Author Topic: Best way to put opaque paint on transluscent object?  (Read 1055 times)

I want to put opaque paint on a translucent object.

I have been playing around with a translucent object and rendering it in Iray.  Imagine plastic game dice, and I want to put the white dots on them.

In most of my failed attempts, the "paint" is also transparent/translucent.

The thing I've found that seems to work best so far is to make the white dots "Metalic."  But that seems like an odd solution, since in real life the paint is not metal.  Other than that, I've not found a good channel (Transmissive, IOR, etc.) that seems to make the paint opaque.

What am I missing?


P.S.
The attached picture is not mine, but perfectly illustrates what I'm trying to do.
Last Edit: September 11, 2016, 06:31:15 pm
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What is your eventual rendering software?

I know you said "for iray", but I am guessing there is a front end.

I would hazard a guess that you are going to need a mask to block the translucency. How you apply that mask is going to depend on the software.

I know iray some, but most of what I know is from interacting with it through a front end.

My end goal is Iray (from inside Painter).  I'm just playing, learning, and hoping to make pretty pictures.

I messed around with Opacity, and lots of painting on IOR and TRANSMISSION channels, cycling through "channels" to see what they looked like.

My observation so far is that if I paint white or green (or whatever) on top of my yellow plastic, it's still translucent, just a different color.

Painting the "Metal" channel (white) will make it nice and opaque where I paint, but that seems like an odd solution.  Opacity doesn't do it either.

 I did make a nice screwdriver with a plastic handle (complete with refraction and caustics), so I can eventually beat it into submission.  I try to get methodical, but it usually doesn't take long until I'm banging at it more-or-less randomly again, so any actual knowledge you can share will be greatly appreciated.

P.S.
On the Iray "Refraction" settings, next to the Absorption color, do you have any idea what the "A" setting is for (0 to 1)?  It doesn't seem to do anything that I can tell.
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