Opacity map on thick material

[Sid Hatrack]

This is my first go round with opacity maps and I am wondering if they do not work so well on thick geometry. Here I am trying to give the appearance of perforated ceramic insulation blocks which are about 2 inches thick. I am using this black and white image as a map but the holes do not look right to me. It looks like the holes are on a thin surface with another surface below it.

[TGS808]

What you're doing is ideal for adding small grills and other perforated parts that maybe won't be front and center in your model or will be seen from a distance. Doing it like this will avoid having to model hundred of little holes. However, if you want it to punch holes but maintain some thickness (that is, not look like a flat, 2D screen), using an opacity map won't work.

Side note:
If you are going to use an opacity map like the one in your example in the future for any reason I'd recommend using KeyShot's built in procedural mesh texture. Doing that allows you a lot of interactive control over the size, shape, and spacing of the pattern. Try it and you'll find it's a much better option than the static, fixed resolution JPEG you are using.

[DMerz III]

Yes - essentially your shape is made of 'surfaces' not actually a thick block, because most of the time, we will never need to worry about what's behind the skin of an object, therefore, it's best to not waste a computer's resources to account for what we 'don't see'.

In your case - you're going to want to actually model in those surfaces.