LOD Server Support

Enables players with Voxy to see fully rendered terrain out to hundreds of chunks on multiplayer servers without needing to explore the world first. Also includes far player rendering so you can also see other players far beyond the vanilla render distance.

Try it live: join lod-server-support.modrinth.gg with Voxy and this mod installed. Supports Minecraft 26.2, 26.1, 1.21.11, and 1.21.1.

Compatibility

Clients use the Fabric mod on every version; on 1.21.1 a NeoForge client works as well. Supported servers:

Minecraft	Fabric	Paper / Purpur	Folia	NeoForge
26.2	✅	✅	✅ (experimental)	-
26.1	✅	✅	✅ (experimental)	-
1.21.11	✅	✅	✅ (experimental)	-
1.21.1	✅	✅	-	✅

Compatible with AntiXray, Moonrise, C2ME, ViaVersion/ViaBackwards, and most other mods including Create. Can be run alongside Distant Horizons on the same server to support DH clients and Voxy clients simultaneously.

Can populate Xaero's World/Mini Map based on the LOD data, enable in client settings.

LOD Server Support is backwards and forwards compatible from v0.4.0 through the current version. Server operators can freely update to take advantage of improvements without breaking clients on older versions, and clients can update without breaking compatibility with older servers.

On NeoForge (1.21.1) there are two tested client paths, depending on your Sodium version:

• Sodium 0.6.13: the community Voxy NeoForge port with Forgified Fabric API in place of Fabric API. Tested working with Forgified Fabric API 0.116.15 and Voxy NeoForge port 0.2.9-alpha.
• Sodium 0.8.12 (required by current Create Aeronautics / Sable packs): the Fabric Voxy 1.21.1 branch for Sodium 0.8.12 (0.2.15-beta, built from source) loaded through Sinytra Connector with Forgified Fabric API. Tested working inside a large Create pack with Connector 2.0.0-beta.14, Forgified Fabric API 0.116.15, and Sodium 0.8.12-beta.1.

Voxy Server Side is the same mod. Voxy Server Side clients are compatible with LOD Server Support servers and vice versa.

Installation

Install LOD Server Support on both the server (LOD Server Support Fabric mod, Paper plugin, or NeoForge mod on 1.21.1) and every client (LOD Server Support Fabric or NeoForge mod + Voxy). Without LOD Server Support on both the connecting client and on the server it will not function.

Commands

Server (Fabric, NeoForge, and Paper)

• /lsslod stats - Show per-player transfer statistics
• /lsslod diag - Show detailed diagnostics (config, bandwidth, queue depths)
• /lsslod set <setting> <value> - Change common settings live, no restart needed
• /lsslod store status - Show LOD store status (state, hit/miss counters, size)
• /lsslod store backfill start|stop|status - Control the background pre-warm walk (not on Paper)
• /lsslod help - List all commands

Client (Fabric only)

• /lss clearcache - Clear the local column cache, forcing all chunks to be re-requested from the server
• /lss reset - Wipe this worlds's LODs (local cache and Voxy's stored data) and re-stream them fresh
• /lss diag - Show client-side diagnostics (connection, throughput, scan progress, request budget)

Configuration

Config files are generated during first run at config/lss-server-config.json on Fabric and NeoForge or plugins/LodServerSupport/lss-server-config.json on Paper.

