RadarTracker

A live admin map for your Fabric server.

Radar opens a separate desktop window on the machine running your server (or your singleplayer world) showing every online player as a dot on a real-time, top-down render of the world's terrain — built the same way vanilla in-game maps are, so it looks and reads like a Minecraft map, not a debug overlay. Click a player's dot (or their name in the list) to jump your configured "viewer" character into spectator mode right on top of them.

It's built for server admins, moderators and SMP hosts who want a fast, always-on overview of where everyone is — without alt-tabbing into a third-party web map or asking players to share coordinates.

✨ Key Features

• Live top-down map for the Overworld, the Nether and the End, each rendered from real block data as players explore — no pre-generated tiles, no external web server.
• Correct Nether rendering. Unlike a naive "highest block" scan (which just finds the solid bedrock roof everywhere), Radar tunnels through the Nether's ceiling to render the actual cave surface underneath, so the Nether map looks like a map instead of a flat grey slab.
• Player markers with name labels, updated on a configurable interval.
• Click-to-spectate. Clicking a player teleports your chosen "viewer" player into spectator mode at their location — great for quickly checking in on someone without a chat command.
• Per-player info panel: health, hunger, game mode, ping, current biome, distance from world spawn, full inventory and worn armor, and resource-pack acceptance status.
• Dark and light themes, plus a fully customizable accent color via a standard color picker (any RGB color, not a fixed palette).
• Built-in localization — Russian, English and Ukrainian out of the box (language: ru / en / uk in the config).
• Tunable performance. Update interval, chunks scanned per server tick, and scan radius around each player are all configurable, so you can trade map freshness for server tick time on larger player counts.
• Zero client-side footprint. Radar only needs to be installed on the server (see Requirements below) — players don't need the mod, and it changes nothing about their game client.

⚠️ Requirements & Important Compatibility Note

• Minecraft: 1.21.11
• Mod Loader: Fabric Loader >=0.19.5
• Java: 21+
• Required dependency: Fabric API

This is a server-side desktop tool, not an in-game GUI. Radar's map window is a native Java/Swing window that pops up on whatever machine the server process is running on — it is not rendered inside Minecraft and is not visible to connecting players. That means:

• It works great for singleplayer (the integrated server counts as "the server"), LAN worlds, and self-hosted servers running on a desktop/PC with a display attached.
• It will not open on a typical headless dedicated server (most rented Minecraft hosting has no display attached). Radar detects this automatically (GraphicsEnvironment.isHeadless()) and simply skips opening the window with a warning in the log, instead of crashing — but the map itself will not be available in that environment.

If you're hosting on a standard rented game panel without desktop/VNC access, this mod currently isn't for you — check back if remote-map support gets added in a future version.

🔧 Configuration

On first launch, Radar creates config/radar.json next to your other server configs:

Key	Default	What it does
viewerName	""	Player name that gets teleported into spectator mode when you click a marker
updateIntervalTicks	10	How often (in ticks; 20 = 1 second) player positions and the map refresh
chunksPerTick	4	How many map chunks get (re)rendered per server tick
chunkScanRadius	6	Radius (in chunks) around each player that gets scanned for the map
language	ru	UI language: ru, en, or uk
theme	dark	UI theme: dark or light
accentColor	0xFFC107	Accent color (player markers, selection highlight) as 0xRRGGBB

You can also set the accent color from inside the app via a standard color picker — no need to hand-edit hex values.

🗺️ How It Works

Radar hooks into the server tick loop to sample map colors and player data without touching the game's own state off the main thread — all UI reads go through immutable snapshots, so there's no risk of corrupting world/entity state from the Swing thread. Terrain color sampling follows vanilla's own map-coloring rules (MapColor) for a familiar look, with a custom ceiling-piercing scan for dimensions like the Nether that don't have an open sky.

🌐 Localization

Radar ships with Russian, English and Ukrainian translations built in. Switch languages any time by editing language in the radar window.

📜 License:

All Rights Reserved.

This mod's source code and compiled distributions may not be copied,
modified, redistributed, or used in derivative works without the
explicit written permission of the author.

🙏 Credits:

Created by CarymeDer.

P.S. If you have any questions, just leave a comment — I'll be happy to answer!