Как экспортировать OBJ с текстурой (JPG + MTL) из сканирования Arkit LiDAR в iOS? ⇐ IOS

[Anonymous]

Я использую Arkit с RealityKit для сканирования объектов с использованием LiDAR на iOS. Я могу сгенерировать файл OBJ от Armeshanchors, но мне не хватает экспорта текстуры (JPG + MTL). < /P>
Что у меня есть до сих пор: < /p>

• Успешно захватывая сетку с использованием armeshanchor. < /li>
  Преобразование сетки в mdlasset и экспорт .obj. < /li>
  Мне нужна помощь в создании. jpg текстура и связывание ее с файлом .mtl. < /li>
  < /ul>
  private func exportScannedObject() {
  guard
  let camera = arView.session.currentFrame?.camera
  else { return }
  
  func convertToAsset(meshAnchors: [ARMeshAnchor]) -> MDLAsset? {
  guard let device = MTLCreateSystemDefaultDevice() else {return nil}
  
  let asset = MDLAsset()
  
  for anchor in meshAnchors {
  let mdlMesh = anchor.geometry.toMDLMesh(device: device, camera: camera, modelMatrix: anchor.transform)
  
  // Apply a gray material to the mesh
  let material = MDLMaterial(name: "GrayMaterial", scatteringFunction: MDLScatteringFunction())
  material.setProperty(MDLMaterialProperty(name: "baseColor", semantic: .baseColor, float3: SIMD3(0.5, 0.5, 0.5))) // Gray color
  if let submeshes = mdlMesh.submeshes as? [MDLSubmesh] {
  for submesh in submeshes {
  submesh.material = material
  }
  }
  
  asset.add(mdlMesh)
  }
  
  return asset
  }
  
  func export(asset: MDLAsset) throws -> URL {
  let directory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
  let url = directory.appendingPathComponent("scaned.obj")
  
  if MDLAsset.canExportFileExtension("obj") {
  do {
  try asset.export(to: url)
  
  return url
  } catch let error {
  fatalError(error.localizedDescription)
  }
  } else {
  fatalError("Can't export USD")
  }
  }
  
  if let meshAnchors = arView.session.currentFrame?.anchors.compactMap({ $0 as? ARMeshAnchor }),
  let asset = convertToAsset(meshAnchors: meshAnchors) {
  do {
  let url = try export(asset: asset)
  showScanPreview(url)
  } catch {
  print("export error")
  }
  }
  }
  < /code>
  extension ARMeshGeometry {
  func vertex(at index: UInt32) -> SIMD3 {
  assert(vertices.format == MTLVertexFormat.float3, "Expected three floats (twelve bytes) per vertex.")
  let vertexPointer = vertices.buffer.contents().advanced(by: vertices.offset + (vertices.stride * Int(index)))
  let vertex = vertexPointer.assumingMemoryBound(to: SIMD3.self).pointee
  return vertex
  }
  
  // helps from StackOverflow:
  // https://stackoverflow.com/questions/610 ... with-lidar
  func toMDLMesh(device: MTLDevice, camera: ARCamera, modelMatrix: simd_float4x4) -> MDLMesh {
  func convertVertexLocalToWorld() {
  let verticesPointer = vertices.buffer.contents()
  
  for vertexIndex in 0..
  What I Need Help With:
  
  How do I generate the JPG texture from the AR scene?
• How do I save an MTL file linking the OBJ model to the texture?
• How can I correctly apply the texture when viewing the OBJ in an external 3D viewer?

I appreciate any guidance, including sample code or resources!
If you have a complete working solution, I’d love to discuss further via private channels.

Подробнее здесь: https://stackoverflow.com/questions/794 ... can-in-ios