The overlap crosshair sat on the pair's area centroid. For a split,
holed or concave overlap, that point can be off the red material:
between two patches, in a hole, or inside a curve.
PlateOverlapPair.Marker is a point inside the pair's largest island.
It is the island's pole of inaccessibility (PolyLabel), searched to a
tenth of the island's area/perimeter within a 4096-cell budget. If
that bounded search does not land inside (a long thin sliver), the
marker falls back to the midpoint of the widest interior run of a
horizontal scan line placed between vertex heights.
The overlay crosshair, marker hit testing, hover coordinates
("Marker:") and the cutting-inspection ring now use the marker.
Centroid stays the true area centroid. View > Overlap Check > Display
> Centroids is now labelled Markers.
Before the marker existed, its call sites used the centroid. Two
patches, a covered frame, a half annulus and a thin crescent then put
it off the material; now all four land on it. Disabling the scan-line
fallback fails its test. On the 389-plate corpus, markers add about
0.4 ms per overlapping pair; pair and area results are unchanged.
The material-overlap diagnostic clipped every triangle of one part
against every triangle of the other, then carved each fragment by
every hole triangle. Curved overlaps produced thousands of fragments,
and a part sitting inside another part's cutout was slow even when
clear.
PlateOverlapAnalyzer now intersects each candidate pair's hole-aware
material once with Clipper2, in part-local coordinates on a 1e-8 grid.
Each operand is its outline minus the union of its holes (positive
fill rule). Regions become connected islands: a counterclockwise
outline plus clockwise Holes, including an island that both parts'
holes enclose together. PolygonAreaMoments.TrySubtract gives each
island's net moments. A pair is reported when its total shared area
exceeds Tolerance.Epsilon. Out-of-range or nonfinite coordinates make
the pair incomplete rather than clear. The overlay and the cutting
inspection highlight fill outlines with their holes.
On 389 real PEP-converted plates the pair, clamp-finding and issue
sets are identical to the previous kernel. Pair areas are equal or up
to 0.0002 larger: the kernel drops fragments below its area threshold.
With material prepared, the per-plate clipping maximum fell from
2.6 s to 52 ms (total 5.0 s to 0.5 s).
Engine and validation checks still use Collision.
1b422ef read absolute-mode hole subprograms by converting an
incremental-mode copy of every clean program. Rebuilding absolute
endpoints from incremental deltas is not exact: after a rapid at
1e12 a 1x10 rectangle moved by about 2.4e-5 and a real 2e-5 overlap
was reported clear, in the overlap overlay and pre-post verification
as well as Plan Cutting.
Convert programs directly again, which reads absolute coordinates
exactly, and refuse an absolute-mode subprogram as an incomplete
check instead: the converter adds a call's frame offset to
incremental moves only, so it would read such a hole at its frame
origin. OpenNest writes hole subprograms in incremental mode. The
null-list and unknown-instruction refusals from 1b422ef stay, and
CopyForGeometry is private to the planner again.
PlateOverlapAnalyzer converted clean programs directly with
ConvertProgram.ToGeometry, which adds call offsets only to
incremental moves, so holes in absolute-mode subprograms were read at
their frame origin. A square with two absolute holes reported
"Native material contours cross or touch", and the Plan Cutting
overlap gate blocked it while the incremental twin passed. Convert an
owned incremental-mode copy instead (PreparedContours.CopyForGeometry,
now internal, the same normalization the cutting planner uses).
The analyzer also threw on a program whose Codes list was null and
cast or cloned instructions it does not know. It now refuses a
missing list and anything other than the exact built-in instruction
types as an incomplete check, before any copy or conversion runs.
Pre-post verification and the plate overlap overlay share this path.
aj