launch!

packages/steam/launch.nix

@@ -1,20 +1,57 @@
-{pkgs, ...}: {
+{pkgs, ...}: let
+  mangoConfigList = ["cpu_temp" "gpu_temp" "ram" "vram"];
+  mangoConfigStr = builtins.concatStringsSep "," mangoConfigList;
+
+  gamescopeArgsList = [
+    "--adaptive-sync"
+    "--hdr-enabled"
+    "--mangoapp"
+    "--rt"
+    "--steam"
+  ];
+  gamescopeArgsStr = builtins.concatStringsSep " " gamescopeArgsList;
+
+  steamArgsList = [
+    "-pipewire-dmabuf"
+    "-tenfoot"
+  ];
+  steamArgsStr = builtins.concatStringsSep " " steamArgsList;
+
+  myGamescopeSteamScript = pkgs.writeShellApplication {
+    name = "start-gamescope-steam";
+    runtimeInputs = [
+      pkgs.gamescope
+      pkgs.steam
+      pkgs.mangohud
+    ];
+    text = ''
+      #!/usr/bin/env bash
+      set -xeuo pipefail
+
+      export MANGOHUD=1
+      export MANGOHUD_CONFIG="${mangoConfigStr}"
+
+      exec ${pkgs.gamescope}/bin/gamescope ${gamescopeArgsStr} -- ${pkgs.steam}/bin/steam ${steamArgsStr}
+    '';
+  };
+in {
   programs = {
     gamescope = {
       enable = true;
       capSysNice = true;
     };
     steam = {
-      remotePlay.openFirewall = true; # Open ports in the firewall for Steam Remote Play
-      dedicatedServer.openFirewall = true; # Open ports in the firewall for Source Dedicated Server
-      localNetworkGameTransfers.openFirewall = true; # Open ports in the firewall for Steam Local Network Game Transfers     enable = true;
+      enable = true;
+      remotePlay.openFirewall = true;
+      dedicatedServer.openFirewall = true;
+      localNetworkGameTransfers.openFirewall = true;
       gamescopeSession.enable = true;
     };
   };
+
   hardware.xone.enable = true;
-  environment = {
-    loginShellInit = ''
-      [[ "$(tty)" = "/dev/tty1" ]] && ~/.config/nixos/gs.sh
-    '';
-  };
+
+  environment.loginShellInit = ''
+    [[ "$(tty)" = "/dev/tty1" ]] && ${myGamescopeSteamScript}/bin/start-gamescope-steam
+  '';
 }