settled-reach/docs/assets/briefs/rural-walls.md

title, description, type, status, ticket, decision_refs, author, created, updated

title	description	type	status	ticket	decision_refs	author	created	updated
Asset Brief — Rural Walls	Building-exterior wall models/textures for rural/vernacular settlement types — D-235 wall axis	design	active		D-235 D-244 D-257	Araminta	2026-07-25	2026-07-25

Asset Brief — Rural Walls

One page. Gates its child story — the story does not enter in_progress without this brief attached.

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1. Scope

Building-exterior wall surfaces for rural/vernacular/frontier settlement types — the D-235 WallMaterial axis tags a rural-type template's allow filter selects (stone_wall, timber_wall, rammed_earth_wall, stucco_wall, brick_wall — the "vernacular/agrarian" register). No prior art exists for this class beyond the T-961 epic text mention (2026-06-12 audit matrix) — unlike station-walls.md's sibling, this is a clean-slate brief. Out of scope: station/urban walls (concrete_wall, steel_frame, glass_curtain_wall, composite_panel — sibling brief), barns (a rural building type, not a wall-axis token — deferred, see deferred.md), doors, floors.

2. Visual Reference

palette.md §3.1 rows for stone_wall, timber_wall, rammed_earth_wall, stucco_wall, brick_wall — every one of these tags is explicitly warm-hued (warm grey-tan, warm mid-brown, ochre-to-umber banding, warm off-white sand, warm terracotta-to-ochre) and the table is explicit that stone_wall is D-235's flagship "gets it wrong if literal" case — never render it cool grey. This is the register where the "functional warmth" mood target (palette.md §4) reads most directly — rural walls are the class most likely to be mistaken for a generic cool-grey default if a generation pass isn't told otherwise. generic_wall (§3.5) is the shared fallback terminal with station-walls.md — one placeholder texture serves both siblings until specific tags ship.

3. Naming

Texture: <object_tag>_<map_type>.png per conventions.md §3 — e.g. stone_wall_basecolor.png, stone_wall_normal.png, timber_wall_basecolor.png, rammed_earth_wall_basecolor.png. If a standalone wall-segment model is produced (rural walls are more likely to need a discrete model than station walls, given rammed-earth's strong horizontal banding reads better as geometry+texture than texture-only), it follows §1's <category>_<descriptor> .glb (e.g. wall_structural_timber.glb) with the same props-category placement as its station sibling. No tint mask — material register (not player-favorite color) drives these hues.

4. Generation Path

Standard path: /image-gen → /glb-gen (Trellis) → Blender postprocess → client/assets/models/props/ + manifest.json, OR the texture-only path (/image-gen concept, no Trellis step) landing in textures.md — same choice as station-walls.md §4, decided per-tag based on whether the material's character (rammed-earth banding, stone coursing) needs real geometry or reads fine as a flat PBR map. Concept prompts for this class should explicitly state the target hue family from §2 (warm, not cool-grey) since Gemini's default "concrete/stone" association skews cool without that steer.

5. Acceptance

3 starter assets enter models.md/textures.md + manifest.json at planned: (1) stone_wall texture — the flagship warm-hue worked example, highest risk of a cool-grey miss without explicit review; (2) timber_wall texture; (3) rammed_earth_wall texture (the banding signature makes it a good early test of whether the texture-only path is sufficient or a modeled relief is needed). generic_wall is shared with station-walls.md — do not duplicate it in this class's count; milestone-0 IF Q-119 resolves yes (not resolved here).

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Cross-References

• docs/assets/visual/conventions.md §1, §3 — model naming, D-235-keyed texture naming
• docs/assets/visual/palette.md §3.1, §4 — wall material register, "functional warmth" mood target
• docs/assets/visual/models.md, docs/assets/visual/textures.md — target catalogs
• client/assets/models/manifest.json
• docs/assets/briefs/station-walls.md — sibling brief, shares generic_wall fallback