# Materials

## Constitution

Materials translate environmental light into a shared world. They must remain recognizable across scale and Design while allowing the Scene to tint reflection, shadow and atmosphere.

## Canonical responses

- **Carved stone:** broad value blocks, chipped or softened edges, dark crevices, restrained specular response.
- **Dark wood:** directional grain, warm reflected light, eased handled edges, scratches following grain.
- **Aged brass:** dark recesses, rubbed warm edges, restrained tarnish; never chrome or uniformly gold.
- **Restrained gilding:** thin sun-gold finish over a darker structural substrate; reserved for meaningful edges and celestial or civic detail, never broad sovereign coverage.
- **Enamel:** deep teal body, narrow glasslike rim, sparse fine wear; used as identity-bearing inset.
- **Glass:** environment-colored transmission and readable rim; highlights must not erase what is behind it.
- **Textile:** soft value rolloff and visible weave at focus scale; folds follow use and gravity.
- **Leather:** warm crease and handled-edge response; not plastic.
- **Ceramic:** soft glaze rolloff and fine crazing at focal scale.
- **Foliage:** clustered planes, cool shadow interior, warm transmitted edge, feathered silhouette.
- **Water:** sky reflection plus local depth color; ripple frequency follows scale and current.
- **Fire:** bright cream core, candle-gold body, sunset-amber smoke reflection; physically soft falloff.

## Material regions

Complex Components declare named regions such as `body.stone`, `trim.brass`, `inset.enamel`, `lens.glass` and `cushion.linen`. Scene Design may tint approved regions while identity-lock regions remain unchanged.

## Wear hierarchy

Wear follows cause: feet, hands, weather, water, heat, age and maintenance. Random distress is not accepted. Focal Components may show fine wear; supporting and distant Components collapse wear into broader value variation.

## Texture frequency

At 1× reference zoom, no more than three readable texture frequencies may compete on a single Component: primary material grain, secondary wear and one ornament system. Fine noise that disappears under downsampling is omitted.

## Machine data

`data/materials.json` defines roughness, metalness, palette roles, edge behavior and aging guidance for canonical materials.