model tree

src/client/viewer/main.ts

@@ -2,7 +2,7 @@ import '../style.css'
 import * as THREE from 'three'
 import { OrbitControls } from 'three/addons/controls/OrbitControls.js'
 import { STLLoader } from 'three/addons/loaders/STLLoader.js'
-import type { GeometryFile } from '../../server/services/stepConverter'
+import type { GeometryFile, HierarchyNode } from '../../server/services/stepConverter'
 
 // ---- Data injected by viewer.ejs -----------------------------------------
 
@@ -22,6 +22,9 @@ let camera:      THREE.PerspectiveCamera
 let controls:    OrbitControls
 let viewingDist: number = 200  // updated by fitCamera; used by fog toggle
 
+// Map from geometry-JSON mesh index → Three.js Mesh, used by the tree panel
+const meshObjects = new Map<number, THREE.Mesh>()
+
 // ---- UI helpers ----------------------------------------------------------
 
 function setLoading(msg: string) {
@@ -244,7 +247,8 @@ async function loadStepGeometry(): Promise<void> {
   const group = new THREE.Group()
   const isV2  = data.version >= 2
 
-  for (const mesh of data.meshes) {
+  for (let i = 0; i < data.meshes.length; i++) {
+    const mesh = data.meshes[i]
     const geo = new THREE.BufferGeometry()
 
     let positions: Float32Array
@@ -273,12 +277,16 @@ async function loadStepGeometry(): Promise<void> {
       geo.computeVertexNormals()
     }
 
-    group.add(new THREE.Mesh(geo, makeMaterial(mesh.color)))
+    const threeMesh = new THREE.Mesh(geo, makeMaterial(mesh.color))
+    meshObjects.set(i, threeMesh)
+    group.add(threeMesh)
   }
 
   scene.add(group)
   fitCamera(group)
   addGrid(group)
+
+  if (data.tree) wireTreePanel(data.tree)
 }
 
 // ---- STL loader (client-side, Three.js built-in) -------------------------
@@ -318,6 +326,109 @@ async function loadStl(): Promise<void> {
   addGrid(mesh)
 }
 
