According to this documentation, it looks like Houdini doesn't support custom attributes being exported on an fbx object (like maya, max and blender do)?

https://www.sidefx.com/docs/houdini/io/fbx.html [www.sidefx.com]

it does specifically mention that user layer data attributes are supported (under the attributes section). What is this referring to and how do I go about creating these in Houdini? I could not find any other information related to the "user layer data". Any help would be appreciated.

Please anyone knows? I have the same problem.
I have a fbx with custom data that I use in Unreal as fbx metadata.

I can import this fbx in Houdini and I can see the custom data.
However when trying to export it from Houdini using ROP FBX Output, the new fbx loses all custom data.
Importing this one in Unreal has no meta data.

Same here, asked the same question recently here https://www.sidefx.com/forum/topic/91063/ [www.sidefx.com] (probably worth deleting that thread then and keep the conversation going in here)

For anyone looking for a solution.
You can see the FBX metadata if you import the FBX using File -> Import
The metadata will appear as spare parameters. They can be seen when you select the node.

If you import using the file node it'll not be spare parameter.
It'll appear as primitive parameter , but it'll not be preserved on export.
It is only preserved if you use File->Export.,

Hi, Bumping since I would also like to know how to preserve custom attributes on fbx export. Although it seems like keep numeric attributes.

I've solved this by writing a small CLI tool named "fbxup" using the official FBX SDK. I haven't publicly released it as a standalone tool yet, but you can find it as part of my H20 tech art challenge contribution: https://www.sidefx.com/forum/topic/93085/#post-410115 [www.sidefx.com]

Have you had any chance to make this a standalone hda? I'm running into the same issue of being incapable of maintaining user properties on an FBX file on export.

Opheliar
Have you had any chance to make this a standalone hda? I'm running into the same issue of being incapable of maintaining user properties on an FBX file on export.

I'm planning on developing a native Houdini node using HDK in the upcoming weeks that allows you to write user properties into an FBX. I will update my progress in this thread.