LightMyFire - Coal&Resin

I use AI to review code and assist with optimization and integrity; I manually test and review every mod, and all decisions and code remain my own.

Current release: 1.0.6, audited against the current governed Valheim CLIENT assemblies and Jotunn 2.30.0.

Release status

1.0.4 switches the barrels to the game's own assets: Valheim's barrel with a small heap of the game's own Coal, Resin or Wood on the lid. Barrels already placed in your world keep working and keep their contents.

Earlier fixes still included:

• Restores real nearest-to-next barrel fallthrough when the nearest matching barrel grants only part of a light's missing fuel or has none available.
• Keeps owner-authoritative request/grant/ack/refund networking, persists outstanding reservation state in the barrel ZDO across ownership handoffs, and retains Jotunn patch-level version enforcement.
• Uses only governed /build Valheim CLIENT, BepInEx and Jotunn references for release builds.
• Dedicated/headless servers skip the client-only range marker and fuel marker while preserving the same gameplay/network barrel structure.

LightMyFire adds separate placeable Coal Barrel, Resin Barrel and Wood Barrel pieces to Hammer > Misc.

Each barrel has the same 8x4, 32-slot inventory space as a black metal chest and costs 100 Wood, 40 Iron, and 40 Tar. The Coal Barrel accepts only vanilla Coal, the Resin Barrel only vanilla Resin and the Wood Barrel only regular Wood (not Fine Wood, Core Wood or other woods) - every other item is rejected. Fill one with its matching fuel and any compatible light within range gets topped up automatically on the next scan.

Development note

AI-assisted tools support code analysis, optimization review, implementation refinement, and verification support.

Created and maintained by R4V9N1.

Features

• Built from Valheim's current native barrel/container prefab through Jotunn, preserving its normal network, interaction, collider and WearNTear behaviour.
• Uses only the game's own assets: Valheim's barrel, with a small heap of the game's own Coal, Resin or Wood on the lid so you can tell the barrels apart at a glance. The marker has no collider and cannot steal clicks or damage hits from the barrel.
• Coal-only / Resin-only inventories. Wrong-fuel items (and everything else) are rejected on drop, shift-click, and quick-transfer; anything that slips through by another mod's path is safely ejected next to the barrel, never deleted.
• Tops up, doesn't just refill. Partially-fueled lights are topped up to their own maximum; full lights are left untouched.
• Works with any loaded Fireplace-based light source - vanilla or modded - that burns vanilla Coal or Resin and has finite fuel capacity, with no hardcoded torch/sconce list.
• The Wood Barrel tops up campfires, iron fire pits, bonfires and hearths, plus hot tubs and stone ovens. Press Shift+E on a stone oven to switch its automatic top-up off or on (shown in its hover text; the same for every player). Trader camp fires never run out and are skipped. With InventoryLink installed, building and crafting never take wood from the Wood Barrel.
• The Coal Barrel also tops up smelters and blast furnaces (any smelting station that burns Coal). Lights always come first: smelters are filled about 30 seconds after the lights, once the lights' requests have been answered.
• Nearest-matching-barrel-first selection, falling through to the next-nearest barrel if one barrel can't fully cover a light's missing fuel.
• Transaction-safe multiplayer: fuel is only ever moved by the object's own owner, using request/grant/acknowledge/refund with persisted ZDO reservation metadata and timeouts so barrel ownership handoffs/disconnects recover the same refund ledger instead of losing peer-local state.
• One efficient shared scan, 5 minutes by default, plus a lightweight maintenance tick for transaction cleanup.
• Configurable feeding range (50m default) and scan interval - server-controlled, synced to every client.
• Place Stacks and holding E on a barrel move all of its fuel from your bag, even when the barrel is empty.
• A thin white dotted range ring marks the exact feeding-radius circumference while placing a barrel and while that barrel inventory is open. There is no filled area marker.
• Works in single-player and multiplayer.
• Compatible with Terramizer, TerramizerServer, EquipmentSheet, and InventoryLink 0.2.6 or newer.

Installation

Install LightMyFire and Jotunn on the server and every connecting client. LightMyFire uses patch-level network version matching, so server and clients should run the same LightMyFire version.

Configuration

Config file:

BepInEx/config/r4v9n1.lightmyfire.cfg

Enabled, feeding range, and the refill interval are set by the server/host and synced to clients; a client's local values for those three are overridden. LogTransfers and LogDiagnostics are local-only. Enable LogDiagnostics while troubleshooting to see barrel readiness and scan counts.