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nycL45
11-08-2005, 10:52 PM
It is probably not practical to create perforated brushed stainless steel sheet with 1cm[5/16"] dia. holes at 2cm[3/4"] o.c. Imagine at least 1000 holes! In my case, the material acts like a screen and this and that will be visible through it and the brushed texture will be visible. So, what is a good method to simulate this material or an alternative? This is for an exhibit case and I would like to include a fairly close view.

Per-Anders
11-08-2005, 11:00 PM
well one way would be to use the tiles shader in alpha and in bump. it's somewhat limited though. or a hand painted texture, to make it slightly more convincing you could apply it to two or three layers of mesh planes on top of one another so that it has more of a look of some thickness from a distance.

really if you are going to get close i would consider modeling at least a small section of perforated screen, after all you could simply do it by making a plane, inner extruding all polygons on the surface with keep groups off a couple of times, delete the polygon holes, extrude the whole mesh with caps on, and putting the result in a hypernurbs mesh, then if you want you could finally make that mesh editable and use the polygon reduction tool to simplyfy the resulting mesh somewhat... the result would be messy then but it shouldn't show in render.

Primitiv
11-08-2005, 11:28 PM
Using an alpha is the most economical way for 1000 holes. Depending on where you would get the closest, you could make 1 hole using a boolean object and instance it many times for rendering.

Ernest Burden
11-09-2005, 02:05 AM
So, what is a good method to simulate this material or an alternative? This is for an exhibit case and I would like to include a fairly close view.

I have that task on my list for today, as it happens. I've always used a TARGA file for that (for its alpha channel). Pretty quick, simple, work perfectly.

If you will be close the you should:
1. use a high-res map for the hole (you only need one), something that will be a little more than the maximum number of pixels when you see it the closest, and
2. give the metal poly object a thickness, simple extrude it inward by some small amount. For extra credit you could make the backside (inside) of the two poly surfaces have a slightly darker material, but that's not necessary.

To extrude an inner shell you can use 'extrude inner' to pull a new set of polys smaller than the original (they will stay planar), then scale them back to the same size (they stay selected as you work), visually is fine, then 'normal move' to get the new surf just inside the original one.

edit: oh, the final step is to reverse the normals of the new inner skins, and this all assumes you started with correct normals. Have a nice day.

PhillipCrond
11-09-2005, 05:19 AM
I actually replied to a topic about this a loooong time ago, and this is what I said:

http://www.thesecretmission.com/cgtalk/grill1.jpg

Just a reflective shader with a repeating bump and alpha map:
BUMP:
http://www.thesecretmission.com/cgtalk/grill_bump.jpg

ALPHA:
http://www.thesecretmission.com/cgtalk/grill_alpha.jpg

nycL45
11-09-2005, 12:30 PM
Thanks all. The panel is triangular and both the alpha, for distant view, and modeling a section for the closeup are the way to go.

"... and this is what I said:" Brent, nicely said (your technique).

nycL45
11-09-2005, 02:55 PM
Brent or others, how does one create the even gray shading around the Bump material holes and duplicate it to the other holes?

Ernest Burden
11-09-2005, 03:37 PM
Brent or others, how does one create the even gray shading around the Bump material holes and duplicate it to the other holes?

Just did this five minutes ago...gausian blur in Photoshop

Now for the AA nightmare of actually rendering all those little holes.

nycL45
11-09-2005, 04:33 PM
Who would have thunk. Thx. Good luck with your little friends. :arteest:

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