+// ---- Model tree ----------------------------------------------------------
+
+function setNodeVisible(node: HierarchyNode, visible: boolean) {
+  for (const idx of node.meshes) {
+    const m = meshObjects.get(idx)
+    if (m) m.visible = visible
+  }
+  for (const child of node.children) setNodeVisible(child, visible)
+}
+
+function buildTreeNode(node: HierarchyNode, depth: number): HTMLElement {
+  const label       = node.name.trim() || 'Solid'
+  const hasChildren = node.children.length > 0
+
+  const wrapper = document.createElement('div')
+
+  const row = document.createElement('div')
+  row.className = 'flex items-center gap-1 py-1 rounded-lg hover:bg-white/5 group select-none'
+  row.style.paddingLeft = `${6 + depth * 14}px`
+  row.style.paddingRight = '6px'
+
+  // Chevron
+  const chevron = document.createElement('span')
+  chevron.className = `w-3.5 h-3.5 shrink-0 text-gray-600 transition-transform duration-150 ${hasChildren ? 'cursor-pointer' : 'invisible'}`
+  chevron.innerHTML = `<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><path stroke-linecap="round" stroke-linejoin="round" d="M9 5l7 7-7 7"/></svg>`
+
+  // Eye toggle
+  const EYE_ON  = `<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.75"><path stroke-linecap="round" stroke-linejoin="round" d="M2.036 12.322a1.012 1.012 0 010-.639C3.423 7.51 7.36 4.5 12 4.5c4.638 0 8.573 3.007 9.963 7.178.07.207.07.431 0 .639C20.577 16.49 16.64 19.5 12 19.5c-4.638 0-8.573-3.007-9.963-7.178z"/><path stroke-linecap="round" stroke-linejoin="round" d="M15 12a3 3 0 11-6 0 3 3 0 016 0z"/></svg>`
+  const EYE_OFF = `<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.75"><path stroke-linecap="round" stroke-linejoin="round" d="M3.98 8.223A10.477 10.477 0 001.934 12C3.226 16.338 7.244 19.5 12 19.5c.993 0 1.953-.138 2.863-.395M6.228 6.228A10.45 10.45 0 0112 4.5c4.756 0 8.773 3.162 10.065 7.498a10.523 10.523 0 01-4.293 5.774M6.228 6.228L3 3m3.228 3.228l3.65 3.65m7.894 7.894L21 21m-3.228-3.228l-3.65-3.65m0 0a3 3 0 10-4.243-4.243m4.242 4.242L9.88 9.88"/></svg>`
+
+  const eyeBtn = document.createElement('button')
+  eyeBtn.className = 'w-3.5 h-3.5 shrink-0 text-gray-500 hover:text-white transition-colors opacity-0 group-hover:opacity-100'
+  eyeBtn.title = 'Toggle visibility'
+  eyeBtn.innerHTML = EYE_ON
+
+  let visible = true
+  eyeBtn.addEventListener('click', (e) => {
+    e.stopPropagation()
+    visible = !visible
+    eyeBtn.innerHTML        = visible ? EYE_ON : EYE_OFF
+    eyeBtn.style.opacity    = visible ? '' : '1'
+    eyeBtn.style.color      = visible ? '' : 'rgb(248 113 113)'
+    nameEl.style.opacity    = visible ? '' : '0.3'
+    setNodeVisible(node, visible)
+  })
+
+  // Name
+  const nameEl = document.createElement('span')
+  nameEl.className = 'text-xs text-gray-300 truncate flex-1'
+  nameEl.textContent = label
+
+  row.append(chevron, eyeBtn, nameEl)
+  wrapper.append(row)
+
+  if (hasChildren) {
+    const childrenEl = document.createElement('div')
+    for (const child of node.children) {
+      childrenEl.append(buildTreeNode(child, depth + 1))
+    }
+
+    let expanded = true
+    chevron.style.transform = 'rotate(90deg)'
+
+    const toggle = () => {
+      expanded = !expanded
+      chevron.style.transform      = expanded ? 'rotate(90deg)' : ''
+      childrenEl.style.display     = expanded ? '' : 'none'
+    }
+
+    chevron.addEventListener('click', (e) => { e.stopPropagation(); toggle() })
+    row.addEventListener('click', toggle)
+    wrapper.append(childrenEl)
+  }
+
+  return wrapper
+}
+
+function wireTreePanel(root: HierarchyNode) {
+  const content = document.getElementById('tree-content')
+  if (!content) return
+
+  // Skip an unnamed single-child root wrapper — go straight to its children
+  const topNodes = (!root.name && root.children.length > 0) ? root.children : [root]
+
+  content.innerHTML = ''
+  for (const node of topNodes) {
+    content.append(buildTreeNode(node, 0))
+  }
+
+  // Wire tree toggle button
+  const treePanel  = document.getElementById('tree-panel')!
+  const toggleBtn  = document.getElementById('tree-toggle-btn')
+  const closeBtn   = document.getElementById('tree-close-btn')
+
+  const openPanel  = () => { treePanel.classList.remove('closed'); toggleBtn?.classList.add('text-accent') }
+  const closePanel = () => { treePanel.classList.add('closed');    toggleBtn?.classList.remove('text-accent') }
+
+  toggleBtn?.addEventListener('click', () =>
+    treePanel.classList.contains('closed') ? openPanel() : closePanel()
+  )
+  closeBtn?.addEventListener('click', closePanel)
+}
+
 // ---- Viewer toolbar ------------------------------------------------------
 
 function wireToolbar() {

src/server/services/stepConverter.ts

@@ -3,17 +3,25 @@ import fs from 'fs'
 import path from 'path'
 
 export interface GeometryMesh {
+  name:      string
   positions: string              // base64-encoded Float32Array
   normals:   string | null       // base64-encoded Float32Array
   indices:   string              // base64-encoded Uint32Array
   color:     [number, number, number] | null
 }
 
+export interface HierarchyNode {
+  name:     string
+  meshes:   number[]             // indices into GeometryFile.meshes
+  children: HierarchyNode[]
+}
+
 export interface GeometryFile {
   version:    2
   sourceFile: string
   meshCount:  number
   meshes:     GeometryMesh[]
+  tree?:      HierarchyNode      // absent on files converted before tree support
 }
 
