Hello,

I've been wondering for a while now why the uv channels order are flipped arround when I export geometry in fbx. I am using the “layer” nodes to add additionnal uv channels in my geometry.

Anyone have an idea?

Thx

It's always been this way AFAIK, but it's a bit of a pain when exporting to other applications, especially game engines (though at least Unity has a UV swap on import option).

The FBX exporter is long in need of an update. It's really quite a pain for exporting to games for instance… consider a single geo HDA which generates procedural geometry. You can't export groups as separate objects in an FBX, and you can't export based on frame (it tries to export a vertex cache). Both of these you can do with OBJ, but then you lose everything an FBX supports (i.e. vert colors is important for games…though again, alpha component support is desirable too). I could go on, but these as basic essentials would be a good starting point.

The only alternative is to use Houdini Engine, which I have started doing, but I really don't like the way it creates (bakes) geometry, especially when lots of versioning is going on. Maybe there's a nice way to customise it, but I need to find the time to find it, and it's not a simple thing to dig into.

When I get time to put some use-case examples together I'll submit an RFE. I've been saying that for…eek, a long time!

Thanks for confirming that AdamT.

I'm exporting to game engines also. I am usualy dealing with 2 uv channels, (texture and lightmap uv) and I just swap them arround before export. But I am working with a case where I have 3 uv channels and the order is flipped arround randomly.

I guess i'll keep using the work arround for now.

Do you guys use modeled and animated characters in Houdini and export them to FBX for Unity?
I just can't get this to work.

I absolutely agree. I'm working in games right now as well. The UV flipping in FBX is a real pain in the neck.

Adam:
You can't export groups as separate objects in an FBX, and you can't export based on frame (it tries to export a vertex cache)

I've written a python script that will do exactly this, but it is a real hack. would love it if .fbx just worked without the assumption of a vertex cache.

We're having his problem over here too. Semi-relieved to see that it's just a bug in the software, and not me going insane.

Would be nice to get this fixed.