LOD Server Support

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. It can even show far terrain on servers running Distant Horizons.

Try it live: join lod-server-support.bitvox.me with Voxy and this mod installed. Supports Minecraft 26.3, 26.2, 26.1, 1.21.11, 1.21.10, and 1.21.1.

Demo Video

Compatibility

Clients use the Fabric mod on every version; on 26.3, 26.2, 26.1, and 1.21.1 a NeoForge client works as well. Supported servers:

NeoForge support is best-effort, with far player rendering available on 1.21.1 only.

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 and JourneyMap based on the LOD data. This is on by default in new installs; toggle "Map Ingestion" in the client Sodium settings, click Apply, then reconnect. Xaero's cave maps fill too, including the Nether at any height. Servers can ask clients not to add LOD terrain to their maps with privacy.request_no_map_ingestion (clients older than 0.19.0 then get no LODs). Players with the lss.map_ingestion permission are exempt.

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 (unless privacy.request_no_map_ingestion is turned on), and clients can update without breaking compatibility with older servers.

On NeoForge (1.21.1) use Roxy to load the Fabric Voxy jar. Tested working with Roxy 0.2.0, Voxy 0.2.16-beta (the 1.21.11 build), Sodium 0.8.12, and Forgified Fabric API 0.116.15. If distant Voxy chunks do not show up, turn off environmental fog in your video settings.

Distant Horizons servers (experimental, on by default). Join a server running Distant Horizons 3.3.x and the far terrain loads in through Voxy, even without LOD Server Support on the server. For the best results we still recommend installing LOD Server Support on the server too, it always takes priority when present. Works with Fabric clients on every version and NeoForge clients on 26.2, 26.1, and 1.21.1. Don't install the Distant Horizons client mod alongside it. Turn it off with "Allow DH Server Terrain" in the client Sodium settings (NeoForge: restart the game). Not endorsed by the Distant Horizons team.

Installation

Install LOD Server Support on both the server (LOD Server Support Fabric mod or NeoForge mod) and every client that wants these features. Without LOD Server Support on both the connecting client and on the server it will not function (except on Distant Horizons servers, see above). Clients without LOD Server Support can still join normally.

Configuration

Config files are generated during first run at config/lss-server-config.yaml on Fabric and NeoForge. Client settings are in config/lss-client-config.yaml. Settings are grouped by feature and documented inline, including units and restart/reconnect requirements.

Edit the YAML and run /lsslod reload on the server or /lss reload on the client.

Commands

Server (Fabric and NeoForge)

• /lsslod stats - Show per-player transfer statistics
• /lsslod diag - Show detailed diagnostics (config, bandwidth, queue depths)
• /lsslod reload - Reload server settings from YAML; settings that still need a restart are reported
• /lsslod store status - Show LOD store status (state, hit/miss counters, size)
• /lsslod store backfill start|stop|status - Control the background pre-warm walk
• /lsslod help - List all commands

Client (Fabric and NeoForge)

• /lss reload - Reload client settings from YAML; settings that still need a reconnect are reported
• /lss clearcache - Clear the local column cache, forcing all chunks to be re-requested from the server
• /lss reset - Wipe this world'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)

Server Performance Tuning

Turn the LOD store on. Set enabled: true under storage.lod_store (requires a restart). It caches the preprocessed LOD data to disk for CPU savings, with the drawback of extra disk usage that can be comparable to the size of your world files.

On Fabric and NeoForge, 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 setting enabled: false under storage.lod_store.backfill.

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:

• network.bandwidth.per_player_mib_per_second / network.bandwidth.global_mib_per_second bound the chunk serve rate. They count uncompressed bytes on purpose so compression doesn't quietly raise the real ceiling. Actual network utilization depends on compression and the terrain.
• generation.concurrency.global / generation.concurrency.per_player 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. Setting enabled: false under generation stops new generation; existing jobs finish.
• storage.disk.max_concurrent_reads 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.

Pre-generate the world. Obviously the best thing you can do for player experience is avoid chunk generation by pre-generating your map with a tool such as Chunky.

Redistribution

This mod is MIT-licensed, redistribution with attribution is welcome, and usage by modpacks is allowed.