RpImmersion

RpImmersion is a server and client-side companion mod for RpEssentials, designed for immersive Roleplay servers running Minecraft 1.21.1 on NeoForge. It gives server administrators fine-grained control over the atmosphere experienced by players — fog, camera effects, weather immersion, and a fully custom RP calendar — all configurable in real-time without restarts.

Current version: 0.0.2

Please note that the fog provided by the mod isn't functional with shaders because of technical limitation that I can't handle!

Requirements

Dependency Version Side Required Minecraft 1.21.1 Both ✅ NeoForge 21.1.219+ Both ✅ RpEssentials 4.1.7+ Both ✅ ImmersiveMessages neoforge-1.21.1:1.0.18 Client ⬜ Optional TxniLib neoforge-1.21.1-1.0.24 Client ⬜ Optional

ImmersiveMessages and TxniLib are only required on the client if you use weatherMessageMode = IMMERSIVE or scheduleDeathHoursNotifyMode = IMMERSIVE. The server runs fine without them, and clients without them will gracefully fall back to action bar display.

Features

Fog System

Server-controlled fog fully replaces vanilla fog for players when active. Everything is configured in rpimmersion-fog.toml.

• Named presets — define fog colors (RGB), start/end distances, and fade transition duration. Apply them anywhere.
• Circular zones — assign a preset to a zone defined by center coordinates and radius. Higher-priority zones win when overlapping.
• Biome-based fog — automatically apply a preset when a player enters a specific biome. Wildcard support (minecraft:*, *:dark_*).
• RpEssentials zone overrides — piggyback on zones already defined in RpEssentials's named zone system. No need to redefine coordinates.
• Day/Night variants — every zone, biome, and global preset supports separate dayPreset and nightPreset. Transitions are animated.
• Global fog — a fallback preset applied to all players when no zone or biome matches.
• World border fog — a dedicated high-priority preset activates automatically when a player steps outside the world border. Useful for dramatic boundary effects.
• Per-player override — staff can instantly set a specific fog for one player via command, overriding all other rules.
• Smooth transitions — all fog changes ease in and out with a configurable duration. No abrupt jumps.
• Optimized sync — the server only sends a packet when the fog state actually changes for a player (checked every N ticks, configurable). No network spam.

Weather Immersion

Enhances Minecraft's weather system with atmosphere and control. Configured in rpimmersion-weather.toml.

• Weather fog integration — CLEAR, RAIN, and THUNDER each map to a fog preset. Applied as a low-priority fallback when no zone or biome fog is active, creating a natural weather atmosphere.
• Lightning frequency control — multiply or reduce the rate of lightning strikes during thunderstorms. Extra bolts are placed randomly near online players within a configurable radius.
• Camera shake on lightning — when lightning strikes, nearby players feel a camera shake proportional to their distance from the bolt. Close strike = strong shake, distant strike = subtle shake. The effect uses a smooth decay envelope.
• Mainstream mod compatibility — shake is applied additively to camera angles (not a replacement), so it stacks cleanly with Sodium, Embeddium, Optifine, Oculus, and any other mod that touches the camera. Never causes conflicts.
• Client shake override — the server can allow clients to reduce or disable camera shake via their own client config (Options → Mods). The server can also lock it, enforcing the configured intensity for all players.
• Automatic weather cycle — define a sequence of weather steps (CLEAR → RAIN → THUNDER → CLEAR…) with durations in real-time minutes. The server cycles through them automatically.
• Narrative messages — when weather changes, a configurable message is broadcast to all players. Supports CHAT, ACTION_BAR, and IMMERSIVE (with ImmersiveMessages) display modes.

RP Calendar

A fully persistent, server-driven roleplay calendar. Configured in rpimmersion-calendar.toml.

• Completely custom structure — define your own month names, number of months, days per month (uniform or per-month), and optionally day-of-week names.
• Configurable time ratio — control how fast RP time passes relative to real server time. ticksPerRpMinute × rpMinutesPerHour × rpHoursPerDay gives you full control.
• Persistent — the current date and pause state are saved in world/data/rpimmersion/calendar.json. The calendar survives server restarts.
• Pauseable — staff can freeze the calendar in place. The date is still displayed (with a configurable pause indicator), but time stops accumulating.
• Flexible display — show the date as a HUD overlay, in the action bar, both, or nowhere. The format string accepts any combination of {day}, {dayName}, {month}, {monthName}, {year}, {hour}, {minute} placeholders.
• Live commands — set the date to any value, advance it by N minutes, pause/resume, or force a sync to all players — all without restarting.

