Prefabs

Reusable MAST labels that encapsulate spawn logic for entities.

Overview

A prefab is any MAST label invoked via prefab_spawn or prefab_extends. The prefab label receives START_X, START_Y, START_Z, NAME, and any additional keys from the caller's data dict as task variables, then runs its own spawn and setup logic.

Prefabs are the recommended way to define reusable entity templates — NPC ships, stations, grid objects, or any complex multi-step spawn sequence — that can be instantiated many times with different parameters.

See the prefab procedural API for the full function reference.

Declaring a prefab label

Any label can act as a prefab. By convention, prefab labels are named with a prefab_ prefix:

== prefab_enemy_fighter ==
~~ id = spawn_npc("fighter", "tsc", START_X, 0, START_Z, NAME) ~~
~~ add_role(id, "enemy") ~~
~~ brain_add(id, patrol_label) ~~

Spawning a prefab

~~ prefab_spawn(prefab_enemy_fighter, {"START_X": 5000, "START_Z": 3000, "NAME": "Fighter #"}) ~~

The # in NAME is automatically replaced with an incrementing number: "Fighter 01", "Fighter 02", etc.

Spawning multiple prefabs in parallel

await task_all(
    prefab_spawn(prefab_enemy_fighter, {"START_X": 1000, "START_Z": 1000, "NAME": "Alpha #"}),
    prefab_spawn(prefab_enemy_fighter, {"START_X": 2000, "START_Z": 1000, "NAME": "Beta #"}),
    prefab_spawn(prefab_enemy_fighter, {"START_X": 3000, "START_Z": 1000, "NAME": "Gamma #"}),
)

Extending a prefab

prefab_extends runs the label as a sub-task of the calling task rather than as an independent task:

== my_label ==
~~ prefab_extends(setup_subsection, data={"tier": 2}) ~~