http://sidneys77crlfslcr7zmj3msmxchgnxhrxlp3p3kbaswo7twchjnicid.onion/programming/2022/03/23/raytracing.html
To remedy this, we’ll add the concept of Fog. We already have a Fog color, for when a ray doesn’t hit anything. This new
concept applies the idea of there being some extreme translucency to the nothingness between a ray’s origin and the Shape it intersects with.