The Obokata current model produced only surge/sway/yaw; MATLAB
VesselFastTime.currentObokata (lines 652-658) also applies roll and pitch
moments from the horizontal current force acting at a vertical arm:
roll = -Fy * (frontalHeight - originZ) * cos(roll) * cos(pitch)
pitch = Fx * (lateralHeight - originZ) * cos(roll) * cos(pitch)
Add these (gap item D1, partial), with a parity test. The remaining D1 items
(per-section spatial current-field sampling, submerged-depth area basis, and the
cdz cross-flow yaw augmentation) depend on coordinate conventions that need
validation against MATLAB reference output and are left documented.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
