[feature request] source $(nixGL shell) support

[samuela]

It would be super handy to be able to "install" nixGL into a shell session such that I don't have to worry about wrapping each command in nixGL foo ....

Would maintainers be supportive of including such a feature?

[jim3692]

You can alias nix-shell to nixGL nixVulkanIntel nix-shell

[samuela]

That's certainly an option, but what I'm ideally looking for is a solution to "install" nixGL in the currently running shell instead of spawning a new one.

[jim3692]

That's certainly an option, but what I'm ideally looking for is a solution to "install" nixGL in the currently running shell instead of spawning a new one.

Lately Arch updated its gcc version and now that alias fails with these errors:

nix-shell: /nix/store/bn7pnigb0f8874m6riiw6dngsmdyic1g-gcc-13.3.0-lib/lib/libstdc++.so.6: version `CXXABI_1.3.15' not found (required by /usr/lib/libnixexpr.so)
nix-shell: /nix/store/bn7pnigb0f8874m6riiw6dngsmdyic1g-gcc-13.3.0-lib/lib/libstdc++.so.6: version `CXXABI_1.3.15' not found (required by /usr/lib/libnixmain.so)
nix-shell: /nix/store/bn7pnigb0f8874m6riiw6dngsmdyic1g-gcc-13.3.0-lib/lib/libstdc++.so.6: version `CXXABI_1.3.15' not found (required by /usr/lib/libnixstore.so)
nix-shell: /nix/store/bn7pnigb0f8874m6riiw6dngsmdyic1g-gcc-13.3.0-lib/lib/libstdc++.so.6: version `CXXABI_1.3.15' not found (required by /usr/lib/libnixutil.so)

So, I came up with a more "install" solution:

if [[ ! "$IN_NIX_SHELL" = "" ]] && [[ "$IN_NIXGL" = "" ]]; then
  export IN_NIXGL=1
  source <(
    diff <(env) <(nixGL nixVulkanIntel env) \
      | grep '>' | sed 's/^>/export/g'
  )
fi

It extracts the environment variables that nixGL and nixVulkanIntel set, and adds them to the current shell.

[jim3692]

2. Determines which arch are they, and appropiately symlinks each store to /run/opengl-driver(-32)

I can't understand how the games manage to find the OpenGL drivers in that path. Are you exporting the /run/opengl-driver path?

[jim3692]

Great. I will check it. Is there any related documentation to that? I want to understand whether something like this is possible for Vulkan.

[jim3692]

Sorry. My fault. I expected Vulkan to require a different method, as it's exposed with nixVulkanIntel, and not nixGL. Your script seems to work fine on Arch.

[soupglasses]

There's now also https://github.com/soupglasses/nix-system-graphics which is an alternative approach to do this with, which utilizes the /run/opengl-driver approach instead of environment variable magic as nixGL does.

[jim3692]

I started using home-manager. I don't plan to move to system-manager at the moment, so I did the following:

• Created /etc/tmpfiles.d/99-nix-ogl.conf with the following contents. Make sure to replace the {USERNAME}.

  L+ /run/opengl-driver-32 - - - - /nix/var/nix/profiles/per-user/{USERNAME}/profile/drivers/opengl-driver-32
  L+ /run/opengl-driver - - - - /nix/var/nix/profiles/per-user/{USERNAME}/profile/drivers/opengl-driver
  

• Added nixgl to the flake inputs and extraSpecialArgs:

  {
    inputs = {
      # ...
  
      nixgl = {
        url = "github:nix-community/nixGL";
        inputs.nixpkgs.follows = "nixpkgs";
      };
    };
  
    outputs = { home-manager, nixgl, ... }: {
      homeConfigurations."{USERNAME}" = home-manager.lib.homeManagerConfiguration {
        # ...
        extraSpecialArgs = { inherit nixgl; };
      };
    };
  }

• Added the following configuration to home-manager:

  home.packages = [
    nixgl.packages.${pkgs.system}.nixGLIntel
    nixgl.packages.${pkgs.system}.nixVulkanIntel
  
    (
      let
        driversEnv = with pkgs; buildEnv {
          name = "graphics-drivers";
          paths = [ mesa.drivers rocmPackages.clr.icd ];
        };
  
        driversEnv32 = with pkgs; buildEnv {
          name = "graphics-drivers-32bit";
          paths = with pkgsi686Linux; [ mesa.drivers ];
        };
      in pkgs.runCommand "graphics-drivers" {} ''
        mkdir -p $out/drivers ; cd $out/drivers
        ln -s "${toString driversEnv32}" opengl-driver-32
        ln -s "${toString driversEnv}" opengl-driver
      ''
    )
  ]

Now, I can update the Mesa/ROCm drivers for Nix using home-manager, without requiring root privileges.

It's inspired by the way NixOS installs OpenGL/Vulkan/OpenCL drivers.
For more info:
64-bit drivers
32-bit drivers
tmpfiles