From 91670f0d28d20dcaecd38d318fe4f0eba34e7f02 Mon Sep 17 00:00:00 2001
From: ediblerope <fredrik@nordhammer.it>
Date: Thu, 7 May 2026 09:47:55 +0100
Subject: [PATCH] dr-server: wrap wine64 in xvfb-run for headless Unity

Unity's Win64 build still creates a 1x1 hidden window via Win32 even
under -batchmode -nographics. Wine needs an X display to honor that;
without one, startup fails with "Failed to create batch mode window:
Success." after Mono initializes and PhysX comes up. xvfb-run -a gives
it a virtual display with no real X server cost.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
---
 services/dr-server.nix | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/services/dr-server.nix b/services/dr-server.nix
index 548e6ac..aa08f6a 100644
--- a/services/dr-server.nix
+++ b/services/dr-server.nix
@@ -40,7 +40,6 @@ in
         WINEARCH = "win64";
         WINEDEBUG = "-all";
         HOME = dataDir;
-        DISPLAY = "";
       };
 
       preStart = ''
@@ -57,7 +56,11 @@ in
         User = "dr-server";
         Group = "dr-server";
         WorkingDirectory = buildDir;
-        ExecStart = "${wine}/bin/wine64 DR_Server.exe -batchmode -nographics -logFile ${logDir}/server.log";
+        # Unity's Win64 build still tries to create a 1x1 hidden window
+        # via Win32 even with -batchmode -nographics, and Wine needs a
+        # real X display for that — fails with "Failed to create batch
+        # mode window: Success." otherwise. xvfb-run gives it one.
+        ExecStart = "${pkgs.xvfb-run}/bin/xvfb-run -a ${wine}/bin/wine64 DR_Server.exe -batchmode -nographics -logFile ${logDir}/server.log";
         Restart = "on-failure";
         RestartSec = "10s";
       };