Setting	Default	Description
enabled	true	Enable LOD distribution
lodDistanceChunks	512	Max LOD distance in chunks
mbPerSecondLimitPerPlayer	25.0	Per-player bandwidth cap in MiB/s (decimals like 12.5 work), counted before compression
mbPerSecondLimitGlobal	75.0	Total bandwidth cap across all players in MiB/s, counted before compression
enableChunkGeneration	true	Generate missing chunks on demand, so players see terrain nobody has visited
generationConcurrencyLimitGlobal	40	Max chunks generating server-wide at once
generationConcurrencyLimitPerPlayer	40	Max concurrently generating chunks per player
maxConcurrentDiskReads	0	Max LOD disk reads running at once. 0 = auto (half the reader threads while the LOD store is on, all of them otherwise). See Server Performance Tuning
dirtyBroadcastIntervalSeconds	10	Interval for pushing dirty column notifications to clients. 0 disables the pushes entirely
farPlayers	"on"	Show distant players as player models in the LOD terrain. "opt-in" shows only players who opted in, "off" disables. A per-player exclude list, a hide permission, and vanish plugins are honored
farPlayersMaxDistanceBlocks	2048	Max distance in blocks at which far players are visible
lodYieldsToVanillaTransport	true	Pause LOD sending to a player while their connection is backed up, so vanilla packets always go first
enablePingBackstop	true	Cut a player's LOD rate when their ping spikes, keeping gameplay responsive on slow connections
enableSendPacing	true	Smooth LOD sending into small per-tick slices instead of bursts
lodStore	"on" (new installs)	Keeps a compressed copy of every served LOD column in <world>/lss-lod/ and serves repeat requests from it, which is far less CPU and disk work per chunk. The cost: it roughly doubles your world folder. Generated as "on" for brand-new servers; on an upgraded server whose config file doesn't have the key, it stays "off" until you enable it. See Server Performance Tuning
lodStoreBackfill	true	Pre-warms the store with a low-priority background walk of your existing world, so the first player to arrive already gets fast serves. Inert unless lodStore is on. Yields to players, pauses under load, resumes across restarts. Not available on Paper
lodStoreMaxMB	0	Size cap for the store. 0 = uncapped; set a value to bound it, and the oldest columns are evicted first
enableV16Compat	true	Serve legacy v0.4.x-v0.6.x clients through a built-in translation layer. false requires every client to match the server's protocol
enableV18Compat	true	Serve v0.7.x-v0.8.x clients natively, minus only the features their client predates. false drops them to the enableV16Compat fallback
enableV19Compat	true	Serve v0.9.x clients natively. false drops them to the enableV16Compat fallback
xrayObfuscation	"auto"	Anti-xray masking for LOD data. "auto" mirrors your anti-xray engine's own hidden-block list and height cutoff whenever one is detected (Paper's built-in, per world; the DrexHD AntiXray mod on Fabric). "on" forces masking, "off" disables it, in which case LOD data carries real ore locations even on anti-xray servers
xrayHiddenBlocks / xrayMaxBlockHeight	ore list / 64	Fallback list and Y cutoff, used only when no engine settings can be adopted

Server Performance Tuning

Turn the LOD store on. "lodStore": "on" is the single biggest CPU performance win available, it caches the preprocessed LOD data to disk with the drawback of roughly doubling (+70%) the size of your world directory.

When the LOD store is enabled a backfill task will populate it. Maximum CPU savings are only achieved after the store is populated. Check the progress of the task with /lsslod store backfill status. If your world is much larger than the area players commonly visit you can save on disk space by disabling the backfill task with the "lodStoreBackfill": false config.

Use the bandwidth and generation limiters to limit CPU. LOD Server Support's CPU cost is essentially how many columns per second it serves plus how many chunks it generates, and these configs cap exactly that:

• mbPerSecondLimitPerPlayer / mbPerSecondLimitGlobal bound the chunk serve rate. They count uncompressed bytes on purpose so compression doesn't quietly raise the real ceiling. The actual max network utilization will be approximately 1/8th of these limits.
• generationConcurrencyLimitGlobal / generationConcurrencyLimitPerPlayer bound new chunk generation, by far the most expensive thing LOD Server Support can trigger. On a server exploring fresh terrain this dominates, and lowering it is the single biggest saving. enableChunkGeneration: false removes it entirely.
• maxConcurrentDiskReads bounds how many LOD disk reads run at once, so LOD traffic can't monopolize disk I/O that vanilla chunk loading needs. The 0 auto default is right for most servers; lower it to 1 or 2 if gameplay chunk loading stutters while LODs stream, raise it if LOD loading feels slow on fast NVMe storage.

Disable LOD store resweep on Paper. "lodStoreResweepSeconds": 0 This will reduce CPU utilization at a slight cost to correctness, on Paper its possible to miss chunk updates so old LODs could be served.

Redistribution

This mod is MIT-licensed, redistribution with attribution is welcome, and modpacks can reference the official Modrinth project directly. Per Modrinth's reupload policy: XANTHA via Voxy Server Side has the copyright holder's explicit permission to distribute this mod, and derivatives of it, on Modrinth.