This is an implementation of the ray-tracer from Jamis Buck's book The Ray Tracer Challenge. It might actually be finished one day.
I'm using it to experiment with and learn more about Kotlin and the Kotest Framework. I do not claim that it is a great example of idiomatic Kotlin, good functional or object-oriented design, efficient coding or anything else. But if you find it interesting or (somehow!) useful, then I'm glad.
By the way, I'm British so would usually spell the (US English) word "color" as (British English) "colour". However, to reduce the cognitive overload in working through the book I found it easier to use "Color" for the class name to better match the test specs. If I didn't I found myself always slightly put off by reading one thing on the page and another in the IDE. But maybe that's just me ...