[wass08]

What does this PR do?

Lets author_scene and the MCP tools build more faithful finishes:

• Columns in author_scene take code (the add_column module contract, mount floor), rotation, and a color that is now applied, as an exact material on every native surface (it was stored in metadata and never applied).
• Same gap on other kinds: a slab's railing accepted a height but the slab renderer drew every run at 1.1 m in the slab's edge finish. Slab railings are now fences standing on the slab (supportSlabId) with their own height and a new color. Stairs now take railing (sides), railingStyle, color (flight), treads and railingColor.
• exact: true on paint (with color: that colour as a matte scene material, not the nearest library colour) and on add_object (the module's slot colours with their roughness/metalness, not their library matches; glass and emissive slots keep theirs). One shared helper (exactColorMaterial / exactScriptSlots) now backs author_scene's exact slots too.
• Native textures take offset, normalMap/normalScale, bumpMap/bumpScale; the viewer applies them (maps share the albedo's repeat and offset; normal/bump are non-colour, rendered shading only). New map URLs are inventoried as asset references; reference discovery now treats any AssetUrl field as a reference. paint documents the UV convention so an agent can line joints up (offset = frac(−c × repeat)).
• Slab surface scripts: a standalone slab (not a room's floor plate, boundary !== 'auto') can carry surfaceScript, the same record as a room's floor.script: author_scene surfaceCode, setSlabSurfaceScript, refreshed by refreshFinishScripts when reshaped, drawn on the slab's top, owning the surface's colours (paint refused), items stand on its build, get_source reads it, clipboard carries its artifacts, the slab panel shows it (view / remove, like the room panel, via a shared ScriptedFinishRow).

Reviewer note: the slab kind now has a lazily loaded renderer (ParametricNodeRenderer + the script build beside the slab's group), like columns, doors and ceilings, instead of the default generic mount. ParametricNodeRenderer is exported from viewer for that.

Old scenes load unchanged: every new field is optional.

How to test

1. bun run ci (run locally: green).
2. author_scene a payload with a slab { polygon, top: 0.3, surfaceCode: <decking module> } and a column with code and another with color: the slab shows the decking on its top, the coded column its module, the coloured one that exact colour on shaft/base/capital.
3. paint a wall with { color: '#3a5f8c', exact: true }: a scene material named #3a5f8c is created and reused on a second call.
4. paint a floor with a native material { texture: { url, repeat: [2, 2], offset: [0.5, 0], normalMap } }: the pattern shifts half a tile and shows relief.

Screenshots / screen recording

Checked locally in apps/editor (next dev): a payload sent through the MCP author_scene tool, with real compiles and the app's artifact store, then a textured paint. It renders the terrace's script-built decking on the slab top, cut to its outline; a 0.9 m red railing standing on it; a native column in its exact green, turned 30°; a scripted post in its module's exact blue; and a brick wall face with its normal map, offset half a tile. The slab kind's new renderer path also renders an existing project's slabs unchanged. No new console errors; the two "synchronously unmount a root" warnings also show without this change. No recording attached.

Checklist

• I've tested this locally with bun dev
• My code follows the existing code style (run bun check to verify)
• I've updated relevant documentation (if applicable)
• This PR targets the main branch

🤖 Generated with Claude Code

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Note

Medium Risk
Broad changes to agent paint/add_object, author_scene placement, finish-script refresh, and spatial elevation, but new schema fields are optional and heavily tested.

Overview
Adds exact: true on paint and add_object so hex colours become reusable scene materials instead of nearest library matches; scripted slots keep authored roughness/metalness while glass and emissive slots stay special. Shared exactColorMaterial / exactScriptSlots also drive author_scene exact slot mapping.

Native materials gain texture offset, normalMap/normalScale, and bumpMap/bumpScale (viewer applies shared placement; paint documents UV/joint alignment). Reference inventory and discovery cover the new map URLs.

Standalone slabs (not room floor plates) can carry surfaceScript via setSlabSurfaceScript and author_scene surfaceCode: compile on outline, refresh when reshaped, refuse surface paint, elevate placed items on the build, get_source / clipboard / slab panel parity with room floor scripts; slab kind gets a composed renderer.

author_scene also wires slab railings as height/coloured fences on the slab, columns with code, rotation, and applied color, and stairs with railing mode/style and body/tread/railing finishes.

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Cursor Bugbot has reviewed your changes using high effort and found 2 potential issues.

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[cursor]

Slab railings decouple from the slab

Medium Severity

Slab railing runs are now separate level-parented fences linked only by supportSlabId. Deleting, duplicating, or translating the slab no longer takes those railings with it, so a balcony can vanish while its rails drop to the floor or stay behind in plan.

Additional Locations (1)

• packages/nodes/src/slab/definition.ts#L346-L350

 

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[cursor]

Script height skipped for slab hosts

Medium Severity

A slab surfaceScript raises the walking surface in floorFinishTopAt, but surfaces.top still returns the structural elevation and fence supportSlabId lift does too. Railings and anything hosted through that surface sit inside the decking instead of on it.

Additional Locations (1)

• packages/core/src/lib/floor-script.ts#L74-L81

 

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