"Opacity Maps" in iray?
Scavenger
Posts: 2,674
I'm converting an old verhicle model to IRAY. I'm using some paint shaders for most of it, and they work just fine.
BUT, I want to have some decals on the surface. I have them on a diffuse map, surrounded by white, and that works like I thought, with the white areas giving the paint shader color unaltered. Howver, the paint color also goes thru the decal. In 3Delight I'd use an opacity map, but that's not a thing in IRAY. (I know that cutout opacity actually takes out the polygons, not the maps).
I'm looking at Sickle Yield's post on what the differen't things mean, but I' can't figure out what to use...
http://sickleyield.deviantart.com/journal/Iray-Surfaces-And-What-They-Mean-519346747
Is this a) possible, b) how's it done? c) does it use the white/black maps?

Comments
I think what you're looking for is a "Decal".
Check:
http://www.daz3d.com/forums/post/quote/57322/Discussion_57322
and for the opacity part:
http://www.daz3d.com/forums/post/quote/58456/Discussion_58456
I'd use the LIE personally. It works fine in Iray.
Links should be:
http://www.daz3d.com/forums/discussion/57322/
http://www.daz3d.com/forums/discussion/58456/
Iray's decal feature is really meant for automating text or art into commercial product renders -- language localization, and such. The decal can be applied to scene data without manual steps. I'm glad Daz exposed the interface, but I'm not sure other methods aren't easier and more productive. Does it not work to add it as an input to one of the top layers?
Wait, so clothes with opacity maps in their surfaces will no longer work with iray? Are decals really the only way to do this?
No, clothes with opacity maps use the Cutout Opacity to hide the unwanted areas. I'm not really understanding what is different between Iray and 3Delight here.
I *think* that the difference is this:
In 3delight, the 0% opacity sections were still there, as physical objects, but just invisible. I had this bite me using AOA lights, where a ripped shirt had the ripped-off parts be invisible, but still cast shadows.
In Iray, the 0% cutout sections are not treated as physical objects. So they neither render nor generate shadows.
I suspect from an end-user perspective, 99% of the time, the difference between these is not noticeable.
Basic question...what format are the maps? (tif, jpg, png)
Opacity maps? I think you can use any of the ones you listed.
Jpg and PNG.
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I'm thinking what I want is not possible.
using this map, only the logo was there, and the rest of the geometry is erased.
I assume the inverse of the mask will put a hole whrer the logo is, rather than just isolate it from the other effects. (because of iray, daz now crashes when opened, so I need to restart before it'll work again)
In Photoshop, it'd just be on a layer above the layer,
I could do what i want by duplicating the bike, putting my maps on it, including the cutout, and cutting everything else and have it parented to the first bike just a tiny bit above.
There should be an easier way.
Probably going to have to use the LIE (Layered Image Editor)....or similar to the 'duplicate' idea...use a GeometryShell.
Another way is to use Photoshop and make a diffuse map for each color you want.
Post reboot.. I'm trying the my dupe idea...it works....
Some weirdness, rendering just the logos on the 2nd bike (the pic below) takes longer and the computer works harder, than rendering the first bike, with nothing hidden....which points to CutOuts causes more calculations and slowness?
Also, some parts that are cut out, still show up in viewport, but they don't render. That's weird.
i've not used a Geometry Shell before..I've heard of it...I guess I'll go a-googling.
I'm rather good with photoshop...I don't think I could make diffuse textures that look as good, not by half.
Wow.
Well. for once, something was obvious and instinctual.
Did Daz hire an Apple programer to design geometry shells?