Commands

All commands require staff permission (as defined by RpEssentials).

Fog

Command Description /rpimmersion fog set global <preset|clear> Apply a fog preset to all players, or clear the global override. /rpimmersion fog set player <player> <preset|clear> Apply a fog preset to one player specifically. /rpimmersion fog clear global Remove the global fog override. /rpimmersion fog clear player <player> Remove the per-player fog override. /rpimmersion fog list List all loaded fog presets with their parameters. /rpimmersion fog status Display the current fog state (global override, world border, zone and biome counts). /rpimmersion fog reload Reload fog config from disk and re-sync all players.

Weather

Command Description /rpimmersion weather set <CLEAR|RAIN|THUNDER> Force a specific weather state on the server. /rpimmersion weather status Show the current weather and active fog preset. /rpimmersion weather reload Reload weather config from disk.

Calendar

Command Description /rpimmersion calendar status Display the current RP date, time, and pause state. /rpimmersion calendar pause <true|false> Pause or resume the calendar. /rpimmersion calendar set <year> <month> <day> [hour] [minute] Set the calendar to a specific date and time. /rpimmersion calendar advance <minutes> Advance (or rewind if negative) the calendar by N RP minutes. /rpimmersion calendar reload Force a sync of the current date to all connected players.

Configuration

Three server-side config files are generated automatically under config/rpimmersion/ on first launch. One client-side config is generated in the standard NeoForge client config location.

File Contents rpimmersion-fog.toml Presets, zones, biomes, RpEssentials overrides, world border fog, day/night settings, optimization rpimmersion-weather.toml Weather fog mapping, lightning frequency & shake, auto cycle, narrative messages rpimmersion-calendar.toml Month/day structure, time ratio, start date, display format rpimmersion-client.toml Client-side shake intensity override, fog disable toggle

All server configs support live reload via /rpimmersion fog reload, /rpimmersion weather reload, and /rpimmersion calendar reload. No server restart required.

Fog Preset Format

# name;red;green;blue;start;end;transitionSeconds presets = [ "night_fog;0.05;0.05;0.1;5.0;30.0;3.0", "morning_mist;0.7;0.75;0.8;2.0;20.0;5.0", "border_void;0.0;0.0;0.0;1.0;8.0;2.0" ]

Fog Zone Format

# zoneName;centerX;centerZ;radius;preset;priority[;dayPreset;nightPreset] zones = [ "dark_woods;100;-200;80;cursed_forest;10;morning_mist;night_fog" ]

Weather Fog Format

# weatherType;fogPreset weatherFogPresets = [ "RAIN;morning_mist", "THUNDER;purge" ]

Calendar Structure Example

monthNames = ["Janvier", "Février", "Mars", "Avril", "Mai", "Juin", "Juillet", "Août", "Septembre", "Octobre", "Novembre", "Décembre"] daysPerMonth = [30] # A single value applies to all months dayNames = ["Lundi", "Mardi", "Mercredi", "Jeudi", "Vendredi", "Samedi", "Dimanche"] dateFormat = "§7{dayName} {day} {monthName}, An {year} — {hour}h{minute}"

Data Storage

File Contents world/data/rpimmersion/calendar.json Current RP date and pause state

Technical Notes

• Fog transitions use a fixed start/target interpolation model. The "from" value is captured at the moment a new fog is set, ensuring a clean linear ease-in/out regardless of how many transitions overlap.
• Camera shake adds delta values to the existing camera angles rather than replacing them, making it additive and fully compatible with Sodium, Embeddium, Optifine, Oculus, and any other rendering mod.
• No continuous packet spam — fog state is recalculated every N ticks (configurable, default 3 seconds) per player, and a packet is only sent if the resolved state differs from what was last sent.
• RpEssentials integration uses Java reflection at runtime to read named zones, so the dependency is declared as required in the mod metadata but never hard-linked at compile time beyond isStaff().