showScreenCalibration()

Display an interactive screen-size calibration step. The participant uses an on-screen reference (e.g. a credit card) to measure their physical screen dimensions. The result is stored internally and used during tracker calibration.

const result = await chiasm.showScreenCalibration();
// result → { screenWidthCm: 34.5, screenHeightCm: 19.4 }

Returns an object with screenWidthCm and screenHeightCm.

note

Call this before setupTrackerWithRetries — the tracker requires screen dimensions to calibrate correctly.