CuttingHoleOrder proposes the cut order of a part's remaining holes as
an OPEN path arrival -> every hole centre exactly once -> the fixed
perimeter entry, reusing CuttingPartOrder's bounded nearest-neighbour +
2-opt/Or-opt machinery (no exhaustive permutations, no new routing
invention). A proposal only: the search still certifies every rapid and
emitted lead; nothing is installed into the search yet.
CuttingPartOrder gains an optional endpoint: the terminal edge joins
EVERY improvement delta (2-opt tail edge on both sides; OrOpt gap to the
open end measures the endpoint distance), so heuristics see route moves
that re-point the path at the entry rather than only final scoring. No
endpoint keeps whole-part semantics byte-identical (control test);
precedence, prerequisites and tie policy unchanged.
Tests: empty/one hole; asymmetric fixture where the endpoint changes the
ORDER (open route ends at C, entry-facing route ends at B) with each
route asserted equal to its brute-force optimum computed from
coordinates; permutation integrity excluding the perimeter; random 7-set
within 1.05x brute force; deterministic tie order; cancellation; legacy
no-endpoint equality. Mutants dropping the terminal edge from OrOpt or
TwoOpt deltas are killed.
Free-order planning was one depth-first search over parts, contours and
entries. A dead end at one part backtracked through every entry
combination of the part before it (about 1,450 for a square with two
holes) before trying another part order, so a 4 x 4 grid of such parts
ran out of its 20000 expansions (and 200000) although cutting it row by
row is safe.
The whole-part order is now an open travelling-salesman path over part
centres from the start point: nearest neighbour, then 2-opt reversals
and Or-opt moves of one to three parts, never placing a part before a
cutoff or nested-part prerequisite. The existing search then plans
contour order and entries along that order. If a part cannot be
reached without crossing parts already cut, the search learns "cut it
before those", backs up to just before the earliest of them, keeps the
parts cut before that point and re-plans the rest from the tool
position there. An attempt stops backtracking after 8 x entries x
contours expansions without getting further, so it learns instead of
retrying the entries of every earlier part. When nothing new can be
learned the result is a refusal, as before. A preserved order is
planned exactly as before.
16- and 36-part grids, in row order and shuffled, are now ready within
the default budget (they were NoSolutionWithinBudget); a 144-part grid
plans in about half a second.