development blog that covers our progress, plans and shiny new features.

Docs

Community

Before contributing or participating in discussions with the community, you should familiarize yourself with our Code of Conduct.

  • Discord: Bevy's official discord server.
  • Reddit: Bevy's official subreddit.
  • GitHub Discussions: The best place for questions about Bevy, answered right here!
  • Bevy Assets: A collection of awesome Bevy projects, tools, plugins and learning materials.

Contributing

If you'd like to help build Bevy, check out the Contributor's Guide. For simple problems, feel free to open an issue or PR and tackle it yourself!

For more complex architecture decisions and experimental mad science, please open an RFC (Request For Comments) so we can brainstorm together effectively!

Getting Started

We recommend checking out the Quick Start Guide for a brief introduction.

Follow the Setup guide to ensure your development environment is set up correctly. Once set up, you can quickly try out the examples by cloning this repo and running the following commands:

# Switch to the correct version (latest release, default is main development branch)
git checkout latest
# Runs the "breakout" example
cargo run --example breakout

To draw a window with standard functionality enabled, use:

use bevy::prelude::*;

fn main(){
  App::new()
    .add_plugins(DefaultPlugins)
    .run();
}

Fast Compiles

Bevy can be built just fine using default configuration on stable Rust. However for really fast iterative compiles, you should enable the "fast compiles" setup by following the instructions here.

Bevy Cargo Features

This list outlines the different cargo features supported by Bevy. These allow you to customize the Bevy feature set for your use-case.

Thanks

Bevy is the result of the hard work of many people. A huge thanks to all Bevy contributors, the many open source projects that have come before us, the Rust gamedev ecosystem, and the many libraries we build on.

A huge thanks to Bevy's generous sponsors. Bevy will always be free and open source, but it isn't free to make. Please consider sponsoring our work if you like what we're building.

This project is tested with BrowserStack.

License

Bevy is free, open source and permissively licensed! Except where noted (below and/or in individual files), all code in this repository is dual-licensed under either:

at your option. This means you can select the license you prefer! This dual-licensing approach is the de-facto standard in the Rust ecosystem and there are very good reasons to include both.

Some of the engine's code carries additional copyright notices and license terms due to their external origins. These are generally BSD-like, but exact details vary by crate: If the README of a crate contains a 'License' header (or similar), the additional copyright notices and license terms applicable to that crate will be listed. The above licensing requirement still applies to contributions to those crates, and sections of those crates will carry those license terms. The license field of each crate will also reflect this. For example, bevy_mikktspace has code under the Zlib license (as well as a copyright notice when choosing the MIT license).

The assets included in this repository (for our examples) typically fall under different open licenses. These will not be included in your game (unless copied in by you), and they are not distributed in the published bevy crates. See CREDITS.md for the details of the licenses of those files.

Your contributions

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.