Issues with Maya Alembic Export in Embergen - Transformations Problems Upon Import

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I have experimented with numerous settings and combinations, but I have encountered challenges with the alembic importer when using ABC files created with Maya. Specifically, issues arise with rotations when working with models composed of multiple meshes, as well as with cameras. These rotational issues have proven to be particularly problematic. To circumvent these challenges, I have resorted to exporting the ABC files from Maya to Blender and then re-exporting them from Blender. This workaround enables Embergen to correctly read the ABC files.

The FBX cameras exported from Maya are also exhibiting issues, whereas those exported from Nuke are functioning as expected. This has led me to suspect that Embergen may not be fully compatible with Maya.

working with Maya 2024 and Embergen 1.0.2 (maya 2023 also had the same issues)

Here are some of the methods I have attempted to resolve the issues with the Alembic export:

  • Exporting the Alembic files using world space transforms.
  • Using the Bifrost ABC writer, which appears to address the problem. However, this method has limitations as Bifrost graph is not yet capable of exporting cameras, and the Alembic export process can be complex for just a cache export.
  • Baking the camera keyframes prior to exporting them to ABC or FBX.
  • Removing meshes from groups, cleaning them, and re-exporting the ABC files with world space transforms.
  • Import the Alembic cache into Blender, and then re-export it (without any additional settings or options). This method has also proved to be useful in exporting cameras. Alternatively, the Bifrost Graph ABC writer resolves mesh export issues but is unable to pack the cameras.
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Hi there, thanks for the detailed post. We have certainly experienced these issues as well. We have had to reverse engineer the importing of Alembic objects as there is minimal documentation for software developers. I have no experience in Maya so I can’t troubleshoot very well, but I’m interested in what you mean by exporting in world space transforms, is that not common? And what does that address in EmberGen?

It’s definitely annoying to do the Blender workaround but I’ve found that to be the most reliable way of getting around these issues. I’ll relay this post to our dev team to see if this helps illuminate anything so I do appreciate the information here!

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Thank you so much!

In the Maya exporter, there’s an option called “world space” in the advanced options tab during the export process. I’ve encountered similar issues in the past with other alembic workflows, and checking this option has helped solve the problem. When this option is enabled, the vertex animation will disregard group transformations and only adhere to the world transformations, effectively resolving any transformation issues. However, in the case of Embergen, toggling this option on or off doesn’t seem to make a difference, looking forward to future improvements :slight_smile:

Once again, thank you for your response. You’re doing an amazing job with this tool, and we’ve already incorporated it into our workflow!

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