Block each clamp's keep-out into the max-rects free list before any
packing: same split logic as placements, not a used item (no contact
score, no material). The blocked rectangle accounts for the inflated
item model exactly - material keeps the bottom-edge clearance from the
clamp without paying an extra part-spacing tax; degenerate spans
collapse to the zone centerline (conservative, never permissive).
Zero-clamp sheets skip blocking entirely: three fixture layout hashes
(rectangle grid, mixed shapes, multi-sheet overflow), captured from the
unchanged packer at a3f1124, stay bit-identical (C2). With clamps:
placements never intrude, demand lands between two clamps when it fits,
a full-width front rail makes an otherwise feasible job Incomplete, and
a far-away zone leaves the layout hash equal to no-clamps.
Rectangles lane only; Irregular parity is Slice 2.
Moves the two production plug-in engines into OpenNest.Engine under names
that describe the jobs they suit:
- Rectangles: plain and near-rectangular plates, maximal-rectangles box
packing (was the RectanglesNestingEngine plug-in)
- Irregular: irregular profiles, no-fit-polygon frontier packing (was the
Opus55NestingEngine plug-in)
Their tests and the shared engine contract/layout test kit move into
OpenNest.Engine.Tests/NestingEngines.
The registry maps the old plug-in names to the new engines, so saved desktop
selections, scripts and API requests keep working, and a leftover plug-in DLL
under an old name cannot shadow its replacement. Desktop startup passes the
registry's lookup when restoring the saved Auto Nest engine.
aj