Going by my experiences trying to make volumetric texturing in Bryce long ago, these queries arise:-

• A volume would seem to need a complete closed box or bag of mesh polygon faces to define that volume.
• Must that bag or box be all within one group (= one prop, or one jointed part of a character)?
• Must that bag or box be all within one material?
• What happens if that bag or box includes any faces with loose edges?
• If I apply volumetric texturing to a whole character, what happens at the joints? Are the joints treated as split face-edges?

In my research volumetrics in Poser is mostly dealing with glass/water caustics and not true volumetrics. I may be wrong here.

You can have volumetric only shaders :) They are not as solid as i would like them to be, but it's possible :)

I have been experimenting with Particles 3 in Poser 11 ... although Snarlygribbly who modified the program into a nifty plug-in for Poser says it doesn't work in PP11, it does have some limited use. AND can work if we can figure out how to diminish the hard edges in the render that is a form of volumetric effects. The plug-in can be found here: http://orphans.basicwiz.com/

Boni - none of those images are volumetric. They're all using transparency to reveal what is behind the particles, but they are completely surface shaders.

SuperFly has true volumetric shading, but not particularly sophisticated. That is where you plug in the Volume shading components. There are three primary volumetric effects offered, which can be combined. They are emission (glow), attenuation, and scatter.

As to Anthony's specific questions about closed volumes, overlapping volumes, etc. I am unable to answer or I would. Simply experiment to see what happens and you'll have an answer. I suggest you start with simple shapes, like a cube missing one side, two overlapping cubes, etc.

Here is what I mean by not sophisticated. Simple situations confuse it. I took a poser box and made it thinner in Z, then duplicated it with overlapping sections.

The result is artifacts at the intersection. Feel free to report all this to SM. My interest in busted rendering continues to decrease.

volume fail.jpg

If I move one box .1 inch so that there are no longer any co-planar faces, the shadow artifact is gone. But the double-density scattering within the intersection is not how you expect a merged volume to work. Like I said - unsophisticated.

SuperFly (Cycles) is not actually "physically based" no matter how many people keep repeating that. It is not simulating the movement of photons one by one. It is using statistical approximations with certain simplifications, and these techniques are going to show flaws if you push them beyond the scenarios they're intended for.

bb, thank you so much for clearing that up ... I was kind of wondering about that with the bothersome edges.