Oh hey, that was also the topic of my master's thesis. In particular doing it for arbitrarily large scenes without running out of memory.

https://www.cg.tuwien.ac.at/research/publications/2015/WEBER...

Code here: https://github.com/ginkgo/micropolis (I guess it's gotten a bit bit-rotten at this point)

Title should be marked with [2015]. I was caught off-guard with the statement about RenderMan using REYES since it hasn’t used it for several years at this point.

There are quite a few interesting publications to look through, need to bookmark this: https://markussteinberger.net/publications.php