Adds `operator|` in `namespace CGAL` so package-local named parameters
can be combined left-to-right without modifying CGAL upstream:
auto p = CGAL::parameters::gradient_tolerance(1e-12)
| CGAL::parameters::max_iterations(500)
| CGAL::parameters::output_uv_map(uv);
CGAL::discrete_conformal_map_euclidean(mesh, p);
Why not the canonical `.a().b().c()` syntax
───────────────────────────────────────────
CGAL's standard chaining mechanism requires registering each named
parameter as a member function on `Named_function_parameters` via the
`CGAL_add_named_parameter` macro in
`CGAL/STL_Extension/internal/parameters_interface.h` — a vendored
upstream file that conformallab++ deliberately treats as read-only.
Adding member-function chainers for our package-local tags would
require either forking CGAL or modifying the vendored copy. Neither
is acceptable for a library that wants to remain portable across
future CGAL releases.
The pipe-operator achieves the same compositional semantics via a
free function in `namespace CGAL` (so ADL finds it for
`Named_function_parameters` operands). Implementation: rebuild the
right-hand-side `Named_function_parameters` with the left-hand-side
as its `Base`, producing an indistinguishable chain that every entry
function accepts unchanged.
Implementation: `code/include/CGAL/Conformal_map/internal/parameters.h`
lines 158-187. The operator is constrained to right-hand-sides with
`No_property` base (i.e. fresh single-parameter packs from the helper
functions), so it never collides with any future CGAL operator on the
same type.
Tests (2 new, total Phase-8b-Lite suite 15 → 17)
────────────────────────────────────────────────
* CGALPhase8bLite.NamedParamPipe_MultipleParamsTakeEffect
Chain three parameters; verify all three take effect (tight
tolerance respected + UV pmap populated + iteration cap honoured).
* CGALPhase8bLite.NamedParamPipe_TwoParams
Chain two parameters; verify max_iterations(0) blocks the loop
even when combined with another param.
Full CGAL suite: 234/234 PASSED, 0 SKIPPED (was 232).
Total: 257/257 PASSED, 0 SKIPPED (was 255).
scripts/check-test-counts.sh: OK.
Documentation updates
─────────────────────
* doc/tutorials/add-output-uv-map.md §3.4: "Current limitation: no
chaining" → "Chaining: use the pipe operator `|`". Explains why
CGAL's `.member()` syntax isn't available and shows the `|`
workaround with a working code example.
* doc/architecture/locked-vs-flexible.md §8: chaining now flagged as
shipped via pipe; recommended posture says `.member()` chaining
only if a user pushes for the CGAL-canonical syntax.
* doc/roadmap/porting-status.md §5: API limitations table updated.
* doc/api/tests.md: CGALPhase8bLite row 15 → 17, total 232 → 234.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
External-reviewer-visit prep package (Springborn-Bobenko PhD alumnus,
2026-05-26). All five documents target the same audience: a
mathematician who wants to evaluate, extend, or contribute to
conformallab++. Goal: make the project maximally hackable BEFORE the
meeting. Code unchanged in this commit — pure documentation.
Files added
───────────
1. **doc/tutorials/block-fd-hessian.md** (460 lines)
Step-by-step tutorial on the per-face block-FD Hessian pattern
shipped in Phase 9b (96× speed-up). Matches the style of
add-inversive-distance.md. Covers:
* The per-face locality lemma (mathematical justification).
* Cost analysis (full-FD vs block-FD vs analytic).
* Implementation walkthrough through face_angles_from_local_dofs +
hyper_ideal_hessian_block_fd.
* Porting checklist for applying the same pattern to a new
functional.
* The four cross-validation criteria.
* When NOT to use block-FD + upgrade path to Phase 9b-analytic.
2. **doc/tutorials/add-output-uv-map.md** (477 lines)
Tutorial for the `output_uv_map` named-parameter pattern shipped in
PR #14. Covers:
* The UX problem (two-step pipeline → one-call wrapper).
* The CGAL named-parameter mechanism + how the entry functions
wire it (get_parameter + constexpr if).
* Step-by-step recipe for adding a new named parameter (worked
example: hypothetical `output_holonomy_map`).
* The five test patterns for verification.
* Why CP-Euclidean (face-DOF) and Inversive-Distance (Luo-edge-length)
do not yet support output_uv_map — what is needed to add them.
3. **doc/math/hyperideal-hessian-derivation.md** (805 lines)
Research-quality LaTeX-formatted derivation of the analytic
HyperIdeal Hessian via the Schläfli identity (Phase 9b-analytic
preparation). Covers:
* Schläfli identity (1858/60) — gradient and second-order form.
* Derivatives of ζ, ζ₁₃, ζ₁₄, ζ₁₅ (all hyper-ideal-to-fully-ideal cases).
* Chain rule for ∂β_i/∂(b,a) and ∂α_ij/∂(b,a) — case-split on the
four α_ij branches.
* Per-face 6×6 block formulas.
* Acceptance criteria for the future implementation.
* Implementation outline (Conformal_map header sketch).
