Rendering Grease Pencil objects on headless, no GPU render farm machines in Blender 2.8

Archive Blender Development
1

(got a suggestion from a user at blenderartists.org to post this question here)

My company has been running into problems when trying to render Blender 2.8 scenes on headless, no GPU render machines. We are using AWS Thinkbox Deadline.

We are able to get Cycles to render scenes with just geometry successfully on the farm. But when we try to render Grease Pencil objects, we get the OpenGL 3.3 error dialog box, and the render fails.

We are aware of the MESA 3D/OpenGL32.dll workarounds that are out there, and we have successfully rendered a scene with Grease Pencil objects using it. But before deploying this method on 80+ of our farm machines and potentially opening ourselves up to issues further down the line, we are reaching out to the community to ask the question: Has anyone been able to successfully render Grease Pencil objects using Cycles on a headless render machine with no GPU?

I haven’t found much info to back this up, but is Grease Pencil completely reliant on OpenGL? If so, it’s pretty clear why we can’t get it to work unless we use the modded drivers.

Thanks,

-dp-

2

Yes, that is correct Grease Pencil is drawn using OpenGL. So when used in a render farm OpenGL support is needed. This can be via GPU+driver or software emulation.

3

Even if I have a hidden grease pencil object in my scene Blender expects a GPU. So even in this case my background render fails on a machine with no GPU.

Is there a global way to ignore all Grease Pencil objects at render time without
requiring modifications to the scene? I don’t see a command line argument.

Thanks,
Tom

4

Have you tried to remove the Grease Pencil object from your viewlayer? When removed from the viewlayer it would not appear in the list of objects to be rendered and to my knowledge should just render fine.