Developer Forum

Shader AOV For Volumens

I’m trying to use Shader AOV to cast an output in a Principaled Volume, but I think Shader AOV doesn’t work with volumes.

Is this correct, do you plan to make it work in the future? It would be VERY USEFUL, for example, to generate more detail in explosions.

How should the effect for surfaces work in volume? Do you want to know the average / nearest / soft distance to the nearest surface / set of surfaces / including reflections? why?

Imagine I want to add a glow to an explosion. But I want to use Temperature to add fire to the explosion, and Heat or Flame to add another color of fire. I would want to have those 2 channels (temperature and flame) separately, to add different glow effects in the compositor.

Being able to have in separate outputs the channels of a volume (density, temperature, flame, heat) would be very useful for the composer.

Oh, sorry, I took it as a term for AO from the very beginning. Yes, blender has AOV, so I’m not sure what you mean.
But I still don’t see much in how volume masks can be used, but I’ll see that later from the discussion here…

just as if you activate the emission pass, from the compositor you can add a glow, I would like to be able to do the same, but separating flame, temperature, heat… and be able to work with those channels separately from the compositor.

The problem in my understanding is that you either have colors (which can be mixed) or masks (if you have a mask of red and blue and purple to consider these as certain types of objects, then you obviously will not like it if from red and blue fog will appear the third kind of textures…)