822a27da69
Upgrades the cyclic Euclidean Hessian from block-FD to closed-form, satisfying
the novelty-statement §3.2 "analytic Hessians, not finite difference" claim for
the Euclidean path.
- euclidean_hessian.hpp: `euclidean_hessian_analytic` — closed-form cyclic
Hessian from the law-of-cosines angle derivatives
∂α_i/∂s_i = ℓ_i²/4A, ∂α_i/∂s_j = ½cot α_i − ℓ_j²/4A (Σ_j = 0),
chained to (u, λ_e) and sign-mapped to the gradient outputs (−α vertex,
+α_opp edge). Reuses euclidean_cot_weights. Block-FD kept as cross-check.
- newton_solver.hpp: newton_euclidean cyclic path now uses the analytic Hessian.
- tests: CyclicHessian_Analytic_MatchesBlockFD_Tetrahedron — analytic == block-FD
(1e-6), == gradient FD (1e-5), symmetric (1e-9). Existing cyclic convergence
oracle still GREEN with the analytic Hessian routed in.
Tier-2 (Wente) finding: wente_torus02.obj is a QUAD mesh (1240 quads) and the
Java golden comes from cyclic (quad-net) uniformization; the C++ period-matrix
pipeline is triangle-based, so a faithful bit-vs-Java τ comparison needs a
quad/cyclic pipeline (Phase 9f). Deferred and documented; golden τ = ½+i√3/2.
244/244 cgal tests pass.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Reviewer meeting materials
A single landing page for the three documents associated with an external-reviewer meeting. The materials are written for a peer who actively publishes in discrete differential geometry — specifically the decorated-DCE / Penner-coordinates / hyperideal-polyhedra / canonical-tessellations research line — and who would potentially use conformallab++ as numerical infrastructure for their own future experiments.
| Document | Audience | Purpose |
|---|---|---|
briefing.md |
the reviewer | one-page orientation: what the project is, where to look first, what we want from them |
questions.md |
the reviewer | the 5 concrete decisions we want their opinion on (skim before the meeting) |
agenda.md |
me | my own meeting playbook: timing, order, the "no" question, post-meeting memo template |
After the meeting, a fourth file 2026-XX-XX-meeting-notes.md should
land here too — the memo template at the bottom of agenda.md is the
suggested structure.
When to send to the reviewer
- briefing.md + questions.md: as part of the meeting-confirmation email, ~5 business days before the meeting. Subject line: "Pre-read for our conformallab++ chat (~15 min)".
- agenda.md: never send. This is internal scaffolding.
Hub-Page durability
The reviewer hub HTML at https://tmoussa.codeberg.page/ConformalLabpp/
is published from doc/reviewer/hub.html in the repo (not from a
detached preview branch). This means:
- Merging any of the open PRs into
maintriggers.gitea/workflows/doxygen-pages.ymlwhich republishes the hub alongside fresh Doxygen HTML — the reviewer URL stays live across merges with no manual intervention. - The hub is source-controlled, so changes are reviewable via PR like any other doc, and old versions live in git history.
- The original Doxygen index moves to
/doxygen.htmlwhenever the hub override is active; both are reachable from the hub itself.
Quick links the reviewer should bookmark
- 🌐 Reviewer-hub landing page: https://tmoussa.codeberg.page/ConformalLabpp/ (the hub shows status badges, a "what's new" banner with the most recent delta, the research-alignment table, and direct links into every document below)
- 📦 Source: https://codeberg.org/TMoussa/ConformalLabpp
- 📝 Architecture decisions (incl. the Q7 "no" prompt):
../architecture/locked-vs-flexible.md - 📐 Schläfli derivation (for Q3):
../math/hyperideal-hessian-derivation.md - 📚 Literature index (for Q1 + Q3):
../math/references.md - 🗺️ Per-phase roadmap (for Q1):
../roadmap/phases.md - 🧪 Research-track entries with acceptance criteria (Q1 + Q2):
../roadmap/research-track.md