Function loft

pub fn loft(
    rings: &Rings,
    stations: &[Station],
    closed: bool,
) -> Result<TriMesh, GeomError>

Stitch stations into a closed solid.

closed wraps the last station onto the first, which welds a periodic seam by index rather than by two samplings agreeing numerically. Open lofts are capped with the profile triangulation at each end.

All stations must share the profile’s ring structure: the walls pair vertices by position, so a differing ring length has no meaningful pairing and is refused rather than silently truncated.