The runtime

Core

42 symbols, imported from @driftengine/core.

Explained in The loop.

Classes

BrowserStore: localStorage, with every access guarded.
LoadTracker: What an app is waiting on, as one weighted number.
MemoryStore: Volatile store: the test double, and the fallback when nothing persists.
MessageQueue
OnceSet: A persisted set of one-time flags: tutorial prompts, first-run hints, "you have seen this" markers.
PreferenceStore: A live preference record: the loaded value, validated updates, persistence and change notification for whatever applies them to running systems.
RemoteSaveStore
StepBudget
TickTrace

FrameSource: A source of animation frames. window satisfies it, and so does an XRSession.
KeyValueStore: Where persisted state goes.
LoadSummary
LoadTask: One thing being waited for.
LoopHooks: Fixed-timestep game loop with render interpolation.
LoopOptions
MessageQueueOptions
PreferenceSchema: Persisted player preferences: a validated record in a KeyValueStore.
QueuedMessage: One transient message at a time, in priority order.
RemoteSaveOptions
SavableRandom: A generator whose position can be read and written.
SaveBackend: The asynchronous side, which the consumer implements.
SaveTimer: The delay, taken as a capability rather than reached for.
StepBudgetOptions: Spending a slice of a frame on work that can stop, without spending more than the slice.
TickTraceLike: What a fixed-step simulation produced, tick by tick.
TimeCurve
TimeCurveOptions

curveOffsetSec: Source seconds elapsed by localSec into the curve.
curveSpanSec: Source seconds a whole segment consumes — durationSec for every kind, and worth asking for rather than assuming: a caller composing segments needs the answer the curve actually gives, not the one it promises.
defaultSaveTimer: The global timer where there is one, and a timer that never fires where there is not.
defaultStore: The default store: the browser's when it works, memory when it does not.
hashToUnit: A single well-mixed value in [0, 1) from one integer seed.
linearCurve: A curve that does nothing, for a segment that is played straight.
loadPreferences
mulberry32
pickBySeed: Deterministically choose one item from a list.
savableMulberry32
savePreferences
startLoop: Starts the loop immediately. Returns a stop function.
timeCurve: Build a curve, validating at construction.

SaveStatus: What the queue is doing, for an indicator a player can read.
TimeCurveKind: Re-timing a stretch of playback: how much source time one second of clip time is worth.