v7.8 put the cup at an anatomically-fit acetabular centre. v7.9 adds a live safe-zone judgment: as you drag inclination, anteversion, and ΔPT, the viewer evaluates the orientation against the static Lewinnek (1978) and Callanan (2011) zones and against a posture-aware functional band derived from the v7.5 engine coefficients. The badge updates every frame; the underlying anatomy is unchanged.
state: sphere-fit centre, anatomical frame, free orientation knobs.
gap: the user sees a cup at a defensible centre, but the viewer never says whether that orientation is reasonable. The judgement lives in the engine and the docs, not in the picture.
Reviewers asked for the safe-zone overlay (UX-9). v7.9 answers it.
added: live Lewinnek (1978) zone, live Callanan (2011) zone, and a posture-aware functional band.
shown: a per-axis bar for INC and AV with the static zones drawn behind a standing-needle and a sitting-needle, plus three combined badges (Lewinnek, Callanan, Functional sit).
No new dependency, no new mesh. The judgement is geometry on top of the v7.5 engine constants. Surgeon-supervised; safe zones are necessary but not sufficient — see VZ-1.
Click a phenotype to mirror the three SPIN-THA reference cases (STIFF/ADAPT/HYPER) in the live viewer.
Static zones in radiographic INC/AV. Functional band shifts the static target by the v7.5 tilt coefficients × ΔPT, displaying the band a standing radiograph would have to land in for the sitting cup to remain Lewinnek-compliant. Bars are clipped to 0–60° INC and 0–50° AV.
CT-frame mesh transformed by (x,y,z) → (x, z, −y) so anterior faces the viewer in the default camera.