The tolerance-free rectangle test was fed approximated material: the layout
check passed it the 1e-4-grid validation outline (a strip of real material
that wholly contains a 1e-5 clamp could vanish), and interactive fill and
the overlap check passed 0.001 inscribed arc chords (a clamp inside a disk
but outside its chords read as clear). All three now flatten the native
contours at a quarter of the clamp's smaller side, lines kept exact, so the
arc-chord sliver can never hold the clamp. Ordinary clamps are unchanged.
PM 407f5eb7-329f-41e4-947e-64ad52aa4034
A clamp zone smaller than the validation outline tolerance went through
ClipperBridge.OffsetForValidation, collapsed to a null outline and made
NestLayoutCheck (and Default scoring) throw. The keep-out is now an exact
four-vertex ring, and a keep-out below 0.001 on either axis is judged by a
tolerance-free rectangle test (KeepOutOverlap): positive-area overlap only,
hole-aware, never a silent clear. Tolerances are unchanged.
PM 6859db53-e39b-4135-85c6-4967037cf880
aj