working

README.md

@@ -4,27 +4,46 @@ Landtrain extends Towbars to support chained towing.
 
 ## Important
 
-Project Zomboid base `BaseVehicle.addPointConstraint()` force-breaks existing constraints.
-To keep `1 -> 2` while attaching `2 -> 3`, Landtrain includes a Java class override:
+Project Zomboid base `BaseVehicle.addPointConstraint()` force-breaks existing constraints and chain state in MP.
+To keep `1 -> 2` while attaching `2 -> 3` (and preserve movement replication), Landtrain includes a Java class override:
 
-- `zombie/vehicles/BaseVehicle.class`
+- client install: `zombie/vehicles/BaseVehicle.class`
+- dedicated install: `java/zombie/vehicles/BaseVehicle.class`
+- helper class (both): `LandtrainConstraintAuthHelper.class` in the same `zombie/vehicles` folder
 
 This is the same override pattern used by mods like Realistic Car Physics (manual `zombie` folder copy).
 
 ## Apply patch to game
 
-1. Run:
+1. Patch your local client install:
 
 ```powershell
 .\tools\patch-game-basevehicle.ps1
 ```
 
-2. Ensure both mods are enabled:
-   - `hrsys_towbars`
-   - `hrsys_landtrain`
+2. Patch the dedicated server install:
+
+```powershell
+.\tools\patch-game-basevehicle.ps1 -GameRoot "D:\SteamLibrary\steamapps\common\Project Zomboid Dedicated Server"
+```
+
+3. Ensure both mods are enabled:
+   - `\hrsys_towbars`
+   - `\hrsys_landtrain`
+
+## MP requirement
+
+For multiplayer, every connecting client and the dedicated server must run the patched class.
+If only one side is patched, towing links can desync with no explicit Lua error.
 
 ## Restore vanilla class
 
 ```powershell
 .\tools\restore-game-basevehicle.ps1
 ```
+
+To restore dedicated server too:
+
+```powershell
+.\tools\restore-game-basevehicle.ps1 -GameRoot "D:\SteamLibrary\steamapps\common\Project Zomboid Dedicated Server"
+```