Windows and doors build all visuals in their viewer systems from module-global
materials, so this threads per-node slot materials + userData.slotId tags
through those builders without restructuring them:
- window: 'frame' + 'glass' slots. door: 'panel' (body = casing + leaf) +
'glass'; the opening reveal keeps its own material.
- Each system captures per-frame viewer state, then updateWindow/DoorMesh points
the builder-facing base/glass materials at the node's resolved slot override
(recomputed per node, so the next node resets without a restore). Meshes are
auto-tagged in the shared addBox/addShape helpers by which material they got.
- Textures-off still collapses to the role material (escape hatch); a slot
override only applies in colored mode.
- Editing a referenced scene material re-dirties the window/door (these systems
aren't covered by GeometrySystem's scene-material re-dirty).
- New paint capabilities (resolve role from userData.slotId, preview by
userData.slotId) + capabilities.slots; window/door dropped from the paint
disabled list. Shared previewSlotByUserData helper.
Defaults unchanged: unpainted windows/doors render exactly as before (the slot
fallback is the existing frame/glass material), so no visual regression.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>