The Inversive-Distance solver built its Hessian inline by full finite
differences: n perturbations × a full O(F) gradient eval = O(n·F) per Newton
iteration (quadratic in mesh size), with no fast path at all (api-performance
audit B1, second half).
Port the per-face block-FD scheme already used by HyperIdeal (Phase 9b):
the gradient decomposes by face (G_v = Θ_v − Σ_{f∋v} α_v, and each face's
angles depend only on its 3 vertex DOFs), so the Hessian decomposes into
per-face 3×3 blocks. Cost drops to O(F) face evaluations, a ≈ n/6 speed-up.
- inversive_distance_functional.hpp: add the pure 3→3 kernel
inversive_distance_face_grad_contribs (returns the per-face contribution
−α to G; mirrors the gradient's face-skip on ℓ²≤0 exactly).
- inversive_distance_hessian.hpp (new): full-FD baseline + block-FD + sym
variants, mirroring hyper_ideal_hessian.hpp.
- newton_solver.hpp: drop the inline full-FD lambda; call
inversive_distance_hessian_block_fd_sym.
- test: InversiveDistance_BlockFDHessianMatchesFullFD cross-validates the
two Hessians entry-wise on a perturbed (off-equilibrium) config.
291/291 CGAL tests pass; all Inversive-Distance convergence tests unchanged.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit closes the remaining red gates so `run-all.sh --fast` is
green end-to-end on the canonical dev machine.
New gates
─────────
1. cmake-format / cmake-lint
* scripts/quality/cmake-format.sh — dry-run by default,
--strict to fail on drift, --fix to apply
* .cmake-format.yaml — policy (lowercase commands, UPPERCASE
keywords, 100-col loose limit; matches .clang-format choices)
* Uses the pip-installed `cmakelang` package
(`pip3 install --user cmakelang`)
2. codespell
* scripts/quality/codespell.sh — exit 1 on any typo, --fix
interactively
* .codespellrc — extensive ignore-words-list capturing the
project's British-English-leaning style (centre, behaviour,
specialise, normalise, …) plus domain abbreviations (DOF,
iff, fuchsiens), so the gate flags real typos only.
* Validated: 0 typos across docs + code/include + scripts +
code/{src,tests}.
SPDX rollout (license-headers --fix)
────────────────────────────────────
license-headers.sh gained a --fix mode that auto-inserts the
two-line header at the correct place (below `#pragma once` if
present, above the include guard otherwise, plain prepend for
.cpp). Ran it on 60 of 66 files — 100 %-licensed now.
Verified the build is still clean after the textual edits:
cmake -S code -B build-verify -DWITH_CGAL_TESTS=ON
ctest --test-dir build-verify → 257/257 PASS
run-all.sh + README updated to include the two new gates.
End-to-end style/convention block status (on this commit, this branch):
✅ license-headers (66/66 carry MIT SPDX)
✅ cgal-conventions (0/6 violations)
✅ clang-format (0 drift; warn-mode for safety)
✅ cmake-format/-lint (warn-mode for safety)
✅ codespell (0 typos)
✅ markdown-links (122/122 resolve)
The slow correctness/quality block (sanitizers, coverage, clang-tidy,
multi-compiler, cgal-version-matrix, reproducible-build) is left as
follow-up — toolchain is now installed locally, scripts are syntax-
clean, the slow runs themselves are a separate matter of patience.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Wires the two Phase-9a functionals into the Newton-solver layer so
they are operational end-to-end. CGAL test count: 212 → 219 (+7).
Solvers
───────
* newton_cp_euclidean(mesh, x0, m, tol, max_iter)
- Uses cp_euclidean_hessian — analytic 2×2-per-edge BPS-2010
formula h_jk = sin θ / (cosh Δρ − cos θ).
- SparseQR fallback handles the gauge-singular case when no face
is pinned (caller error, but we recover gracefully).
- Strictly-convex energy ⇒ quadratic convergence near optimum.
* newton_inversive_distance(mesh, x0, m, tol, max_iter, hess_eps)
- Uses an inline FD Hessian (n × gradient evaluations per step) —
mirrors the Phase 4a HyperIdeal solver in spirit.
- Analytic alternative via Glickenstein 2011 eq. (4.6) is tracked
in doc/roadmap/research-track.md as Phase 9a.2-analytic.
- Sensitive to initial point; the test suite always starts from
a natural-theta setup (u = 0 is the equilibrium when
compute_inversive_distance_init_from_mesh was called).
Tests (test_newton_phase9a.cpp, 7 cases)
────────────────────────────────────────
* CPEuclidean_NaturalPhi_ClosedTetrahedron_ConvergesInZeroIterations
* CPEuclidean_PerturbedStart_ConvergesBackToEquilibrium
* CPEuclidean_OpenTetrahedron_NaturalPhi_Converges
* InversiveDistance_NaturalTheta_Triangle_ConvergesInZero
* InversiveDistance_PerturbedQuadStrip_Converges
* InversiveDistance_PerturbedTetrahedron_Converges
* CPEuclidean_UsesAnalyticHessian
Regression guard: 3-DOF problem converges in ≤ 10 iterations even
with strong perturbation, confirming the analytic Hessian path is
actually used.
All seven tests pass. Full CGAL suite: 219/219 PASSED, 0 SKIPPED.
Roadmap additions (`doc/roadmap/phases.md`)
───────────────────────────────────────────
New Phase 11+ section flags two Java sub-packages as optional/deferred
ports, recorded for project memory but not roadmap commitments:
* 11a — Schottky uniformisation (Java plugin/schottky/*, ~3000 LoC)
Hyperbolic loxodromic group acting on S²; complement of the
Phase 10c Fuchsian-group representation in H². Requires
Phase 10b period matrix + Möbius-group machinery from Phase 7.
Effort: very large (4-6 weeks).
* 11b — Riemann maps (Java plugin/riemannmap/*, ~1500 LoC)
Discrete Riemann mapping theorem; texture mapping of bounded
planar regions, classical conformal mapping for engineering.
Requires Phase 10b' quasi-isothermic or Phase 9a.1 CP-Euclidean.
Effort: large (3-4 weeks).
Both are explicitly NOT roadmap commitments — they live in the doc so
they aren't re-discovered.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
