Per-entity offsetting left spikes and inverted loops wherever a feature is
narrower than the spacing (1.nest), and RemoveSelfIntersections only
caught proper crossings. The callers that already flatten to polygons now
take a single Clipper region offset instead:
- PolygonHelper (BestFit) and PartBoundary use the conservative mode, which
keeps their never-under-estimate guarantee. PartBoundary also keeps holes
that appear when a perimeter curls back on itself.
- NestValidator offsets perimeter and cutouts in one region; Clipper drops
collapsed cutouts, so the collapsed-or-flipped heuristic goes away.
- CutOff.IntersectPerimeter offsets through the bridge. The old
OffsetEntity(Left) grew CW perimeters but shrank CCW ones, so with the
plate's perimeter cache a cut-off ran through the part; slots narrower
than twice the clearance now close up instead of leaving a gap.
- GetOffsetPartLines (3 overloads) and the AddOffset* helpers had no
callers and are removed, as is EntityView's never-defined DRAW_OFFSET
block.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>