FG Greeter

Figthing game greeter - A Linux greeter with a fighting game animation.

The goal is to have a fun greeter where entering your password simulate a fighting game experience. When you press any characters, your fighter will hit the opponent, comboing if you are typing fast enough. If you provided the correct password, you will deliver a finishing blow and enter your session. Otherwise, you will be countered and a new round starts !

To use this greeter, see the installation guide

You can also quickly try it out with a fake greeter with the test-greeter.sh script, that requires to compile the fakegreet package from greetd

Status

The functionnal part of logging in is working, with a clean state machine handling greetd. The state machine sends animations events that are then used to run the animation.

I am no artist, and both the background and my animations are terrible. I'd like to make them way better, and any help is appreciated !

This greeter is currently using bevy, and while it's fine for a quick result, I'd like to migrate away from it. The issue is that Bevy has a tendency to panic, and we can't let a greeter panic when something is wrong. I would like a more robust solution, and since the visual part is super simple anyway (only one object), I'd like to move to a simpler way of rendering / animating the scene.

Contributing

Anyone is welcome to help, for the code or art. Currently, the code is fully working, so the art and animations is the main pain point of this project.

How does it works ?

The models and animations are exported as a single glb file from blender. The greeter will attempt to load named animations:

• "Idle" -> idle animation
• "Hit.*" -> hit animation

all hits animations will be loaded in, and when a hit is launched, a random hit animation clip is picked.

What's missing ?

Currently, there is support for the windup, finisher, and counter. The idea is that when the password is entered, the character enters a windup state while greetd validates the inputs. If the password is correct, the fighter then delivers a final blow, ideally with nice impact frames, allowing to do a transition to black before launching the user session. If the input is wrong, the opponent can counter the windup, and the round restarts.

All animations for the windup / finisher / coeunter are missing, as well as a reset and enter animation.

These are currently not loaded either, but I would be more than happy to do the missing work on the code side !

Install

NixOS

To use this on NixOS, you have to build it from source manually:

{ lib, pkgs }:
let
  fgGreeterSrc = pkgs.fetchFromGitHub {
    owner = "VirgileHenry";
    repo = "fggreeter";
    rev = "<commit>";
    sha256 = "<git sha>";
  };

  # winit/wgpu dlopen these at runtime
  ldLibPath = lib.makeLibraryPath [ pkgs.wayland pkgs.libxkbcommon pkgs.vulkan-loader ];
  ldPrefix = "--prefix LD_LIBRARY_PATH : ${ldLibPath}";
  assetFolder = "--set BEVY_ASSET_ROOT $out/share/fggreeter";
  postFixup = "wrapProgram $out/bin/fggreeter ${ldPrefix} ${assetFolder}";
in
pkgs.rustPlatform.buildRustPackage {
  pname = "fggreeter";
  version = "0.1.0";
  src = fgGreeterSrc;
  cargoHash = "<cargo lock sha>";
  nativeBuildInputs = [
    pkgs.pkg-config
    pkgs.makeWrapper
  ];
  buildInputs = [
    pkgs.wayland
    pkgs.libxkbcommon
    pkgs.udev
    pkgs.alsa-lib
  ];
  meta = {
    description = "Fighting Game Greeter";
  };
  postInstall = ''
    mkdir -p $out/share/fggreeter
    cp -r assets $out/share/fggreeter/
  '';
  postFixup = postFixup;
}

Then, the greeter uses cage to run a single window app at startup:

{ lib, config, pkgs, ... }:
let
  # Custom greeter that is a rust package to be built from source
  fgGreeter = import ./fggreeter.nix { lib = lib; pkgs = pkgs; };

  # WARNING: only use this if you have a custom layout
  layout = "XKB_DEFAULT_LAYOUT=fr";
  greeterEnv = "${pkgs.coreutils}/bin/env ${layout}";
  cage = "${pkgs.cage}/bin/cage -s -m last --";
  # The log file part can be removed, but it's useful to debug the greeter
  greeter = "${fgGreeter}/bin/fggreeter --user eclipse --command start-hyprland --log-file /var/log/fggreeter/fggreeter.log";
in
{
  services.displayManager.gdm.enable = false;
  services.greetd = {
    enable = true;
    settings.default_session = {
      command = lib.concatStringsSep " " [ greeterEnv cage greeter ];
      user = "greeter";
    };
  };
  systemd.tmpfiles.rules = [ "d /var/log/fggreeter 0755 greeter greeter -" ];
}

Since this uses bevy for now, it might take a few minutes to build.

Not NixOS

I'm using NixOS, and I have no clue on how to set up a custom greeter for other distros. Dig it up !

License

The code is licensed under the Apache 2.0 license.