Components, Resources & Queries

Working with Components

• List built-ins: const all = ecs.components(); // map of aliases → ComponentType
• Resolve one: const Transform = ecs.component("Transform"); // aliases are case-insensitive, with/without Component
• Create an instance: const t = ecs.createComponent(Transform);

Custom Components

// ID must match /[a-z0-9_-]/
const Poison = ecs.registerComponent("poison");
// Optional supplier lets you return a custom Java object
const Custom = ecs.registerComponent("custom", () => new MyComponent());

• Without a supplier, SimpleScripting uses a dynamic map-backed component (JsDynamicComponent) with get/set methods.
• Custom components are fully serializable; pair them with codecs on the Java side if you need schema control.

Archetypes & Spawning

• Build a queryable archetype: const movers = ecs.archetype([Transform, Velocity]);
• Spawn entities with any component list:

const ref = ecs.spawn(worldRef, [t, v], "SPAWN");

Resources

Register global data that hangs off the registry, not specific entities:

const Cache = ecs.registerResource("my_cache", () => new MyCache());

Resources persist through IResourceStorage when configured on the Java side.

Building Queries

You can pass either arrays of component types or prebuilt Query objects into system options:

• ecs.queryAll([Transform, Velocity])
• ecs.queryNot([Sleeping])
• ecs.queryOr([TeamA], [TeamB])
• ecs.queryAny() // wildcard
• ecs.archetype([Transform, Velocity]) // acts as a Query

Reuse queries

Create queries once at module scope and reuse them across systems to avoid allocations inside ticks.

Data Conversions

Vector-like inputs accept {x,y,z}, arrays [x,y,z], or a single number (applied to all axes). This applies to helpers like setPosition, addForce, and component setters.

Next: wire those components into systems and listen to ECS events.