Simple ray-tracing renderer written in Swift, based on the book The Ray Tracer Challenge by Jamis Buck. I highly recommend this book!
Contains implementations until the end of Chapter 8 of the book on shadows.
SwiftRayTracer - The renderer written as a Swift package
Swiftracer-macOS - macOS app using the renderer package to render a simple scene
All you need to do is open Swiftracer-macOS/Swiftracer-macOS.xcodeproj and run. Xcode will automatically load the SwiftRayTracer package's code alongside the project.