It seems like blender does not have a feature to render light path expressions like these in RenderMan.
There's a thread on devtalk about this but I havent seen any further updates.
Essentially, I want to render the LPEs found in the Stylit paper (see figure 4).
Here's a screenshot of it : https://imgur.com/a/9K3lsL1.
full global illumination render
direct diffuse render
direct specular render
first two diffuse bounces
and diffuse inter-reflections.
The first is straightforward but trying to generate the others using blender's cycle renderer is not trivial. I've managed to generate 2 and 3 (here: https://i.imgur.com/2BItEsz.png) but I can't seem to render no. 5.
Is there a better way to go about this in blender? Or are there open source libraries that are probably more fitted for this?