Alembic I/O.

Anyone else trying to compile the branch in windows with HDF5 support?

I managed to build it but it keeps crashing when loading an HDF5 file, saving seems to work ok.
Here ( it says that HDF5 does not like to be compiled with /MT flag.

The runtime should be /MD or /MDd whether you are building dynamically or statically.
Using /MT or /MTd, requires advanced changes to the supplied HDF5 libraries.

But it seems to be required to be able to build blender.

I try it, it works fine, but exporting from 3DSMAX for example the same mesh sequence from RealFlow takes DAYS, or even weeks. I know it can be fixed, I was emailing the author, but yeah none like to spend time imrpoving something that only few will use. But anyway, great work by the author of Blembic :slight_smile:

I have not been able to build successfully with hdf5 enabled (which i think was a combination of alembic 1.6 and hdf5 1.10 but don’t pin me down own that) , best i got was it not crashing, but refusing to read any hdf5 files however even the alembic tools (Abconvert etc) refused to work on known good files such as the octopus, so it seems more like a problem between alembic and hdf5 (on windows, i checked with some linux users on irc and they were able to import the octopus just fine on linux) than the blender plugin. Given how hard it was to even find hdf5 example files, i decided it was a waste of time and gave up (for now)

Hi, I uploaded a new version compiled with HDF5 support.

Get from

The old version without HDF5 is still in there in case this one doesn’t work.

A new uptodate linux build:

Still alembic 1.6 and hdf5 1-10-patch1 until this is sorted out.


Thx guys ! I will try the windows build.

Thx guys ! I will try the windows build.

I have updated the windows build to match the linux build hash and be more in sync.

Main difference is that the windows build uses alembic master, not 1.6 and HDF5 1.8.17.

Alright gang, I pushed some quick and dirty changes:


We’ll see where that goes. (It should also work for particles.)

Wooow!!! This is one of the best video i’ve ever seen!!! Thank you Kévin for your efforts!

Nice, well done !!!

You are a genius sir! Thank You for this amazing work! I will try make a few more tests :slight_smile:

Uploaded a new build with latest changes.

@KWD, to avoid building repeatedly on a single day I will make the next build when you think is appropriate for testing new features. Let me know when you need it.

seems slow but working!, that’s great

Yo, so updated linux too:

In a fast test i could now load and play the ape fracture completely.


Is that slow speed in the Realflow demo from the Alembic reading or Blender’s viewport?

It comes from the reading, there is half a million verts + over a million faces to be read. I haven’t looked into optimizing this yet.

Fjuhec - Your builds aren’t linked, only text appears. Can You please fix it?


It’s working really well and exceptionally fast ( for streaming mesh )! Great work KWD!

I have made a few more quick examples that I am hopeful can help tweak it further:

  1. Mayas BIFROST.
Since a lot of studios/indies will use these two softwares hand in hand, it would be highly desirable to be able to import such simulations.

Current status:
Blender crashes (win build)


2) Houdini FlipFluids:
Current status: Imports wonderfully and very fast. Whitewater particles are missing(black particles on gif). I assume this is not going to be supported for now? (not critical)


  1. Realflow Hybrido sim:

This time I did not output a mesh sequence but used the stitcher.exe tool that ships with RF (2013+*) which condenses all individual .abc files into 1 single one. This is desired procedure used for other apps that I also hope solves performance issue.

Current status: Blender crashes

Hope it helps. I will do some more tests this weekend.

Thank You again for this amazing work!

Sha checksum: c38f85bf7a061d37fd35fb68a3c2033a424b46a2