Opt-in "Gyro from this device" (DefaultsKey.gyroFromDevice, off by default,
iOS only): while player 1's forwarded controller reports no rotation rate of
its own — no GCMotion, or the gravity-only motion an Xbox pad exposes — this
device's IMU sources pad 0's wire motion instead. The rumble-on-device
mirror's sibling, data flowing the other way: same session-scoped
UserDefaults read, same hardware-gated settings rows, same pad-0 rule.
DeviceGyro wraps CMDeviceMotion at the ~100 Hz CoreMotion ceiling on a
dedicated serial queue (not main — the controller path's main-queue delivery
is a known jitter source), converts with the shared GamepadWire constants,
and rotates each sample from the device's portrait frame into the controller
frame by interface orientation, so a phone clipped landscape yaws when the
player yaws instead of rolling. The remap matrix is derived and pinned by
DeviceGyroRemapTests.
GamepadCapture owns engage/stand-down (reconcile, suspend/resume, stop), and
suppresses pad 0's controller-motion forwarding while the mirror runs — two
writers on one pad's motion state would fight, and the accel-only stream
would stomp the mirror's gyro with zeros.
Also fixes the stale-motion latch from the gyro sweep on the controller
path: flush now parks motion at zero (keeping the last accel, so gravity
doesn't become free-fall), and the mirror's stop sends the same closing
zero. The host holds motion as state and re-emits it — a nonzero angular
velocity left behind read as endless rotation for as long as an overlay
(Control Center pull-down) kept the app inactive.
enricobuehler
1f54b75c5c