A NeRF is not the same as an SDF though. NGP (the paper by Nvidia linked here) can train NeRFs and SDFs, but I don't know of any straightforward way of extracti

A NeRF is not the same as an SDF though. NGP (the paper by Nvidia linked here) can train NeRFs and SDFs, but I don't know of any straightforward way of extracting an SDF from a NeRF. And while it's true that there are methods for extracting a surface from a NeRF, achieving a high quality result can be challenging because you have to figure out what to do with regions that have low occupancy (i.e. regions that are translucent). Should you consider those regions as contained within the surface, or outside of it? Especially when dealing with things like hair, it's not obvious how to construct a surface based on a NeRF.