Blender Alembic Import

Hello guys. I’m trying to include Blender in my workflow and I have been practicing with it for a while now.
I’m using Houdini to make my animation and I always exported Alembic files from Houdini and I used them in various software, like C4D but now I am trying out Blender and the Alembic Import is very very slow.
I feel like i’m doing something wrong especially because I tested the same .abc file in C4D and it loaded fast and I could play it in the viewport; and in blender the viewport is very slow and sometimes it even crashed whilst trying to get it into the scene.
I feel like there is something weird going on, like Blender reads the Alembic differently, but how can I optimise that?
How do you recommend I do the importing of more complex animation into Blender?
The Houdini export is very clean since I am only testing, so no point attributes, just geometry.

If you’re using instances, then that’s likely the cause. As far as I know, Blender still doesn’t support importing alembic instances and will create unique a new geometry datablocks for each object.

My workaround has been to write custom importer scripts based on specific Houdini setups. Those aren’t public though and certainly not easy to use.

The alternative would be to export plane proxies of the instances and redo the instancing using duplifaces and collections in Blender. You should be able to partition the file hierarchy based on an attribute like path or name.

Thank you for the response init_pixel.
I forgot to mention that I’m not instancing particles or anything complicated. The task is pretty simple. I also tried with a Mixamo character. Get it to Houdini, and export an alembic for blender and the animation is slow when it gets played. I mostly use Houdini and i cleaned the alembic to be as light as possible and not have to many confusing objects like instances.
I’m just trying to transport the geometry I make and process in Houdini, but I’m confused what does Blender need from the alembic? I’ve tried many alembic combinations of geometry animations and imported it in Blender and it’s still slow.

Hi, it really depends on the size of the data. If it is big, it can be slow obviously, but it may be that Blender is just slow to evaluate the modifiers if you have a large number of objects. It could also be that loading the data for each frame is just too expensive on your computer, while other software might have caching mechanisms which Blender lacks, and is unlikely to have in the forseeable future.

Blender does not need anything special from Alembic, apart from clean data (which you seem to have). If it appears to be too slow, and especially if it crashes, maybe consider reporting a bug. You would need to provide files for reproducing any issues (again, especially crashes).

If you cannot, or do not want to, share files publicly, feel free to DM me here as I am the original developer in this area, and I am also currently developing new features for it, and I’d be happy to help figuring out what’s wrong here.

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