I have a number of FBX files here that were exported, from LightWave data, by Modo 301. A few of the files are larger than 2 GB on disk. Houdini 10 (OS X) seems to be unable to import these files - it just puts an empty entry in the node graph and gets no further. No error message is shown.

Are FBX files subject to a 2 GB limit? I've seen the same issue using the FBX 2010 importers under Maya 2009 SP1 (64-bit, Windows).

How long, in your experience, does it take to do that? Have you tried exporting a part of the same geometry set that is smaller than 2Gb to see if you still get the same behaviour?

I'll keep looking into it , but from what you describe it could quite possibly be an FBX SDK limitation. The fact that there is no error, but no objects get created, implies that it could be the FBX SDK feeding Houdini incorrect information for some reason, and the fact that Maya does the same only reinforces that theory.

Have you tried importing the same file back into Modo?

Like Maya, the result of an empty scene (bar an empty node in Houdini's case) is instantaneous. There's no sign of any computation or heavy disk activity in either case.

Given that all other FBX files exported the same way have imported (into Maya) without issue, I wasn't suspecting an export issue, but wondering if there was a hard-stop due to file size, either due to application limitations or FBX itself. Autodesk seem to not be aware of an issue. That said, I've just been told that Modo also fails to import the .fbx it created - with an instantaneous error like all the other applications of an empty scene.

That's interesting, because a test file I created (~3.7 Gb) exported with Houdini kept going all night when I tried to import it back in. I eventually had to kill it before it completed, but it never gave the blank scene you're describing. This was on Windows 64-bit, however.

The fact that this error manifests itself exactly the same way in all three applications highly likely means this is something internal in the FBX SDK going wrong. Also, the FBX SDK Mac libraries are known to have problems which other platforms do not.

I'll try it on a Mac, as well, to see if it is something specific to your files or to the Mac platform.

I've just tested my file on a Mac, and it sits there doing the work. I don't get an immediate empty scene.

So this could be a combination of something particular in the way your files are exported, as well as something going wrong with the FBX SDK itself.

philstopford
I have a number of FBX files here that were exported, from LightWave data, by Modo 301. A few of the files are larger than 2 GB on disk. Houdini 10 (OS X) seems to be unable to import these files - it just puts an empty entry in the node graph and gets no further. No error message is shown.

Are FBX files subject to a 2 GB limit? I've seen the same issue using the FBX 2010 importers under Maya 2009 SP1 (64-bit, Windows).

Hello philstopford,

Are the FBX files your importing full scenes or motion data?
If it's motion data, you can break your animated elements into different files?
This is what I have done in the past on large productions.
If it's full scenes, export your curves in a separate fbx file. That will bring the file size down considerably.

Cheers,

Frank

It's effectively a full scene - with a single object (geometry), 1 light and 1 camera. The object has a large number of morph targets (blend shapes). There is no animation as such, but the geometry variations seem to be the main cause for the large file size.

I'm looking to see if I can generate a working FBX using an alternative pipeline, as Houdini doesn't seem to be able to directly read in current LWO objects. That would be a useful enhancement for Houdini, though.

Autodesk have the content and are looking into it. It seems that Modo exports can have issues, but they are also puzzled by the reaction of the importer and their convertor in this case.