Hi everyone,

I’m working in Houdini 20.5 and trying to export a texture I created inside a COP network as a .png file.

Here’s the setup:
• I built a texture using a combination of SDFs and Preview Material nodes inside COPs.
• The result looks correct when viewed through the PreviewMaterial output.
• I connected a ROP Image Output node at the end of the network and tried to render it to disk.

However, when I press Render, I get the following error:

Could not determine source layer size

From what I understand, this suggests that the ROP node can’t resolve the image size from the upstream node.

I’ve tried:
• Setting the Display flag on the node before the ROP
• Forcing a cook by manually viewing the output
• Explicitly setting the Input Node path in the ROP Image Output
• Confirming all upstream nodes are correctly cooking and showing valid image sizes

None of these have solved the issue.
Has anyone run into this when trying to export textures built procedurally inside COPs?

Any help or workaround would be greatly appreciated!

Thanks in advance.

I've just run into the same problem. I haven't found a solution yet.

It seems that in my case some of the ROP AOV Outputs were empty and that was what caused the error, by feeding something into every AOV port it fixed the error.