bevy/docs/linux_dependencies.md
Thomas Heartman e317058677 Docs/more nixos instructions (#2775)
# Objective

Expand the documentation for NixOS setups (as discussed in Discord)

## Solution

Added more info to `linux_dependencies.md` about NixOS. This is based off my own experience (as documented in [this blog post](https://blog.thomasheartman.com/posts/bevy-getting-started-on-nixos)), so I can't confirm that it'll work for everyone. However, if there are further tweaks necessary, then I think that this should nevertheless work as a good starting point and should give future users an idea of what they may need to change or update.

Feedback and tweaks are very welcome 😄
2021-09-06 19:16:09 +00:00

148 lines
4.5 KiB
Markdown

# Installing Linux dependencies
This page lists the required dependencies to build a Bevy project on your Linux machine.
If you don't see your distro present in the list, feel free to add the instructions in this document.
## Ubuntu 20.04
```bash
sudo apt-get install g++ pkg-config libx11-dev libasound2-dev libudev-dev
```
Depending on your graphics card, you may have to install one of the following:
`vulkan-radeon`, `vulkan-intel`, or `mesa-vulkan-drivers`
Compiling with clang is also possible - replace the `g++` package with `clang`.
### Windows Subsystem for Linux (WSL 2)
Graphics and audio need to be configured for them to work with WSL 2 backend.
Please see the ubuntu [WSL documentation](https://wiki.ubuntu.com/WSL) on how to set up graphics and audio.
## Fedora
```bash
sudo dnf install gcc-c++ libX11-devel alsa-lib-devel systemd-devel
```
If there are errors with linking during the build process such as:
```bash
= note: /usr/bin/ld: skipping incompatible /usr/lib/libasound.so when searching for -lasound
/usr/bin/ld: skipping incompatible /usr/lib/libasound.so when searching for -lasound
/usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-redhat-linux/10/../../../libasound.so when searching for -lasound
/usr/bin/ld: skipping incompatible /lib/libasound.so when searching for -lasound
/usr/bin/ld: skipping incompatible /usr/lib/libasound.so when searching for -lasound
/usr/bin/ld: cannot find -lasound
```
Add your arch to the end of the package to remove the linker error. For example:
```bash
sudo dnf install alsa-lib-devel.x86_64
```
## Arch / Manjaro
```bash
sudo pacman -S libx11 pkgconf alsa-lib
```
## Void
```bash
sudo xbps-install -S pkgconf alsa-lib-devel libX11-devel eudev-libudev-devel
```
## NixOS
Add a `build.rs` file to your project containing:
```rust
# build.rs
fn main() {
if cfg!(target_os = "linux") {
println!("cargo:rustc-link-lib=vulkan");
}
}
```
These packages provide the dependencies required to run a bevy project. They can be installed globally or via nix-shell.
Based on your global configuration it also might be necessary to allow unfree packages:
```bash
export NIXPKGS_ALLOW_UNFREE=1 # needed for lutris
nix-shell -p cargo pkgconfig udev lutris alsaLib x11 xorg.libXcursor xorg.libXrandr xorg.libXi vulkan-tools vulkan-headers vulkan-loader vulkan-validation-layers
```
Alternatively, you can define `shell.nix` containing:
```nix
# shell.nix
{ pkgs ? import <nixpkgs> { } }:
with pkgs;
mkShell {
buildInputs = [
cargo
pkgconfig udev alsaLib lutris
x11 xorg.libXcursor xorg.libXrandr xorg.libXi
vulkan-tools vulkan-headers vulkan-loader vulkan-validation-layers
];
}
```
And enter it by just running `nix-shell`.
You should be able compile bevy programms using `cargo` within this nix-shell.
### Fast compilation
According to the Bevy getting started guide (for v0.5), you can enable fast compilation by add a Cargo config file and by adding `lld` and `clang`. As long as you add `clang` and `lld` to your environment, it should mostly work, but you'll still need to modify the Cargo config file so that it doesn't point to `/usr/bin/clang` anymore.
Working off the above files, let's make the necessary changes.
For `.cargo/config.toml`, change the path to the linker from `/usr/bin/clang` to `clang`:
``` diff
[target.x86_64-unknown-linux-gnu]
- linker = "/usr/bin/clang"
+ linker = "clang"
rustflags = ["-Clink-arg=-fuse-ld=lld", "-Zshare-generics=y"]
```
In `shell.nix`, add `lld` and `clang`:
``` diff
buildInputs = [
cargo
pkgconfig udev alsaLib lutris
x11 xorg.libXcursor xorg.libXrandr xorg.libXi
vulkan-tools vulkan-headers vulkan-loader vulkan-validation-layers
+ clang lld
];
```
### Building apps and using the GPU
If you run into issues with building basic apps or activating the GPU ('thread 'main' panicked at 'Unable to find a GPU!'), then you may need to update your environment's `LD_LIBRARY_PATH`. To solve issues relating to missing `libudev.so.1` files, `alsa` drivers, and being unable to find a GPU, try updating the environment variable in your `shell.nix` by creating a `shellHook`:
``` diff
{ pkgs ? import <nixpkgs> { } }:
with pkgs;
mkShell {
+ shellHook = ''export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${pkgs.lib.makeLibraryPath [
+ pkgs.alsaLib
+ pkgs.udev
+ pkgs.vulkan-loader
+ ]}"'';
buildInputs = [
```
## Opensuse Tumbleweed
```bash
sudo zypper install libudev-devel gcc-c++
```