I did something similar here: https://blog.habets.se/2015/03/Raytracing-Quake-demos.html [2015]

The author's write-up is better, and his target (Blender) enables some things mine (POV-Ray) doesn't.

I also really like the idea to use emissive textures. I just used point light sources.

I'm still rendering, and you can join if you want: https://qpov.retrofitta.se/