Right out of college, I wrote my first ray tracer in Fortran in the mid-80's at the Xerox Research Centre of Canada. I remember the setup being a VAX 11/750 with a RasterTech color monitor (512x512 if memory serves). [0]

My implementation was based on David Rogers' "Procedural Elements for Computer Graphics", one of only two texts available on 3D graphics, the other being Foley and VanDam.

I remember managing my own stack in a language which didn't support recursion. I learned a lot. Good times.

[0] https://medium.com/@kaveh808/8-summer-at-xerox-in-24-bit-col...