✅ Verified in-game — deeper pass: re-confirmed both functions; added a Module constants section (trigger state hash 0x7687DF41, emitters fx_EmitFlameOilrigTower/fx_EmitSmokeStack, 12-20s delay) and actionable Notes, cross-linked oilrig/islandfortress; prior Events fix (OnStateChange is an engine hook, only Event.TimerRelative is a real Event.Create) still holds

Fueltank

Module: fueltank.lua

Overview

The Fueltank module manages the visual effects associated with a fuel tank object. Specifically, it handles starting and stopping flame and smoke emitters when certain state changes occur.

Inheritance

• Inherits from: none — base/utility module
• Imports: none

Instance pattern

This is a stateless manager/utility module (no per-instance tables). It does not track any specific state fields.

Functions

OnStateChange(uiGuid, uiNodeHashName, uiStateHashName)

Engine-invoked lifecycle hook (see Events below) called when the object’s world-state node changes. Converts uiStateHashName to a string via Sys.GuidToString and compares against the literal "0x7687DF41". On match, starts the "fx_EmitFlameOilrigTower" emitter via ObjectState.StartEmitter and schedules _StartSmoke after a random Math.randf(12, 20)-second delay using Event.TimerRelative. Any other state hash is ignored (no else branch).

_StartSmoke(uiGuid, uiNodeHashName, fxName)

Helper invoked only via the timer set up in OnStateChange. Stops the emitter named by fxName (the flame effect) and starts a new "fx_EmitSmokeStack" emitter in its place.

Events

• OnStateChange(uiGuid, uiNodeHashName, uiStateHashName) is an engine-invoked callback, not something this file registers with Event.Create — the same naming/signature convention appears across other resident files (e.g. oilrig.lua, islandfortress.lua). No Event.StateChange constant is referenced anywhere in this file.
• Event.TimerRelative — the only real Event.Create call in this file, used to delay _StartSmoke after the flame starts.

Module constants & tunables

• Trigger state hash: "0x7687DF41" — OnStateChange only reacts when the incoming state hash stringifies to this value; every other state is ignored.
• Emitters (looked up via ObjectState.GetStringHash): flame "fx_EmitFlameOilrigTower" (started on the trigger) then "fx_EmitSmokeStack" (swapped in by _StartSmoke). Swap these two strings to re-skin the burn.
• Flame-to-smoke delay: Math.randf(12, 20) seconds (inline literal).

Notes for modders

• The two emitter template strings are the whole mod lever here — change "fx_EmitFlameOilrigTower" / "fx_EmitSmokeStack" to alter the flame/smoke visuals, or the Math.randf(12, 20) range to change how long the flame burns before it becomes a smoke stack.
• OnStateChange is engine-invoked and gated on the exact hash "0x7687DF41"; if you retarget it to a different world-state, change that literal to match the new state’s hash.
• The same OnStateChange(uiGuid, uiNodeHashName, uiStateHashName) emitter-swap convention shows up on oilrig and islandfortress — those are the pages to compare against for the wider destructible-FX pattern.