floor-planner/benchmarks

Optimiser measurements

Run npm run benchmark for Minimise cuts, or npm run benchmark -- --random for Maximise randomness. Both are compared with the original stock-first optimiser's frozen results in baseline.json. The 84 inputs in cases.ts cover rectangular remainders, fireplaces in both directions, room-order permutations, tight and exact stagger limits, fractional stock, large floors, and both supplied angled rooms. --output=/tmp/results.json saves a run; --compare=/tmp/results.json compares against a previous iteration. Do not overwrite the baseline to hide regressions.

Fixed metrics

• Saw passes: crosscuts actually required by the allocation, long-edge rips, and additional shaping edges. Skirting includes bevel and coping operations.
• Cut difficulty: shaping passes, then rip passes, used to break equal saw-count ties. This is an explicit proxy, not an estimate of minutes or tool-specific effort.
• Random appearance: the existing repetition penalty, evaluated independently from the output rows. It penalises nearby repeating joints, similar consecutive steps and staircases, including steps that wrap across a board length. Raw repeat, similar-step and staircase counts are also reported. A lower score is better.
• Waste: purchased stock minus installed material, including kerf. The report gives board counts and waste percentages weighted by purchased stock.
• Validity and runtime: errors, elapsed time, p95 and maximum case time. Tests separately verify coverage, non-overlapping row bands, minimum sizes, stagger, factory ends, rounded stock consumption, cut accounting, references and input purity.

Minimise cuts orders (passes, shaping, rips, pattern penalty, boards). Maximise randomness orders (pattern penalty, passes, shaping, rips, boards). Validity precedes either objective. Skirting orders (passes, waste).

Measured results

Totals across the same 84 cases, September 2026:

Metric	Original	Minimise cuts	Maximise randomness
Flooring saw passes	2,177	1,741	1,994
Shaping passes	192	184	185
Rip passes	414	402	405
Pattern penalty	265	1,349	113
Flooring boards	3,561	3,537	3,579
Flooring waste	8.20%	7.57%	8.66%
Invalid cases	0	0	0

Minimise cuts saves 20.0% of saw passes. Maximise randomness reduces the pattern penalty 57.4%, while also saving 8.4% of saw passes. For random flooring in the default 4,800 × 3,600 mm room, 38 passes become 24 or 30, respectively; both options use 76 boards and have approximately 1.2% waste.

Skirting drops from 1,447 to 1,436 passes. It uses 521 boards instead of 513: cutting effort now takes precedence over waste, which rises from 9.28% to 10.68%. Eight cases improve and 76 tie. For flooring, 78 cut-priority cases improve and six tie. Appearance priority improves 72, ties 11, and uses one extra cut in rectangle-38 despite the same zero pattern penalty. The bounded search does not establish global optimality.

Iterations retained

1. Correct the objective order; measuring stock first contradicted the requested priorities.
2. Deduplicate the complete relevant state, including recent joint history. Stop computing keys once the beam is full; share immutable exhausted stocks and avoid searching offcuts for pieces requiring both factory ends.
3. Repack completed boundary blanks, reserving exact complementary factory ends first. Preserve the original placement and cutting order within each source board.
4. Try bounded swaps of interchangeable rectangular rows. Accept only a lower pattern penalty with unchanged cuts, stock and geometry coverage.
5. Polish all surviving completed candidates, retaining the best result.
6. Preserve end remnants during search instead of trimming them immediately. This alone improves 56 cut-priority cases and saves another 99 passes after the earlier improvements. Final packing can still combine non-exact blanks.
7. When repetition remains, compare an immediate-reuse search as well. This improves five appearance-priority cases. All searches share their clipping cache, and the two UI choices select from the completed results. Selection itself does not rerun the optimiser.
8. Compare exact three-piece skirting fills with the original packing. This improves two cases for a small additional calculation cost.

Experiments rejected

Increasing beam widths from 5/2 to 12/4 roughly tripled search time, with regressions in both modes. Carrying two room results into the next room worsened two appearance cases for a single waste improvement. Expanding the offcut candidate pool with distinct remnants had no cut-priority benefit and regressed a large-room result, including after the end-preservation change. These variants were removed.

The original single-result benchmark took about 1.5 seconds for the corpus. Producing both choices, including the conditional extra appearance search, takes about 3 seconds on the same machine; p95 is around 110 ms and the most complex case around 0.7 seconds. These are indicative timings, not CI thresholds. Ordinary option changes reuse the already calculated plans. A separate 500-row, 2,000-board boundary check completes without an error; temporary stock is repacked before enforcing the board limit.

Tests enforce the retained aggregate improvements as well as physical invariants. Metric definitions and input cases stay fixed while search strategies change.