[altvnk]

Scoped completion claim

Units: curve.curve_p7.

In scope: one genuine fixed canonical Ellipse input and a successful
GlobalPropertyAnalysis(PlaneClassify) regression with complete geometric comb.
This adds concrete-kind/virtual-dispatch coverage to an existing algorithm, not a
new ellipse-specific algorithm. Existing circle shorthand remains a B-spline.

Expected edits:

• crates/difftest/src/units/curve_curve_p7.rs
• crates/solidcore-ffi/src/units/curve_curve_p7.rs
• harness/cpp/shim/curve_curve_p7.cpp
• fixtures/curve.curve_p7/analytic-plane-classification.json

Evidence: inspected main b206d3f5a38127dc3a0b6c511f1b45116826b341 has no
ordinary real-Ellipse constructor in this unit. A bounded noncanonical Rust probe
constructed the actual semiaxes-3/2 ellipse over angular [0,180], natural NURB
[0,1], classified y-1=0, and produced one ordered positive arc plus 150 comb
points and 150 vectors. Endpoints lie near (±2.598076211353316,1,0), midpoint
y=2. This probe is not C++ parity or a fresh-head build.

Reviewed protocol: fixed canonical origin/X/Y/radii/extent, no geometry payload,
new ordinary block [3,3] (kind/dimension). Use genuine Ellipse constructors in
both engines through the existing generic curve route and positions, preserving
old kinds 0–2, cache guards and transform bounds. Admit the new inherited
B-spline-backed capability without relaxing old Hermite/Line restrictions or
adding an operation-specific whitelist. Preserve the existing three-vector guard;
the fixture pads unused vectors rather than narrowing that validation.

Validation planned: fixture discovery/exact encoding/real-kind/domain tests;
successful range geometry and all ordered comb points/vectors; full 916-value
native output plus status; interior-comb perturbation; new-kind generic parser
admission and old-error-order controls; full unfiltered affected unit and
perturbation; formatting and CPP-enabled Clippy; independent final-diff review;
all canonical current-head native/value-share/exact-base gates. Compile the modified
shim against the existing reference libraries read-only, never a stale executable.

Preserve all old fixtures, generated inputs, RNG draws/seeds/minimum 3000, guard
decisions/error ordering for old kinds, result layouts, mismatches, formulas,
tolerances, floors and status. No production test/file, shared helper/interface,
cache, plan, workflow, reference-library or old-fixture edits. Any native mismatch
or extra production need blocks this coverage-only scope; do not hide it by
changing inputs, introducing deferrals or weakening validation/comparison.

Related PRs / dependencies: #1048 owns p4 distance-equation coverage, #1047 p6
Sphere coverage, #1041 p9 diagonals; all are independent unit-local paths.
#686 ellipse STEP and #1031/#1042 cache/interfaces remain untouched.
Available follow-ups: CCI and transformed-ellipse success paths are not newly
demonstrated by generic admission and are not reserved by this fixture scope.

Status / blockers / next step: scoped draft; implement only the reviewed four paths,
establish native parity, then await exact-head canonical CI. Maintainers retain
workflow authorization, approval, queue admission and merging.

Published draft: exact-head evidence

Head 96fdbdf9c051ad7a803d0ddc713f563f2f579d7a, safely synchronized with authoritative main f4d002bb0a6dc5d49928a80213eb9ade8cdab7bd.
Independent final source gate accepted fingerprint e0a2bf10613ccc66821fd06787a89dee3ec6c8ccdbad7cf88ba94300e2b783d3;
reviewed binary PR diff unchanged across safe upstream merge. All66oldfixtures,
minimum3000generated cases, RNG/seed inputs, guards and result layout are preserved.

7 focused CPP runner tests passed, including actual ffi::validate admission tests
PASS curve.curve_p7 cases=3067 passed=3067 failed=0 deferred=0 max_rel_err=0e0 with_values=3067 no_values=0 vacuous=0
SENSITIVE curve.curve_p7 perturbed=3067 detected=3067 unperturbed=0 deferred=0
CPP-enabled Clippy both changed Rust crates all-targets -D warnings: PASS
workspace formatting and diff checks: PASS

Operation / symbols	Implementation	Successful native comparison	Remaining gap
Real Ellipse GlobalPropertyAnalysis(PlaneClassify), named upper-arc fixture	Generic fixed canonical Ellipse leaf in unit-local builders, existing algorithm unchanged	Status plus complete916ordered values compare, including one positive upper-arc range and150points/150vectors; endpoint plane/ellipse residuals and interior comb perturbation checked	Concrete-kind dispatch coverage only, not a new ellipse algorithm; CCI/transformed-ellipse successful geometry not newly demonstrated

The existing THREE-vector guard is retained; unused fixture vectors are padded.
Comb samples cover the full natural interval in order, not only the retained arc.
Perturbing only sample75 comb-Y out[692] is detected with status/counts/range intact.
Protocol admission tests reside in this unit's runner and invoke real ffi::validate;
a prior separate FFI-package filter matched zero tests and is NOT counted as proof.
Identical match arms were consolidated without changing generator/RNG behavior.

Shared reference hashes/mtimes unchanged, no rebuild. This is local macOS evidence;
canonical Linux/default-workspace/value-share/exact-base gates remain mandatory.
Ready for review by explicit user instruction; canonical CI is still pending.

User-authorized review status

Marked ready for review at the user’s request after local native validation and independent source review. Canonical CI was authorization-blocked at the latest audit; this transition does not claim green CI, approval, queue admission or merge readiness. Maintainer workflow authorization and all required checks remain mandatory. No source commit or workflow configuration changed.

[altvnk]

@bherbruck — exact published draft head 96fdbdf9c passed independent final source review,7focusedCPPtests (including actual FFI-admission checks), full native curve.curve_p7 3067/3067 cases, perturbation3067/3067, CPP-enabled Clippy and formatting. The real-Ellipse fixture compares all916ordered values plus status and detects an interior-comb-only change. Old fixtures/generator inputs/RNG/guards/tolerances remain unchanged. Canonical run40249056438 requires authorization and has executed zero jobs. Please inspect/authorize it; the PR remains draft pending all13canonical jobs/native/value-share/exact-base retention. No technical CI failure or merge-readiness claim.

[bherbruck]

Approved by the automated first-pass review: CI green, mergeable, no CI/build/dependency file changes, no red-flag patterns in added code (process/network/env/unsafe outside FFI/blobs/hidden unicode), 0 known-mismatch entries added. Logic is gated by CI and the difftest merge queue.