In the below code I have extracted face mesh vertices from ARKit face anchors and created a custom face mesh using SceneKit SCNGeometry. This enabled me to stretch face mesh vertices as per my requirement. Now the problem I am facing is as follows. I am trying to apply a lipstick texture material which is of type SCNMaterial. Although ARSCNFaceGeometry lets me apply different textures through SCNMaterial and SCNNode, I am not able to do the same using mu CustomFaceGeometry. When I am applying a lipstick texture which looks like the image attached below, the full face is getting colored or modified, I want only that part of the face which has texture transparency as >0 and I dont want other part of the face to be modified. Can you give me a detailed solution using code? // ViewController.swift import UIKit import ARKit import SceneKit import simd class ViewController: UIViewController, ARSCNViewDelegate, ARSessionDelegate{ @IBOutlet weak var sceneView: ARSCNView! let vertexIndicesOfInterest = [250] var customFaceGeometry: CustomFaceGeometry! var scnFaceGeometry: SCNGeometry! private var faceUvGenerator: FaceTextureGenerator! var faceGeometry: ARSCNFaceGeometry! override func viewDidLoad() { super.viewDidLoad() sceneView.delegate = self override func viewWillAppear(_ animated: Bool) { super.viewWillAppear(animated) let configuration = ARFaceTrackingConfiguration() sceneView.session.run(configuration) } } extension ViewController { func renderer(_ renderer: SCNSceneRenderer, didUpdate node: SCNNode, for anchor: ARAnchor) { guard let faceAnchor = anchor as? ARFaceAnchor else { return } customFaceGeometry = CustomFaceGeometry(fromFaceAnchor: faceAnchor) let customGeometryNode = SCNNode(geometry: customFaceGeometry.geometry) customFaceGeometry.geometry.firstMaterial?.fillMode = .lines customFaceGeometry.geometry.firstMaterial?.transparency = 0.0 customFaceGeometry.geometry.firstMaterial?.isDoubleSided = true node.addChildNode(customGeometryNode) } func renderer(_ renderer: SCNSceneRenderer, willUpdate node: SCNNode, for anchor: ARAnchor) { guard let faceAnchor = anchor as? ARFaceAnchor, let faceMeshNode = node.childNodes.first else { return } DispatchQueue.main.async { self.customFaceGeometry.update(withFaceAnchor: faceAnchor, node: faceMeshNode) } } } class CustomFaceGeometry { var geometry: SCNGeometry let lipImage = UIImage(named: "Face.scnassets/lip_arks_y7.png") init(fromFaceAnchor faceAnchor: ARFaceAnchor) { self.geometry = CustomFaceGeometry.createCustomSCNGeometry(from: faceAnchor)! } static func createCustomFaceGeometry(fromVertices vertices_o: [SCNVector3]) -> SCNGeometry { var vertices = vertices_o let vertexData = Data(bytes: vertices, count: vertices.count * MemoryLayout<SCNVector3>.size) let vertexSource = SCNGeometrySource(data: vertexData, semantic: .vertex, vectorCount: vertices.count, usesFloatComponents: true, componentsPerVector: 3, bytesPerComponent: MemoryLayout<Float>.size, dataOffset: 0, dataStride: MemoryLayout<SCNVector3>.stride) let indices: [Int32] = Array(0..<Int32(vertices.count)) let indexData = Data(bytes: indices, count: indices.count * MemoryLayout<Int32>.size) let element = SCNGeometryElement(data: indexData, primitiveType: .point, primitiveCount: vertices.count, bytesPerIndex: MemoryLayout<Int32>.size) return SCNGeometry(sources: [vertexSource], elements: [element]) } static func createGeometry(fromFaceAnchor faceAnchor: ARFaceAnchor) -> SCNGeometry let vertices = faceAnchor.geometry.vertices.map { SCNVector3($0.x, $0.y, $0.z) } return CustomFaceGeometry.createCustomFaceGeometry(fromVertices: vertices) } func update(withFaceAnchor faceAnchor: ARFaceAnchor, node: SCNNode) { if let newGeometry = CustomFaceGeometry.createCustomSCNGeometry(from: faceAnchor) { node.geometry = newGeometry let lipstickNode = SCNNode(geometry: newGeometry) let lipstickTextureMaterial = SCNMaterial() lipstickTextureMaterial.diffuse.contents = lipImage lipstickTextureMaterial.transparency = 1.0 lipstickNode.geometry?.firstMaterial = lipstickTextureMaterial node.geometry?.firstMaterial?.fillMode = .lines node.geometry?.firstMaterial?.transparency = 0.5 } } static func createCustomSCNGeometry(from faceAnchor: ARFaceAnchor) -> SCNGeometry? { let faceGeometry = faceAnchor.geometry var vertices: [SCNVector3] = faceGeometry.vertices.map { SCNVector3($0.x, $0.y, $0.z) } print(vertices[250]) let ll_ratio_y = Float(0.969999) vertices[290] = SCNVector3(x: vertices[290].x, y: vertices[290].y*ll_ratio_y, z: vertices[290].z) vertices[274] = SCNVector3(x: vertices[274].x, y: vertices[274].y*ll_ratio_y, z: vertices[274].z) vertices[265] = SCNVector3(x: vertices[265].x, y: vertices[265].y*ll_ratio_y, z: vertices[265].z) vertices[700] = SCNVector3(x: vertices[700].x, y: vertices[700].y*ll_ratio_y, z: vertices[700].z) vertices[730] = SCNVector3(x: vertices[730].x, y: vertices[730].y*ll_ratio_y, z: vertices[730].z) vertices[25] = SCNVector3(x: vertices[25].x, y: vertices[25].y*ll_ratio_y, z: vertices[25].z) vertices[709] = SCNVector3(x: vertices[709].x, y: vertices[709].y*ll_ratio_y, z: vertices[709].z) vertices[725] = SCNVector3(x: vertices[725].x, y: vertices[725].y*ll_ratio_y, z: vertices[725].z) vertices[710] = SCNVector3(x: vertices[710].x, y: vertices[710].y*ll_ratio_y, z: vertices[710].z) let vertexData = Data(bytes: vertices, count: vertices.count * MemoryLayout<SCNVector3>.size) let vertexSource = SCNGeometrySource(data: vertexData, semantic: .vertex, vectorCount: vertices.count, usesFloatComponents: true, componentsPerVector: 3, bytesPerComponent: MemoryLayout<Float>.size, dataOffset: 0, dataStride: MemoryLayout<SCNVector3>.stride) let indices: [UInt16] = faceGeometry.triangleIndices.map(UInt16.init) let indexData = Data(bytes: indices, count: indices.count * MemoryLayout<UInt16>.size) let element = SCNGeometryElement(data: indexData, primitiveType: .triangles, primitiveCount: indices.count / 3, bytesPerIndex: MemoryLayout<UInt16>.size) return SCNGeometry(sources: [vertexSource], elements: [element]) } }