- I have alembic from Maya which I'm importing as packed alembic, attaching some attribs and exporting using path to get the same hierarchy and transforms as original, however point/primitive attributes on packed prims are not being exported

- the same is the case with plain export of packed primitives with attributes

- I don't want to unpack, include attribs in and pack again since that would prevent it from using instancing and reusing the same geometry every frame (as only transfrom and my per object attribs are animated)
so it would result in super huge files since it will treat it as different geo every frame, and I will loose my packed transforms

any way to do that?

- similarly I have some shape attribs in maya, which come in packed inside of the packed alembics, while I would expect them to be living on top of them as they are per object/shape and not per point/primitive

tamte
- similarly I have some shape attribs in maya, which come in packed inside of the packed alembics, while I would expect them to be living on top of them as they are per object/shape and not per point/primitive

We have written a custom python SOP which is using the HOM Alembic Extension to promote those attributes and make them accessible on the Packed Geometry. The performance is pretty good even with huge datasets.

Additionally you could export them as a User Property instead of Alembic Geometry Attributes. The Alembic SOP supports loading User Attributes in H14. However you probably need to reformat those to actually work with them as they are loaded as a JSON dictionary.

Cheers,
Dennis

Thanks Dennis,

For getting it in I'm currently unpacking and copying the attribs to packed, however Python may actually by faster I'll check that

I was thinking about user properties, but nothing comes in in that dictionary from our Maya exports (could be due to our custom abc exporter though), I will experiment with that more, the most important thing now is to export packed attributes from Houdini

I tried exporting prim attrib abc_userProperties with reformated attrib to JSON format, like {“abc_a”:“1000”}, however nothing comes in either

Any Idea on how to export abc_userProperties correctly?

Hey tamte,

did you find a solution for that problem ?

Cheers,
Dome

I would also like to know how to actually export abc_userProperties correctly…

If I directly import as “Alembic Delayed Load Primitives” and export it right after it with the Alembic ROP everything works fine.
But as soon I unpack, edit and transfer the “abc_UserProperties” back and pack it again, the abc_userProperties don't get exported correctly.

Qwertzus
But as soon I unpack, edit and transfer the “abc_UserProperties” back and pack it again, the abc_userProperties don't get exported correctly.

Both “abc_userProperties” and “abc_userPropertiesMetadata” are needed.