feat(materials): dynamic library registry, picker source tabs, Other category (#525)

* feat(materials): dynamic library registry, picker source tabs, create-material entry point

Core gains a runtime material registry (registerLibraryMaterials/
unregisterLibraryMaterials/subscribeLibraryMaterials) so embedders can
feed user/community materials; library: refs to registered materials
resolve in the viewer unchanged. MaterialCatalogItem carries an optional
source (pascal|community|mine|workspace). MaterialPicker gets a source
filter row and an optional onCreateMaterialRequest '+ New material'
tile, threaded through MaterialPaintPanel.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(materials): underline source tabs in picker, matching catalog browse surfaces

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* feat(materials): add 'other' category for uncategorized library materials

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(viewer): rebuild node material when a texture slot is cleared

Reused cached WebGPU materials keep a compiled TextureNode per slot; nulling
the slot for a cold texture load (or a preset without the map) without
needsUpdate leaves the node's per-frame material reference pulling null,
crashing the render pass in TextureNode.update. Cold loads are the norm for
freshly generated library materials, whose maps aren't in the texture cache.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(viewer): standard materials always carry a displacement texture

three's WebGPU shadow pass copies each object's displacementMap onto one
shared per-light shadow material while caching per-mesh shadow node graphs
against that shared override. A mesh whose shadow graph was built with a
displacement TextureNode (painted with a generated material — the only
presets carrying height maps) crashes the render pass with "null (reading
'matrix')" the moment a material without a displacement texture is swapped
onto it, which is exactly what the paint hover preview does. Give every
MeshStandardNodeMaterial a shared 1x1 black displacement texel (zero offset)
when it has no real height map, so the copied slot is never null in either
direction.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

packages/core/src/index.ts

@@ -157,7 +157,9 @@ export {
 } from './lib/zone-quantities'
 export {
   getCatalogMaterialById,
+  getDynamicLibraryMaterials,
   getLibraryMaterialIdFromRef,
+  getLibraryMaterialsVersion,
   getMaterialPresetByRef,
   getMaterialsForCategory,
   getSceneMaterialIdFromRef,
@@ -168,12 +170,16 @@ export {
   type MaterialCatalogItem,
   type MaterialCategory,
   type MaterialRef,
+  type MaterialSource,
   type MaterialSurface,
   type ParsedMaterialRef,
   parseMaterialRef,
+  registerLibraryMaterials,
   SCENE_MATERIAL_REF_PREFIX,
+  subscribeLibraryMaterials,
   toLibraryMaterialRef,
   toSceneMaterialRef,
+  unregisterLibraryMaterials,
 } from './material-library'
 export type {
   FloorPlacedFootprint,

packages/core/src/material-library.ts

@@ -4,10 +4,14 @@ import {
   MaterialTarget as MaterialTargetSchema,
 } from './schema/material'
 
+export type MaterialSource = 'pascal' | 'community' | 'mine' | 'workspace'
+
 export type MaterialCatalogItem = {
   id: string
   label: string
   category: MaterialCategory
+  /** Origin of the entry. Absent = 'pascal' (all static catalog entries). */
+  source?: MaterialSource
   /**
    * Where this finish is appropriate. Absent = universal (e.g. flat colors).
    * The paint picker may filter by the slot being painted; v1 shows everything.
@@ -69,6 +73,7 @@ export const MATERIAL_CATEGORIES = [
   'roofing',
   'ground',
   'glass',
+  'other',
 ] as const
 export type MaterialCategory = (typeof MATERIAL_CATEGORIES)[number]
 
@@ -4149,13 +4154,64 @@ export const MATERIAL_CATALOG: MaterialCatalogItem[] = [
   },
 ]
 
+const STATIC_CATALOG_IDS = new Set(MATERIAL_CATALOG.map((item) => item.id))
+
+// Embedder-registered library materials (user/community/workspace). Core stays
+// passive: hosts push entries in; nothing here fetches. Static catalog entries
+// win on id collision so a registration can never shadow a built-in.
+const dynamicLibraryMaterials = new Map<string, MaterialCatalogItem>()
+const dynamicLibraryListeners = new Set<() => void>()
+let dynamicLibraryVersion = 0
+
+function notifyDynamicLibraryChange(): void {
+  dynamicLibraryVersion += 1
+  for (const listener of [...dynamicLibraryListeners]) {
+    listener()
+  }
+}
+
+export function registerLibraryMaterials(items: MaterialCatalogItem[]): void {
+  if (items.length === 0) return
+  for (const item of items) {
+    dynamicLibraryMaterials.set(item.id, item)
+  }
+  notifyDynamicLibraryChange()
+}
+
+export function unregisterLibraryMaterials(ids: string[]): void {
+  let changed = false
+  for (const id of ids) {
+    changed = dynamicLibraryMaterials.delete(id) || changed
+  }
+  if (changed) notifyDynamicLibraryChange()
+}
+
+export function getDynamicLibraryMaterials(): MaterialCatalogItem[] {
+  return [...dynamicLibraryMaterials.values()]
+}
+
+export function subscribeLibraryMaterials(listener: () => void): () => void {
+  dynamicLibraryListeners.add(listener)
+  return () => {
+    dynamicLibraryListeners.delete(listener)
+  }
+}
+
+export function getLibraryMaterialsVersion(): number {
+  return dynamicLibraryVersion
+}
+
 export function getMaterialsForCategory(category: MaterialCategory): MaterialCatalogItem[] {
-  return MATERIAL_CATALOG.filter((item) => item.category === category)
+  const items = MATERIAL_CATALOG.filter((item) => item.category === category)
+  for (const item of dynamicLibraryMaterials.values()) {
+    if (item.category === category && !STATIC_CATALOG_IDS.has(item.id)) items.push(item)
+  }
+  return items
 }
 
 export function getCatalogMaterialById(id?: string): MaterialCatalogItem | undefined {
   if (!id) return undefined
-  return MATERIAL_CATALOG.find((item) => item.id === id)
+  return MATERIAL_CATALOG.find((item) => item.id === id) ?? dynamicLibraryMaterials.get(id)
 }
 
 export const LIBRARY_MATERIAL_REF_PREFIX = 'library:'