Function createSystem

createSystem<T extends BaseEntity>(
components: (keyof T)[],
update: (entity: T, deltaTime: number) => void,
): SystemFn<T>

Creates a simple system function from a query and update function.

Helper for creating systems that iterate over entities with specific components. Reduces boilerplate for common system patterns.

Type Parameters

T extends BaseEntity

Parameters

components: (keyof T)[]
Component keys to query for.
update: (entity: T, deltaTime: number) => void
Function to call for each matching entity.

Returns SystemFn<T>

A SystemFn that can be registered with the scheduler.

Example

// Movement system using createSystem helper
const movementSystem = createSystem(
  ['position', 'velocity'],
  (entity, dt) => {
    entity.position.x += entity.velocity.x * dt;
    entity.position.y += entity.velocity.y * dt;
    entity.position.z += entity.velocity.z * dt;
  }
);

scheduler.register({
  name: 'movement',
  fn: movementSystem,
  priority: 10
});

Example

// Health decay system
const decaySystem = createSystem(['health'], (entity, dt) => {
  entity.health -= 1 * dt;
  if (entity.health <= 0) {
    // Mark for removal
    entity.dead = true;
  }
});