Mesh lights not rendering with Batch Render

[njmb1]

Hi, I have a scene with traffic lights that I rigged so they change by moving the mesh light to each color light at the right time. If I render in renderview or render sequence, the lights render perfectly. But if I batch render, the lights don't show. My understanding is render sequence and batch render do the same thing, just inside Maya or outside Maya. But this seems weird, so I'm hoping there's a fix or reason. My searching online found solutions for if they weren't rendering at all, like turn off normalize and make sure only the mesh or the light is visible. I tried those without luck. My mesh isn't visible anyway, since it's both hidden in other mesh (so there was no point in leaving it visible) and I just needed the light. If anyone has any ideas, that would be great. Also, I'm using Maya 2020 and Arnold 4.2.2. I also can't upgrade Arnold because it won't work yet with Golaem, which I'm using right now. Thank you.

[Stephen.Blair]

What kind of rigging? Almost sounds like something isn't evaluated in batch (non-UI mode).

Are the lights there, but in the wrong place (off screen maybe) ?

An Arnold log (Info-level verbosity) shows the number of lights. You could compare a render in the UI with a batch render.

Instructions for generating full verbosity log files are available for MtoA, MaxtoA, C4DtoA, HtoA, KtoA, and Kick.

[njmb1]

@Stephen Blair

The lights are definitely in the right place, because I can see them in the viewport and in any render that isn't batch render.

For the rigging, I put locators in the casing for each light (each light has a semi-transparent front part to control the color or shape, like with the crosswalk lights) and then parent constrained the mesh light for each total light to the locators and just use space switching the move the mesh light. I'm working on a crowd scene with Golaem, so I also have the Golaem traffic system connected to my lights to control when to switch them. Those are connected with remap value nodes and multiply nodes.

I haven't looked through a log before, so I could definitely be missing something. But it shows all my lights are there. The only warnings I see that I think would apply is on some of the light casings, the shaders for them say to use RGBA instead of RGB on the floatCorrect nodes I used to better control opacity. Except I don't see how to change that, and like I said, they render correctly everywhere else. Do I need to use a different node to control the opacity? I used these so I could use values instead of a color.

What might the difference be between using the Render Sequence, which works, and Batch Render, which isn't?

The other thing I just noticed when trying the batch render again on a couple of frames, is that the light that is definitely switched to green in any other view or render has the red lit up on the batch render. The tif image is too large to attach, so here's a google drive link to it: https://drive.google.com/file/d/1es3CebH3kEmf8EPcvDji8CEW8jcWTbF2/view?usp=sharing

It's the traffic light on the right that should be green, but it's easy to see red is lit here. The crosswalk light on the same light should also be showing the walking person and not the stop hand. It's like batch render doesn't get updated information.

I appreciate your help. Thank you!

[Stephen.Blair]

It sounds like something is not evaluated when there's no viewport/UI.

It's not a problem during the actual render, it sounds like a problem with what is exported from Maya to Arnold. When MtoA exports the mesh light and its associated mesh, MtoA is basically exporting a baked version of everything that drives transforms of those objects.

I expect if we export an ASS file, we'd see the mesh light in there, but in a different position.

[njmb1]

@Stephen Blair

Thank you. Is there a way to correct that if that's what's happening? I exported an ASS file, but I can't render it. I get an error "line 70721: node " CrowdProcArnold" is not installed" which should be a Golaem thing, but Golaem is fully installed. I haven't dealt with ASS files before now, so maybe I did something wrong? When I change the draw mode to shaded, objects I referenced in and duplicated aren't there, except the originals (which are gigantic, haha). The golaem stuff isn't there either, and shaded did actually make any of my shaders show (if it was supposed to). I'm not sure how to tell where the lights are. I don't know if you can open the file without Golaem, and it's too big to upload here, but here's a Google drive link in case that helps: https://drive.google.com/file/d/1_vaosJmtFuzZ6JbEp9kJ3ttRfvAa0VL2/view?usp=drivesdk

Thank you.