I'm developing a hair dynamics simulation system within Houdini which imports guide curves from Maya, simulates them in Houdini and then spits them back to Maya cached.

However, in my not so successful stress test I did tonight, exporting an FBX with 3.000 curves with 9 points each, and 300 frames is not yet complete after 14 hours.

Cacheing the geometry in Houdiini to *.bgeo-files takes about a minute, and that stores more data than the cache files, so I don't see why it would have to take so long. And the same geometry exported from Maya is also significantly faster.

Is anybody aware of a way to get the curves from Houdini back to Maya in a more efficient way? Perhaps another cache system?

The topology and naming of the curves is the same, so preferable would be to only export the cache and apply it to the existing curves in Maya.

I'm not sure where the slow down is but it might be on the FBX SDK side as well. As for other caching solutions, you might want to consider MDD. I don't think Maya has native MDD support but I hear a lot of people using PointOven. There might be some free scripts/plugins for MDD support in Maya.

Can you attach a quick example file for us to test? Also, are you exporting the whole scene from Houdini, or did you point the FBX exporter to just the curves?

Wow, MDD sure sounds interesting. Weird that I've missed it before. I'll give it a go later. However as far as I could see the workflow with MDD isn't exactly ideal for lots of objects. But I'll soon find out.

I posted a scene similar to my other scene for you to test with. However I suspect that the problem is that there is just too many objects.

The scene was 34mb if I use my setup so I've attached the script which constructs it. Just run the script and select “Fast feedback, slow separation”.

edward
I'm not sure where the slow down is but it might be on the FBX SDK side as well. As for other caching solutions, you might want to consider MDD. I don't think Maya has native MDD support but I hear a lot of people using PointOven. There might be some free scripts/plugins for MDD support in Maya.

http://www.ef9.com/ef9/PO.htm [ef9.com]

Used in a lot for Maya and Lightwave over the years on Windows, generally works great. However, there is no PointOven release for Linux.

Phunt
However, there is no PointOven release for Linux.

Yes, and as I implied, it isn't free.

edward

Phunt
However, there is no PointOven release for Linux.

Yes, and as I implied, it isn't free.

Oops… Forgot about the “free” part. Things you sometimes take for granted when you work in a studio.

Well, I've kinda solved the export issue now. I'm making a polygon object of all the curves, retaining the vertex numbering. This exports very fast and playbacks well in Maya. Now the only thing left is to find a way in Maya to deform the existing curves with this geometry. Which might prove a bit more challenging. But that is a whole other story completely.