Altar Prototyper

Based on game build 714014 | Last updated: 2026-03-04

Overview

altar_prototyper.lua defines two prefabs—ancient_altar (intact) and ancient_altar_broken (damaged)—which function as high-tier prototyping tables in DST. These prefabs integrate multiple components to provide research capabilities (prototyper), crafting feedback (workable), durability and repair (repairable), dynamic lighting, and randomized creature spawning on interaction or destruction. It also integrates with the ruins respawn system to support world-generation-based resurrection mechanics.

The intact version uses a high-tier tech tree (TUNING.PROTOTYPER_TREES.ANCIENTALTAR_HIGH) and supports full prototyping; the broken version uses a lower-tier tree (TUNING.PROTOTYPER_TREES.ANCIENTALTAR_LOW) and can be repaired to full integrity to revert to the intact variant.

Usage example

-- Create an intact ancient altar
local altar = SpawnPrefab("ancient_altar")
altar.Transform:SetPosition(pos:Get())
altar.Transform:SetScale(1.5, 1.5, 1.5)

-- Access its prototyper component for research tree
local tree = altar.components.prototyper.trees

-- Manually trigger crafting (typically done via action handler)
altar.components.prototyper:onactivate()

-- Repair a broken altar (assuming a player `player` has thulecite)
local broken_altar = SpawnPrefab("ancient_altar_broken")
broken_altar.components.repairable:DoRepair(player, "thulecite")

Dependencies & tags

Components used:

• prototyper (for research tree and onactivate/onturnon/onturnoff hooks)
• workable (for hammering/repair progress)
• repairable (only on ancient_altar_broken)
• lootdropper (only on ancient_altar_broken)
• inspectable (on both prefabs, via common_fn)

Tags added:

• altar, structure, stone, ancient_station, prototyper (added in common_fn)

Properties

Property	Type	Default Value	Description
_lightframe	net_smallbyte	0 (client-simulated frame counter)	Tracks animation frame for light intensity interpolation; synced via "lightdirty" event.
_islighton	net_bool	false	Boolean flag indicating whether the altar’s light is on; controls radius and sound state.
_lightmaxframe	number	MAX_LIGHT_OFF_FRAME (30)	Maximum frame count for the current light state transition.
_activecount	number	0	Counts active crafting sessions; ensures sound and animation persist while in use.
scrapbook_specialinfo	string	"CRAFTINGSTATION"	Metadata for scrapbook categorization (only on intact altar).

Main functions

complete_onactivate(inst)

• Description: Called when the intact altar is activated (e.g., via crafting). Plays animation, starts looping proximity sound, and lights the altar if off. Increments _activecount and schedules completion sound after 1.5 seconds.
• Parameters: inst (Entity) — the altar entity.
• Returns: Nothing.

complete_onturnon(inst)

• Description: Turns the light on smoothly for the intact altar. Initiates light frame interpolation if needed, sets _islighton to true, and begins looping proximity animation.
• Parameters: inst (Entity).
• Returns: Nothing.

complete_onturnoff(inst)

• Description: Turns the light off smoothly for the intact altar. Resets light frame and sets _islighton to false.
• Parameters: inst (Entity).
• Returns: Nothing.

broken_onactivate(inst)

• Description: Similar to complete_onactivate, but for the broken variant. Plays hit_broken animation and switches to idle_broken loop.
• Parameters: inst (Entity).
• Returns: Nothing.

broken_onrepaired(inst, doer, repair_item)

• Description: Handles repair progress. If incomplete, plays repair sound and animation. When work reaches full (workleft == maxwork), replaces itself with an ancient_altar (intact) prefab and spawns FX.
• Parameters:

• inst (Entity) — the broken altar.
• doer (Entity) — the entity performing repair.
• repair_item (string or nil) — the repair material used (ignored; repair is driven by workable callbacks).

• Returns: Nothing.

DoRandomThing(inst, pos, count, target)

• Description: Triggers random creature or item spawns at a position using weighted probabilities (spawns table) and action parameters (actions table). Supports trinket variants and sanity/health modifiers. Primarily called on hammering or activation.
• Parameters:

• inst (Entity) — the altar instance.
• pos (Vector) — base position for spawns.
• count (number, optional) — number of spawn attempts.
• target (Entity, optional) — player to assign as combat target for spawned creatures.

• Returns: Nothing.

Events & listeners

• Listens to:

  • "lightdirty" (client-side only) — triggers OnLightDirty, which initiates light frame interpolation for local light animation.
  • "ms_sendlightningstrike" — pushed during spawn/repair/hammer events to trigger visual FX.

• Pushes:

  • "onprefabswaped" — fired when ancient_altar_broken repairs to full or is hammered into ancient_altar_broken, carrying {newobj = prefab}.
  • "entity_droploot" — indirectly via LootDropper:DropLoot() (see connected lootdropper.lua).