Runtime
app
Small application facade over a runtime.
App exists for the outermost host layer: browser bootstraps, tests, game
loops, engine adapters, or demos that want a familiar bootstrap(...) /
update(...) entrypoint without introducing a second ownership layer for
the ECS world.
In this library the runtime is still the real owner of world state,
services, events, lifecycle buffers, and schedule execution. App only
gives that runtime an application-shaped shell so integration code can stay
simple while ECS semantics remain explicit.
Reach for this module when the host should think in terms of "initialize the
game once, then advance one frame at a time", but you still want schedules
and runtime boundaries to stay visible in the implementation.
Examples
// Build the runtime first. `App` wraps it, but does not replace it.
const runtime = Game.Runtime.make({
schema: Game,
services: Game.Runtime.services(
Game.Runtime.service(RenderClock, { now: () => performance.now() })
)
})
// Expose a host-friendly shape to the outer game loop.
const app = App.makeApp(runtime)
// Run setup schedules once before the frame loop starts.
app.bootstrap(setupSchedule)
// Advance one explicit ECS frame from the host loop.
const frame = () => {
app.update(updateSchedule)
requestAnimationFrame(frame)
}
requestAnimationFrame(frame)
Creates an application facade on top of an existing runtime.
Use this at the integration boundary when you want a stable "app" object
for a browser host, test harness, or engine adapter, but you do not want to
hide the fact that schedules still drive everything underneath.
bootstrap(...) remains a direct alias of runtime.initialize(...), and
update(...) remains a direct alias of runtime.tick(...). The wrapper is
ergonomic, not semantic.
// Construct the ECS runtime with the services the systems declared.
const runtime = Game.Runtime.make({
schema: Game,
services: Game.Runtime.services(
Game.Runtime.service(RenderClock, { now: () => performance.now() })
)
})
// Wrap it once so the outer host deals with a tiny app-shaped contract.
const app = App.makeApp(runtime)
// Bootstrap setup schedules before starting the steady update loop.
app.bootstrap(setupSchedule)
// Drive one schedule per host frame or test step.
app.update(updateSchedule)