World Mirror

Ever wanted to take a piece of your favorite multiplayer server offline? World Mirror is a client-side Fabric mod that silently captures the world around you—including terrain, entities, and container contents—and saves it as a fully playable local singleplayer world.

Whether you're backing up a base, archiving a server before a wipe, or saving a minigame map, World Mirror works quietly in the background without lagging your game.

✨ Key Features

• Seamless Background Syncing: Exports chunk data to your disk automatically (default every 10 seconds) on a separate thread, meaning zero game freezes while you play.
• Smart "Dirty-Chunk" Tracking: Only updates chunks that have changed since the last save, keeping exports lightning fast even for massive worlds.
• Comprehensive Capture:
  • Multi-Dimension: Fully supports the Overworld, Nether, End, and any custom dimensions.
  • Containers: Intercepts inventory packets. Just open a chest, barrel, hopper, or furnace while the mod is active, and its contents will be saved to your mirrored world!
  • Block Entities: Persists sign text, banner patterns, player heads, beacon effects, and lectern books.
• In-Game UI: Press I to open a sleek status screen to view sync stats, manage your download state, and handle chunk conflicts.
• Smart World Mapping: Automatically maps server IPs to dedicated local folders. The same server will always export to the same folder, so you never accidentally overwrite the wrong save.
• International Support: Fully translated into English, Simplified Chinese, Traditional Chinese, and Japanese.

🎮 How to Use

1. Join a multiplayer server (or singleplayer world).
2. Press P to start a download session. You'll see an active status in your action bar.
3. Explore! Walk around to load terrain. Remember to open any containers if you want their contents saved.
4. When you're done, press P again to stop, or press O to force an immediate export.
5. Play offline: Your world is saved in <.minecraft>/downloaded_worlds/ by default. (Tip: Change the save location to your Saves Folder in the settings to play your mirrored worlds instantly from the singleplayer menu!)

Need to clear your cache and start fresh? Just press L.

⚙️ Configuration & Conflicts

World Mirror is fully configurable via Mod Menu. Access global settings to change your save location, sync interval, and in-game logging levels.

You can also handle Chunk Conflicts (when a chunk already exists on your local disk) globally or per-world using three strategies:

• Overwrite (Default): The server chunk always replaces your local copy.
• Ignore: Keeps your local copy; only brand new chunks are written.
• Manual: Keeps the local copy but queues the chunk in your I status screen for you to resolve later.

📥 Installation & Requirements

• Minecraft: 1.21.11
• Mod Loader: Fabric (≥ 0.18.2)
• Dependencies:
  • Fabric API
  • LibGUI (≥ 15.1.0) - Required for the status screen
• Optional: Mod Menu (Highly recommended for accessing the settings screen)

Note: Because this is a client-side mod, it can only capture data the server actually sends to you. Container contents will only be saved if you physically open them, and server-side-only data (like complex mob AI paths or command block commands) will revert to defaults.