@Miss Nancy: looks fine, thank you. Since refract and reflect can't deal with direct light, we will never have caustics or volumetric coloring this way. But just having somewhat believable shadows is something at least.

@BB: thanks for the reply.

#Blinn: I just wondered what your arguments were. I could have run a forum search instead, you're pretty consistent on this for some years now. Sorry.

#Reflection: running some testrenders right now. My current theory (to be tested) is: like refraction, reflection ignores transparency as well. So when light from an object (A) hits a surface at the front of object (B) then part R will be reflected while part T will be transmitted at the same time (and Poser is quite happy to do both at 100%).

Then that reflected part will be reflected again at the back of B, and passes the surface at the front while being reduced by transparency T again. And also, it will bounce back at the backside of the front and so on and on.

As a result, the output at the front of B will be R( 1+ T^2 /(1- R^2) ).

When I do the output at the back the same way, and demand that together they remain <100%, then R^2 < (1- T^2) to stay within physical limits.

But actually one would expect R = r (1-T) as r is the reflectivity 0..100% for the non-transparent part, as the transparent portion of the surface should not reflect at all. As in: when the surface lets 50% of the light pass, it can't reflect more than the other 50%. But one should set that oneself, Poser is not doing it.

Let's see what the tests bring us. Combining partial transparency with reflection is a real rendertime killer. In the meantime, I'm open to alternative theories.

- - - - - 

Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though