An SCNNode that draws a circle of given detail

CircleNode.swift

import Foundation
import SceneKit

class CircleNode: SCNNode {
    
    init(detail: Int = 500) {
        
        super.init()

        let elements = self.generateElements(detail: detail)
        let circleSources = self.generateCircleGeometrySources(detail: detail)
        let materials = self.generateMaterials()
        
        let circleGeometry = SCNGeometry(sources: circleSources, elements: elements)
        
        self.geometry = circleGeometry
        self.geometry?.materials = materials
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    private func generateMaterials() -> [SCNMaterial] {

        let material = SCNMaterial()
        material.isDoubleSided = true
        material.lightingModel = .constant
        material.blendMode = .add
        material.diffuse.contents = UIImage(named: "art.scnassets/orbit_gradient.png")
        
        return [material]
    }
    
    private func generateElements(detail: Int) -> [SCNGeometryElement] {
    
        var indices: [Int32] = []
        
        for i in 0..<detail-1 {
            indices.append(Int32(i))
            indices.append(Int32(i+1))
        }
        
        return [SCNGeometryElement(indices: indices, primitiveType: .line)]
    }
    
    private func generateCircleGeometrySources(detail: Int) -> [SCNGeometrySource] {
           
           var verticesVectors = [SCNVector3]()
           var textureCoordsPoints = [CGPoint]()
           
           for i in 0..<detail {
               let per = Float(i) / Float(detail-1)
               let angle = per * (Float.pi * 2)
               
               let vertice = SCNVector3(cos(angle), sin(angle), 0)
               let texture = CGPoint(x: Double(per), y: 0.5)
               
               verticesVectors.append(vertice)
               textureCoordsPoints.append(texture)
           }
           
           let vertices = SCNGeometrySource(vertices: verticesVectors)
           let textureCoords = SCNGeometrySource(textureCoordinates: textureCoordsPoints)
           
           return [vertices, textureCoords]
       }
}

Example use:

var circle = OrbitNode(detail: 1000)
circle.scale = SCNVector3(50, 50, 50)

Hi, how can i change the line width so that it becomes significantly stronger?

@screenworker - this is deliberately generating a circle using primitiveType: .line So it will always be a circle wireframe (which is what I needed). If you want something 'thicker' in a 3D scene then you need to use a geometry that makes sense, a cylinder, or a disk? In the code above where it generates the circle, you could generate points to make a disk instead, and change the primitive type to .triangle.