Finding-U6 from doc/reviewer/usability-audit-2026-05-31.md.
The Finding-D fix (external-audit-2026-05-30) added a clean one-call
gauge-vertex overload:
assign_euclidean_vertex_dof_indices(mesh, maps, gauge_vertex)
But all user-facing code still showed the old verbose manual loop:
auto vit = mesh.vertices().begin();
maps.v_idx[*vit++] = -1;
int idx = 0;
for (; vit != mesh.vertices().end(); ++vit) maps.v_idx[*vit] = idx++;
Replaced in three places:
README.md 'Minimal usage' code block
example_euclidean.cpp Step 3
example_layout.cpp pin_first() helper
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
U4 (README.md:17) — status line: v0.9.0 → v0.10.0, test count 0 → 277
U5 (Discrete_conformal_map.h:6-16) — \file Doxygen block rewritten:
was: 'provides a single function … Spherical/hyperbolic scheduled for Phase 8b.2'
now: lists all three discrete_conformal_map_* functions already present,
plus pointers to the circle-packing companion headers
U7 (getting-started.md) — new 'Mode 4 — Low-memory build' section added
after Mode 3; shows CONFORMALLAB_LOW_MEMORY_BUILD=ON with -j1 and explains
the -O0 / no PCH / batch-1 tradeoffs for Raspberry Pi / ≤ 4 GB runners
U8 (README.md compile-time modes) — LOW_MEMORY_BUILD entry added to the
compile-time workflow code block with a one-line explanation and the
mandatory -j1 note
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Finding-U3 from doc/reviewer/usability-audit-2026-05-31.md.
Three concrete errors corrected:
1. check_gauss_bonnet() row (was: implies all map types work)
→ now: 'EuclideanMaps/SphericalMaps only' — HyperIdealMaps overload
is = delete (compile error since external-audit Finding-B fix)
2. enforce_gauss_bonnet() row (same issue)
→ same restriction note added
3. newton_hyper_ideal() preconditions (was: 'lambda0 initialised')
→ WRONG: HyperIdeal computes lengths from b_v, a_e via zeta functions
internally; lambda0 plays no role. Correct precondition:
'no lambda0 needed · no GB pre-check'
→ Added explanation: strictly convex energy (Springborn 2020 Thm 1.3)
→ Newton converges for any targets without a pre-check
Gauss-Bonnet prose section also updated:
- Examples now show EuclideanMaps/SphericalMaps explicitly
- HyperIdeal compile-error note added with the correct hyperbolic
identity Σ(2π-Θ_v) - Area = 2π·χ and why no pre-check is needed
- Open-mesh note added (GB identity does not hold for boundary meshes)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
U10: CLI has no parameter reference in README or getting-started.md.
Documents all 7 current flags with defaults in the audit file so
a future session can add the table to getting-started.md.
U11: Three useful CLI gaps documented as a roadmap item:
- --tol / --max-iter: Newton solver tuning, currently hardcoded
- -g cp_euclidean / -g inversive_distance: Phase-9a models not
reachable from CLI despite being fully implemented in the library
Each item has an effort estimate (~30 min / ~2 h) and concrete
acceptance criteria so a future session can pick it up cold.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Finding-U1 and Finding-U2 from doc/reviewer/usability-audit-2026-05-31.md.
The existing examples (example_euclidean, example_layout, example_hyper_ideal)
all used the "natural theta" pattern which makes x*=0 trivially the
equilibrium — u_v ≈ 0 everywhere, no deformation. A new user following
these examples saw solver output but not conformal geometry.
New: example_flatten.cpp
- PRIMARY USE CASE: conformally flatten a mesh to the plane
- Sets Θ_v = 2π for all interior vertices (flat target)
- Pins boundary vertices (no Gauss-Bonnet check for open meshes)
- Demonstrates non-trivial u_v (cathead.obj: range ≈ 2.96, 5 Newton iters)
- Documents the difference from "natural theta" explicitly
New: example_cgal_api.cpp
- Demonstrates CGAL::discrete_conformal_map_euclidean (Discrete_conformal_map.h)
- First runnable CGAL public API example; contrast with internal API
- Documents the "natural theta" default behaviour and explains why u_v=0
- Explains when to use CGAL API vs internal API
Both examples registered in code/examples/CMakeLists.txt and compile
cleanly with -DWITH_CGAL=ON.
Updated:
- example_euclidean.cpp: prominent "TESTING CONVENTION" warning
- example_layout.cpp: same warning on set_natural_theta helper
- doc/getting-started.md: example_flatten is now the recommended
"start here" example; note on natural-theta behaviour added
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
External documentation and usability review of v0.10.0.
9 findings covering documentation correctness, API usability,
and new-user experience.
Critical:
U1 — All examples show trivial identity map (natural theta),
not real conformal flattening — new users see no-op output
U2 — CGAL public API has zero runnable examples
Medium:
U3 — contracts.md incorrect: check_gauss_bonnet row missing
HyperIdeal restriction (deleted overload after Finding-B)
U4 — README still shows v0.9.0 (current: v0.10.0, 277 tests)
U5 — Discrete_conformal_map.h header comment describes Phase-8a
state; all 5 entry functions already implemented
U6 — New gauge-vertex overload (Finding-D) not reflected in
README or examples — old verbose loop still shown
Minor:
U7 — CONFORMALLAB_LOW_MEMORY_BUILD absent from getting-started.md
U8 — CONFORMALLAB_LOW_MEMORY_BUILD absent from README table
U9 — Layout2D.uv index semantics undocumented (v.idx() contract)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
