Hello,

I encounter major problems when exporting an alembic sequence from houdini 17 to maya 2018.
I traced the problem down to the “build hierarchy from attribute” option combined with rendering frame ranges into an alembic-file.

Attached is a test file, to rebuild/illustrate the problem:

export an alembic file with build hierarchy from attribute “name” ON
—> import in Maya causes crash or empty transform nodes, but the hierarchy would be there

export an alembic file with build hierarchy from attribute “name” OFF
—> import in Maya with animation works fine - except that I don’t get the correct hierarchy I’m aiming for.


Is someone encountering the same behaviour and has a solution for that? Or is it only at my system/setup?
I’m working with Houdini 17.0.352 and Maya 2018.5
(but it didn’t work in any maya version between 2017 and 2018.5)

Any help would be appreciated. Thanks!

Joko

Read this page, and it should resolve your issue. http://www.toadstorm.com/blog/?p=435 [www.toadstorm.com]

Your example file is missing a hierarchy attribute. Your name attribute can be used to partition your scene's hierarchy when the alembic rop is in object mode, but yours has a sop connected, which precludes that workflow. When writing from sops, the hierarchy must be determined by a path attribute, which in maya turns into the group nodes and shape nodes that make up the scene.

For example to create the maya scene graph:

You will need path attribute values of: “/my_root_grp/sphere/sphereShape”, “/my_root_grp/box/boxShape”, “/my_root_grp/grid/gridShape”
on your sphere's, box's, and grid's polygon primitives respectively.

It is also possible to create this hierarchy explicitly using geometry objects to separate your scene into different objects. Then the alembic rop node can build the hierarchy directly from your scene's node hierarchy.