Seeing cutout opacity in Object Mask AOV

[shawn]

I want to create an Object Mask AOV for some cloned planes that have 2D artwork mapped to the Cutout opacity input of a Standard Shader to create some flat pattern detail over underlying objects. Simply applying an object mask to the plane creates a white rectangle; the pattern doesn't come through. If I isolate the plane in the render the pattern IS visible as an alpha.

I assume there's some way to link that Standard Shader with the cutout pattern to a custom AOV thing, but I'm unclear as to what connects to what.

Any suggestions? Thanks.

[peter.horvath6V6K3]

Connect your shader to an aov_write_float shader and enable Blend opacity.

Actually the object mask tag should do the same, blending the opacity by default. I'll fix that in the next release.

[shawn]

Thanks for the response; sorry for the delayed reply.

Unfortunately, I'm not having any luck making this work. I've attempted to recreate the setup you've described, but my custom AOV for this cutout artwork is just producing black.

I've attached a zipped folder with a reduced version of this scene. Can you spot what I've messed up?

Cheers

customaovtest.zip

[peter.horvath6V6K3]

Your scene looks good to me, and the AOV seems to render properly. What's your C4DtoA version?

[shawn]

Thanks for the reply, Peter; I appreciate it.

I'm using v C4DtoA 2.3.1.2.

So you're saying that you loaded my test scene, opened the IPR, selected MatteAOV as a display and the dots on that artwork appeared as white dots over black? You didn't make some other change to the scene? When I do that I just see black.

TBH, I'm not really understanding the workflow for this. The Field Nozzle Plate object in my project has a material called Mandrel Bumps applied to it. I copied and pasted the nodes from Mandrel Bumps into the material called AOV, routing that into an AOV write float node, specifying MatteAOV as the custom name. It's not clear to me how the material called AOV is doing anything since it's not applied to any object in the scene. How does the MatteAOV know where in the scene that Mandrel Bumps material is being used? The AOV material isn't even accessing the Mandrel Bumps material directly; it's just using copies of the same nodes as Mandrel Bumps.

Cheers,

Shawn

[peter.horvath6V6K3]

Right, you have to apply the material with the AOV write shader to the object, otherwise it's not evaluated. That's what I did, just replaced your current material with the one named 'AOV'.

[shawn]

Thanks for the clarification; it works and makes sense. I should have paid more attention to the "passthrough" element of that node.

Best.

Shawn