T-988 — BuildingExteriorTag {wall_material, roof_form, facade_rhythm,
setback_tier, color:HsvColor, street_surface}. New trait_exterior.rs:
3-step era-free derivation (visual_bundle filter -> zone-bias weighted
pick -> density->setback), color seed-sampled within the register band.
Resolved at GenerateSkeleton plan time (T-994 precedent), frozen on
BuildingPropertyTag; FillChunk only reads it. Four append-only
integer-discriminant enums (WallMaterial/RoofForm/FacadeRhythm/
StreetSurface), unknown token -> axis Generic + warn. trait_catalog_reader
now parses visual_bundle + the two new tables (OnceLock-cached).
New SeedDomain::TraitExterior (per-axis sub-chains — no cross-field
correlation).
T-959 — FillChunk reads the frozen exterior tag: wall_material/roof_form
onto Wall/Roof shell voxels (FilledChunk.surface_material). Additive,
ShellVoxel untouched, all shell tests pass. (Interstitial-fill-from-setback
split to T-1098 — needs a FillChunk block-metadata + geometry design pass;
nothing consumes FillChunk until Phase 5.)
T-1097 — BlockSkeleton.interstitial_character (OpenSpace|OperationsSurface),
D-233 bulk-driven: bulk-industry blocks' non-roofed remainder tags as built
economic infrastructure, not generic open space.
cargo check --all-targets clean; 1666 lib tests pass; no golden impact
(harnesses top out at CascadeLayer::RoadGraph, unreachable by Layer 4/5).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
T-994 — three-phase draw replacing the flat splitmix64 flavor pick:
- Phase 1 body K-draw (trait_draw.rs): hard gates -> soft weights (two-part
geographic_sector join, PR #148) -> SeedChain::for_body-seeded weighted
draw of K (5/3/1/0 by ComplexityTier), pins count toward K, coverage-aware
over a new body-level district-type-mix aggregate threaded into
CityGenerationContext at L3->L4 dispatch.
- Phase 2 district-dominant pick keyed by the D-243 2048m District cell —
settlements sharing a cell independently derive the identical template.
Resolved at dispatch, never in FillChunk (T-987 stays pure).
- trait_catalog_reader.rs: systems.db reader for trait_templates +
atlas_body_trait_bias (D-225 resource pattern), registered in main.rs
with graceful degradation.
- BlockSkeleton carries district_type; assign_block_tags is a pure lookup.
T-1003 — deviation/swerve system (trait_swerve.rs):
- ArchitectureFlavorRef is now InVocabulary(u8) | Swerve(tag).
- Rare per-building wildcard: foreign-import pool (other corridors +
cross_corridor) driven by Epicenter/Passage tier, mixed faction,
road-graph degree; heritage-callback pool (own-corridor heritage) driven
by isolation, remote tier, founding_age_years. Integer bps, base 100,
cap 300 per driver — placeholder constants pending calibration.
- Sparsity escape hatch = same mechanism, necessity-triggered at the
phase-2 pick (deterministic max-weight over the hard-gate-eligible pool).
- New SeedDomains: TraitVocabulary(13) / TraitDistrict(14) / TraitSwerve(15).
Governance: D-232 amended (district pinned to the D-243 2048m tier — the
D-222/D-243 redefinition was never captured; swerve driver mappings +
placeholder rates recorded), D-229 flavor_ref field updated to the enum
shape, D-235 amended (T-995 vocabulary ratification note; rides here due
to single-file entanglement).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Implement the D-230 on-demand derive phase (data-production half). New
atlas/shell.rs derives a sparse building shell for one 64 m chunk from the
plan-phase BuildingPropertyTags: rectangle-containment (footprint ∩ chunk) ×
z-range (per-floor voxel bands from FloorExtent), in a quarter-ground z frame
(D-110). Walls on the footprint perimeter, FloorSlab on interior floor bases,
Roof above the top floor; interior air is Void and never stored.
- gen_queue.rs: GenWorkItem::FillChunk carries pre-resolved block_tags +
block_pos + sub_chunk (run_work_item stays cache-free, mirroring
GenerateSkeleton); GenCompletion::ChunkFilled carries Box<FilledChunk>; the
arm calls shell::fill_chunk; pure build_fill_chunk_item(&QuarterWorldState,..)
added.
- plugin.rs: ChunkFilled handler accepts the shell (trace-only — the Phase-5
rendering consumer and the on-demand streaming dispatch trigger are deferred;
do not build on legacy chunk_streaming.rs before Phase 5, gated by T-962).
Tests: determinism, sparsity-vs-dense-volume, wall/floor/roof correctness,
basement z-origin, sub-chunk clipping, full submit→drain→ChunkFilled round-trip.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>