Build an offline ray tracer for UE4 - where to start?

Hey, UE4 Experts –

I have experience writing ray tracers, but not in UE4.

I’m working on my own implementation of ray tracing/ray marching/denoising. I can’t use the built-in real-time ray tracer, and I’m looking to find out where I would begin to understand where in UE4 I would look to make this integration (plugin? module? fork the repo?). Also, I’m aware of plugins like V-Ray, but I am working with some unique/odd use cases and need to be able to call my own code and have full control over the process. Customizing the existing material functions, properties in UE4 also won’t work for my use case.

I’ve been going through some of the documentation, but am unclear the best way to approach this and where to start. If I were making a new variant of V-Ray, where should I begin to look for integration points?

Any guidance or tips in terms of where I should start looking would be greatly appreciated. Thank you in advance!