@web-engine-dev/scheduler

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@web-engine-dev/scheduler / defineSystem

Function: defineSystem()

defineSystem<TContext>(id, fn): SystemBuilder<TContext>

Creates a system builder for fluent system definition.

Provides a chainable API for configuring system metadata including stage, dependencies, labels, parallelization, and run conditions.

Type Parameters

TContext

TContext = unknown

Parameters

id

SystemId

System identifier (string or Symbol)

fn

SystemFn<TContext>

System function to execute

Returns

SystemBuilder<TContext>

A SystemBuilder instance

Example

// Basic usage
const movement = defineSystem('movement', (ctx) => {
  for (const entity of ctx.world.query(Position, Velocity)) {
    entity.get(Position).x += entity.get(Velocity).x * ctx.deltaTime;
  }
})
  .inStage(CoreStages.UPDATE)
  .after('input')
  .build();

// Full example with all options
const physics = defineSystem<GameContext>('physics', updatePhysics)
  .inStage(CoreStages.UPDATE)
  .after('input')
  .before('render')
  .label('physics', 'simulation')
  .parallel()
  .runIf((ctx) => !ctx.isPaused)
  .build();