InputLog

class InputLog

import { InputLog } from '@driftengine/network';

Constructor

`new`

constructor(options: InputLogOptions)

Parameter	Type	Description
`options`	`InputLogOptions`

Properties

Name	Type	Description
`participants`readonly	`number`
`depth`readonly	`number`
`inputBytes`readonly	`number`

Accessors

Name	Type	Description
`windowStart`get	`number`	The oldest tick this log holds. Everything below it has been dropped.
`windowEnd`get	`number`	One past the newest tick this log will accept.

Methods

`holds`

holds(tick: number): boolean

Whether a tick is inside the window at all.

Parameter	Type	Description
`tick`	`number`

`retain`

retain(oldest: number): void

Move the window so oldest is the earliest tick kept, forgetting what falls off.

Parameter	Type	Description
`oldest`	`number`

The slots that leave are cleared rather than left, because their slotTick would otherwise match a tick a whole window later and answer a stale input as a confirmed one.

`set`

set(participant: number, tick: number, payload: Uint8Array): boolean

Record a real input. true when this changed what the slot held, which is what tells a rewind whether it has anything to do. false also means refused, for a tick outside the window — see holds to tell the two apart when it matters.

Parameter	Type	Description
`participant`	`number`
`tick`	`number`
`payload`	`Uint8Array`

A confirmed input matching the guess is the common case on a held control, and replaying for it would burn a rewind to produce the identical world.

`into`

into(participant: number, tick: number, out: Uint8Array): boolean

The input to simulate with, guessing and storing one if none has arrived.

Parameter	Type	Description
`participant`	`number`
`tick`	`number`
`out`	`Uint8Array`

false means it was guessed, or that the tick is outside the window, in which case out is zeroed. A caller deciding whether a tick can be confirmed reads that; a caller simulating does not care, because either way out holds the bytes this tick ran with, now and on every replay.

`isConfirmed`

isConfirmed(participant: number, tick: number): boolean

Whether a real input for this participant and tick has arrived.

Parameter	Type	Description
`participant`	`number`
`tick`	`number`

`isComplete`

isComplete(tick: number): boolean

Whether every participant's input for this tick has arrived. What lockstep advances on.

Parameter	Type	Description
`tick`	`number`

`confirmedThrough`

confirmedThrough(upTo: number): number

The highest tick at or below upTo such that every tick from the window's start up to it is complete, or -1.

Parameter	Type	Description
`upTo`	`number`

Walked upward from the start of the window and stopped at the first gap, which is the property that matters: ticks 40 and 42 confirmed with 41 missing is not a session confirmed to 42, and answering 42 would let a peer discard the snapshot it still needs to correct 41.