Render AOV correctly for an texture on a plane with an alpha (cutout opacity)?

[mdouglas66J8T]

Hi there, I have multiple objects that are just textures on planes. Some are single objects, others are C4D cloners. They have an alpha to cut out the texture properly (attached to Cutout opacity < Geometry < Main). They render fine in the beauty pass, but when I render AOVs of them, I just get the entire plane. Is there a fix for this? AOVs for objects behind them cut out the object correctly (eg: the sky). I added the Arnold Parameters tag and unchecked Opaque just in case, but that did nothing.

Also, unrelated question - if I add a color correct node, the material preview in the viewport goes black. Is there a fix for this? Thanks!

[Dominik_Source1]

Unfortunatly I don't have an answer for your problem, but I have experienced the same issue with the color correct node. Would be interested in a fix as well.

[peter.horvath6V6K3]

When you say "render AOVs of them", do you mean an object mask tag? You can use an aov_write_float shader instead and connect the same opacity texture to its AOV input.

About the color_correct viewport issue, is that in the old node editor or in the new Node Material?

[mdouglas66J8T]

Thanks Peter! Ok, that's good to know. Yes I meant the object mask tag. I'm pretty new to Arnold so I wasn't aware of that, and I'm not sure how to set that up. Can it be set that up so it will render all in one pass? (so it looks correct in the beauty pass and also generates the alpha). Would you be able to step me through how I'd do that? I can connect the image node with the alpha to the input, but I'm not sure what to do with the output. Much appreciated.

Re: the color correct issue, yes I'm using the node editor. I'm not sure what you mean about node materials. (again, I'm kind of a noob) See attached screenshot.

Thx very much!

color correct node.jpg

[peter.horvath6V6K3 · Accepted solution]

This is what I was thinking of, writing the opacity texture to a custom AOV. Connect the texture to the 'AOV Input' and the surface shader to the 'Passthrough'.

I could reproduce the viewport issue with the color_correct shader, I'll work on a fix.

The Node Material is the new native node-based material system in recent Cinema 4D versions, which is supported since C4DtoA 4.0: https://docs.arnoldrenderer.com/pages/viewpage.action?pageId=149225944

[mdouglas66J8T]

Amazing! Thanks so much Peter. I'll try that out.

[mdouglas66J8T]

BTW, that worked perfectly. Thanks again!

[peter.horvath6V6K3]

The color correct shader should be displayed properly in the viewport in C4DtoA 4.0.3.

[mdouglas66J8T]

Awesome! Works great. Thanks so much, Peter.

[mdouglas66J8T]

It's fixed!