The Clipper validator flagged valid Opus55 and PEP layouts (P260805-03,
P260626-03). Two causes:
- Arc.ToPoints(circumscribe) scales every vertex out by 1/cos(step/2),
endpoints included, so a 0.03125 corner fillet flattened at 0.01 poked
0.013 past the straight edges it meets. ClipperBridge now flattens itself:
circumscribed arcs keep their endpoints on the arc and put interior
vertices on tangent intersections, with the segment count chosen so the
outward error stays within the tolerance. Arc.ToPoints is unchanged for
its other callers.
- The conservative padding made a layout exactly at the spacing fail.
NestValidator now uses OffsetForValidation: the same conservative
flattening, round joins at a tenth of the tolerance, no padding. Its only
leniency is that join chord error at convex corners.
With both, Opus55 is valid on all 26 benchmark jobs (25 before the
Clipper migration; the old failure was a spike artifact).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Its callers now take Clipper region offsets, which never produce the
self-intersections it patched over (and it only caught proper crossings,
so spikes survived it anyway). Polygon.OffsetEntity was its last caller;
the override is required by Entity but has no callers, so it becomes a
Clipper miter offset that keeps the Left/Right semantics and the input
winding. FindCrossing, SplitAtCrossing, SegmentsIntersect and the static
CalculateArea helper go with it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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>
Offsetting entity by entity leaves spikes and inverted loops wherever a
feature is narrower than the spacing, and RemoveSelfIntersections only
catches proper crossings. ClipperBridge flattens a ShapeProfile into one
region (perimeter positive, cutouts negative) and inflates it in a single
Clipper pass with round joins, so narrow features collapse and holes that
close up disappear.
Conservative mode circumscribes perimeter arcs, inscribes cutout arcs and
pads the inflation by the chord tolerance, so the result never
under-estimates the spacing. It replaces the circumscribed-polygon
guarantee the BestFit/PartBoundary callers rely on.
Clipper stays confined to CPU preparation whose output is cached; the
per-pair Collision path remains hand-rolled for GPU portability.
LayoutPart's display offset now goes through the bridge.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ajandClaude Opus 5.5