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Interface: Telemetry

Defined in: telemetry.ts:257

The running answer to "is this telemetry real?". A property that is present but never varies across a session of deliberate tilting is a stub, and the span is the only thing that can tell you so. This is the number the Lab exists to put in front of a human on day one.

Properties

altitude

altitude: Range

Defined in: telemetry.ts:265


azimuth

azimuth: Range

Defined in: telemetry.ts:266


coalesced

coalesced: number

Defined in: telemetry.ts:262


coalescingRatio

coalescingRatio: number

Defined in: telemetry.ts:295

Samples per pointer event. 1.0 means the browser is not coalescing — we are seeing one sample per event, and the pen's real high-frequency signal (an Apple Pencil samples far faster than the display refreshes) is being thrown away before it reaches us.


events

events: number

Defined in: telemetry.ts:261

pointermove events, as distinct from the samples coalesced inside them.


firstT

firstT: number

Defined in: telemetry.ts:298


intervals

intervals: readonly number[]

Defined in: telemetry.ts:297

The recent inter-sample intervals the median is taken over (idle gaps excluded).


lastT

lastT: number

Defined in: telemetry.ts:299


medianIntervalMs

medianIntervalMs: number

Defined in: telemetry.ts:282

The median interval between consecutive samples, ms — the honest sample rate, and the reason this is not simply samples / elapsed.

A session-span average is a trap, and it caught us: it divides by all the time the pen was in the AIR — between strokes, while you looked at the panel, while you thought about what to draw next. Draw for a second, pause for two, draw for a second, and a 120Hz pen reports 40Hz. The bug is invisible because the number it produces is plausible.

So: intervals are collected per sample, gaps longer than IDLE_GAP_MS are discarded as "the pen was not down", and the median (not the mean — one hitch on a garbage-collection pause would drag a mean) is what gets reported.


minIntervalMs

minIntervalMs: number

Defined in: telemetry.ts:284

The shortest interval ever seen, ms — what the pen can do at its best.


peakRateHz

peakRateHz: number

Defined in: telemetry.ts:288

Peak rate, Hz, from the shortest interval.


predicted

predicted: number

Defined in: telemetry.ts:263


pressure

pressure: Range

Defined in: telemetry.ts:264


rateHz

rateHz: number

Defined in: telemetry.ts:286

Median rate, Hz. The number to trust. 0 until two samples land.


samples

samples: number

Defined in: telemetry.ts:259


support

support: PenSupport | undefined

Defined in: telemetry.ts:258


twist

twist: Range

Defined in: telemetry.ts:267