Two Layer-1 generation fixes surfaced by the per-layer atlas viewer:
- Layer1Output now carries grid_w/grid_h (the downsampled working-grid the
positions live in). The client maps overlays from these, so the scale is
correct for any source heightmap resolution rather than assuming the texture
size — fixes overlays projecting at half scale into a corner.
- Drainage basin boundaries are traced as ordered, non-self-crossing contours
via Moore-neighbour tracing instead of an angle-from-centroid sort. The sort
produced star-shaped, self-crossing polygons for concave basins that rendered
as straight chords across the map.
Golden (cascade_layer1.json) and the cross-language atlas_response_ready
fixture regenerated. 100 atlas lib tests + the new tracer test pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Addresses the Hoshe (QA) + Tyre (architecture) review of the SeedChain/cascade
work:
- Golden was pinning an empty river network (128x64 produced 0 river cells).
Bumped to 256x128, where GJ1c yields a real network (93 river cells, 19
mouths) — Layer 1's rivers are now actually guarded, not just attractors.
- SeedChain::for_body(world_seed, body_id) + fnv1a_64: the single canonical
body_id(String) -> u64 path (FNV-1a, the repo convention), so callers can't
derive divergent worlds from the same seed via different ad-hoc hashes. The
golden now uses it.
- Stability guards: seed_domain_discriminants_are_pinned test (CI fails if a
SeedDomain tag is renumbered); AttractorType gains #[repr(u8)] + explicit
discriminants (it's cast as a sort key in features.rs).
- Tests: SeedChain::root(0) non-degenerate; run_cascade error path (missing
file -> Err, not panic).
- Comments: clarified the id=0 derivations (sibling separation is caller-side
via the per-district/quarter chain; #957 threads the index), tightened the
all_district_types reachability comment (it pins the seed-0 sequence, not a
probabilistic claim), and noted the golden's WORLD_SEED is cosmetic at
Layers 0-1 + the x86_64 f32 capture caveat.
Deferred with reason: the run_cascade -> CascadeInputs struct refactor (Tyre)
is left for #954 — designing Layer-2's context shape now would be later-phase
detail, and there's a single caller to migrate then. EntityRng keeps its
domainless combine (migrating is stream-changing) — noted in D-224.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
End-to-end determinism guard. cascade_golden.rs pins two artifacts for a real
committed body heightmap (GJ1c) in one diffable JSON golden
(server/tests/golden/cascade_layer1.json):
- Layer 0: SHA-256 of the source heightmap.png bytes (flips if the Python
heightmap generator or the file changes)
- Layer 1: the serialized Layer1Output of run_cascade on a 128x64 downsample
(flips if the Rust drainage/feature/sub-biome code changes)
JSON (not the msgpack discussed in refinement) to match the existing
golden_suite.rs convention and stay diffable — a failure shows what drifted.
UPDATE_GOLDEN=1 regenerates; wired into `make golden-update`.
Adds Serialize/Deserialize to RiverNetwork/DrainageBasin/Layer1Output and a
sha2 dev-dependency.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
jpmschweitzerandClaude Opus 4.7