 // Singleton — WASM initializes once per Node process (~3 s on first call, instant after)
@@ -59,12 +67,14 @@ export async function convertStepFile(
       const nor = mesh.attributes.normal ? new Float32Array(mesh.attributes.normal.array) : null
       const idx = new Uint32Array(mesh.index.array)
       return {
+        name:      mesh.name ?? '',
         positions: Buffer.from(pos.buffer, pos.byteOffset, pos.byteLength).toString('base64'),
         normals:   nor ? Buffer.from(nor.buffer, nor.byteOffset, nor.byteLength).toString('base64') : null,
         indices:   Buffer.from(idx.buffer, idx.byteOffset, idx.byteLength).toString('base64'),
         color:     mesh.color ? [mesh.color[0], mesh.color[1], mesh.color[2]] : null,
       }
     }),
+    tree: result.root,
   }
 
   fs.writeFileSync(outputPath, JSON.stringify(geo))

src/server/types/occt-import-js.d.ts

@@ -4,12 +4,19 @@ declare module 'occt-import-js' {
     normal?:  { array: Float32Array }
   }
   interface OcctMesh {
+    name:       string
     attributes: MeshAttributes
     index:      { array: Uint32Array }
     color:      number[] | null
   }
+  interface HierarchyNode {
+    name:     string
+    meshes:   number[]          // indices into ReadResult.meshes
+    children: HierarchyNode[]
+  }
   interface ReadResult {
     success: boolean
+    root:    HierarchyNode
     meshes:  OcctMesh[]
   }
   interface OcctModule {

views/viewer.ejs

@@ -5,6 +5,8 @@
   #viewer-canvas { display: block; width: 100vw; height: 100vh; }
   #pdf-panel  { transition: transform 0.3s ease; }
   #pdf-panel.closed  { transform: translateX(100%); }
+  #tree-panel { transition: transform 0.3s ease; }
+  #tree-panel.closed { transform: translateX(-100%); }
 </style>
 
 <!-- 3D Canvas -->
@@ -32,6 +34,16 @@
 <!-- Top-right controls -->
 <div class="fixed top-5 right-5 flex items-center gap-2 z-20">
 
+  <!-- Model tree toggle (STEP/STP only) -->
+  <% if (model.file_type === 'step' || model.file_type === 'stp') { %>
+  <button id="tree-toggle-btn" title="Toggle model tree"
+    class="flex items-center justify-center w-10 h-10 md:w-8 md:h-8 bg-surface-900/90 backdrop-blur-sm border border-gray-700 hover:border-gray-600 text-gray-400 hover:text-white rounded-xl transition-all">
+    <svg class="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="1.75">
+      <path stroke-linecap="round" stroke-linejoin="round" d="M8.25 6.75h12M8.25 12h12m-12 5.25h12M3.75 6.75h.007v.008H3.75V6.75zm.375 0a.375.375 0 11-.75 0 .375.375 0 01.75 0zM3.75 12h.007v.008H3.75V12zm.375 0a.375.375 0 11-.75 0 .375.375 0 01.75 0zm-.375 5.25h.007v.008H3.75v-.008zm.375 0a.375.375 0 11-.75 0 .375.375 0 01.75 0z"/>
+    </svg>
+  </button>
+  <% } %>
+
   <!-- Fog toggle -->
   <button id="fog-btn" title="Toggle atmosphere fog"
     class="flex items-center justify-center w-10 h-10 md:w-8 md:h-8 bg-surface-900/90 backdrop-blur-sm border border-gray-700 hover:border-gray-600 text-gray-400 hover:text-white rounded-xl transition-all">
@@ -98,6 +110,23 @@
   <p class="text-xs text-gray-700 md:hidden">1 finger — rotate &nbsp;·&nbsp; 2 fingers — pan/zoom</p>
 </div>
 
+<!-- Model tree panel (left side, STEP/STP only) -->
+<% if (model.file_type === 'step' || model.file_type === 'stp') { %>
+<div id="tree-panel" class="fixed top-0 left-0 h-full w-64 bg-surface-900/95 backdrop-blur-sm border-r border-gray-800 z-20 closed flex flex-col">
+  <div class="flex items-center justify-between px-4 py-4 border-b border-gray-800 shrink-0">
+    <h2 class="text-sm font-semibold text-white">Model Tree</h2>
+    <button id="tree-close-btn" class="p-1.5 rounded-lg text-gray-500 hover:text-white hover:bg-surface-800 transition-colors">
+      <svg class="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="2">
+        <path stroke-linecap="round" stroke-linejoin="round" d="M6 18L18 6M6 6l12 12"/>
+      </svg>
+    </button>
+  </div>
+  <div id="tree-content" class="flex-1 overflow-y-auto py-2">
+    <p class="text-xs text-gray-600 px-4 py-2">Awaiting model load…</p>
+  </div>
+</div>
+<% } %>
+
 <!-- PDF slide-in panel -->
 <% if (pdfs.length > 0) { %>
 <div id="pdf-panel" class="fixed top-0 right-0 h-full w-full max-w-md bg-surface-900 border-l border-gray-800 z-20 closed flex flex-col">