Mental Ray Glass

Today’s write-up is simple. Just glass. MR makes it very easy to create realistic glass with the A&D shader. I start with a fresh A&D shader, and all I change is the reflection to 1.0 and the refraction to 1.0….that’s it! Here’s what it looks like:

Color in the refraction is a light green

Note that to get glass to work like the image above, the glass must be a solid (there's a thickness to the glass). If you were to render the same glass above onto a thin plane this is what it would look like:

Notice that the refraction color gets lost

Obviously this image is incorrect and defies much of physics. The question is how do you create glass with a plane? You have to change the Advanced Transparency Options from "Solid" to "Thin-walled". Now when the thin plane renders it looks like this:

This is a great solution for thin planes, but the only way to achieve truly realistic glass is by giving it a thickness (think about the shell modifier).