* Appendix A: sign / argument-order pitfalls reading the code.
* References: Schläfli 1858, Milnor 1982, Vinberg 1993, Cho-Kim 1999,
Rivin, Glickenstein 2011, Springborn 2020, BPS 2015.
4. **doc/roadmap/porting-status.md** (~250 lines)
Operational snapshot of "where is each piece of Java math today"
at v0.9.0. Sections:
* 25 000 lines of Java in one table (ported / worth porting /
intentionally skipped breakdown).
* Five DCE models — full status matrix with Java port status,
Hessian type, Newton support, CGAL entry, UV-output capability.
* Topology + solver infrastructure status.
* CGAL public API map + known limitations (no chaining, Surface_mesh
only, submission-readiness gaps).
* Reverse cross-reference: Java class → C++ port location (or
"skipped: replaced by …" / "in roadmap: phase X").
* Things in C++ that the Java original does NOT have (research
extensions track).
* "How to use the library today" quickstart.
5. **doc/architecture/locked-vs-flexible.md** (~270 lines)
12-item architecture-decision review with tier classification
(🔴 load-bearing / 🟡 semi-fixed / 🟢 opportunistic). Each item
includes: locked-since date, cost to change, when to revisit,
recommended posture for new contributors. Key insight stated up
front: "the load-bearing decisions are all good in 2026". Closes
with five open questions for the external reviewer — items where
a second opinion would genuinely help (Phase 9c algorithm choice,
Phase 10a priorities, analytic-Hessian payoff justification,
CGAL upstream vs independent distribution, geometry-central
cross-validation).
Total: ~2 250 lines across five new docs.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
doc/api/headers.md — all 24 public headers with descriptions
doc/api/tests.md — 26 test suites, individual counts, run instructions
doc/architecture/design-decisions.md — 5 key design choices with rationale
doc/architecture/project-structure.md — full directory tree + build targets
README + overall_pipeline.md link tables updated.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
README.md: reduced from 703 to ~75 lines — what/why, status, quick
start, minimal usage example, navigation table to doc/ files.
doc/architecture/overall_pipeline.md: trimmed — roadmap, extension
points, declarative pipeline YAML, and references sections removed
(each now has its own dedicated file). Replaced with a link table.
New files:
doc/getting-started.md — build modes, single-test invocation, CLI
doc/api/pipeline.md — full pipeline API with code for all 3 geometries
doc/api/extending.md — new functionals, geometry modes, Java porting guide
doc/api/contracts.md — processing unit preconditions/provides table
doc/api/cgal-package.md — Phase 8 CGAL package design + YAML pipeline (TODO)
doc/math/geometry-modes.md — Euclidean/Spherical/HyperIdeal comparison
doc/math/references.md — all papers by module
doc/roadmap/phases.md — Phases 1–10 with porting/research boundary
doc/roadmap/java-parity.md — Java vs C++ feature parity table
doc/contributing.md — language policy, test standards, release flow
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Structured the development roadmap into four blocks with an explicit
boundary marker separating direct Java ports (Phase 1–7) from
infrastructure (Phase 8), remaining porting (Phase 9), and new
research territory (Phase 10+).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
README:
- Neuer Einstieg mit vollständiger Dissertation-Referenz (Titel, TU Berlin 2016,
DOI 10.14279/depositonce-5415, CC BY-SA 4.0)
- Links zu Original-Java-Repo, sechel.de und linkedin.com/in/sechel
- Neuer Abschnitt "Ursprung & Danksagung" vor der Lizenz
doc/architecture/overall_pipeline.md:
- Neuer "Origin"-Abschnitt ganz oben mit vollständiger Quellenangabe
- Literaturabschnitt erweitert: Dissertation als "Primary source" hervorgehoben,
Java-Original-Repo als direkter Port-Bezug dokumentiert
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Ersetzt den generischen Geometry-Framework-Entwurf durch eine präzise
Beschreibung der tatsächlichen konformen Geometrie-Pipeline:
- Klare Positionierung: spezialisiertes Werkzeug für diskrete konforme
Abbildungen, kein generisches Mesh-Processing-Framework
- Korrigiertes Mermaid-Diagramm: alle 3 Phasen mit realen Komponenten
(load_mesh → setup_maps → GB-check → Newton → CutGraph → Layout →
halfedge_uv → Holonomie → Periodenmatrix → Fundamentalbereich → Export)
- Preconditions/Capabilities-Tabelle für alle Processing-Units
- Drei Geometrie-Modi (Euklidisch/Sphärisch/Hyper-ideal) im Vergleich
- MobiusMap, halfedge_uv, Priority-BFS, SL(2,ℤ)-Reduktion dokumentiert
- Realistischer YAML-Pipeline-Entwurf als Phase-8-Ziel (Tokens statt Prosa)
- Erweiterungspunkte: neues Funktional, neue Geometrie, neues Unit
- Alle Literaturverweise direkt auf Implementierungsstellen gemappt
- "Nice To Have but maybe too much" komplett entfernt
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
