.abc Loads On Ubuntu Fails To Load On Windows 7
Closed, ArchivedPublic

Description

System Information
Windows 7 and Ubuntu 17.10
nVidia 660 and nVidia 1070
Operating system and graphics card

Blender Version
2.79
Worked: (optional)

Short description of error
On Ubuntu, I exported a nurbs circle from Houdini Indie using the Alembic ROP.
On same Ubuntu I run Blender 2.79 and import the .abc file.
It works as shown.

I try to import the same .abc file using Blender 2.79 on Windows 7 and a console error is produced. The file is not loaded.

Details

Type
Bug
Atomic (atomic) updated the task description. (Show Details)

is this exported as HDF5?
afaik, blender releases build without it? WITH_ALEMBIC_HDF5 is off and not supported anymore, see 2.79 release, should now use Ogawa always.

So you might have a custom build on your ubuntu?

Philipp Oeser (lichtwerk) triaged this task as Incomplete priority.Jan 19 2018, 6:47 PM

should be an option in houdini, see here

Marking as incomplete until this question is out of the way...

I can't load this file neither on linux nor windows, it's also suspiciously small you sure it's not just a corrupt file?

Well, here is what Houdini 16.5 says to the attached .abc file.

hm, true, file seems to be currupt, no? abcecho and abcls even crash...

Atomic (atomic) added a comment.EditedJan 21 2018, 3:04 PM

It does look like the original attached file was corrupted on upload somehow? I am re-uploading the same exact file, which does work on both Houdini 16.5.332 and Blender 2.79. I have removed the bad file from the first post.

My Ubuntu system is a standard install of 17.10. I installed Houdini, Redshift and Blender. I am no Linux guru so there are no other tools installed.

Please give this .abc file a try.

Atomic (atomic) added a comment.EditedJan 21 2018, 3:16 PM

I re-conducted the import test on Windows 7 downloading the new file I posted.
This does produce working results. However, the result in 2.79 are wrong while the results in 2.78c are correct.

In both cases, there are extra points on the circle causing it to not form a perfect nurbs circle.

In 2.79 it looks like Blender treats the nurbs circle import as a mesh based circle that has been turned into a polygon based circle.

In 2.78c the import looks much better but has over hanging extra points.

It looks like we are losing functionality in Alembic import on 2.79, compared to 2.78c.

Philipp Oeser (lichtwerk) raised the priority of this task from Incomplete to Normal.Jan 30 2018, 5:20 PM

Well hm, afaiks this is a matter of setting the curve resolution.
In 278c curve resolution wasnt really considered at all thus defaulting to U=12

in rB5bdbc88ab81891eff0 this (curve resolution) was implemented [export>import in blender works], but for files not having this new user property set this would now default to a resolution of 1.

While not really a bug, I think D3031: fix T53839: better default for curve resolution in abc import makes more sense? @Sybren A. Stüvel (sybren) : could you check?

@Atomic (atomic) please attach example files to the task description, so that people interested in solving this don't have to read through each individual comment to see which file(s) they should be using.

Apart from the resolution now defaulting to 1 instead of 12 (let's discuss that further in D3031), is there anything else that could be seen as a bug in Blender?

Philipp Oeser (lichtwerk) closed this task as Archived.Mon, May 7, 12:00 PM

Seems like a default resolution of 1 (current behaviour) is indeed the wiser choice here (see reasoning in D3031).
Will archive this then as there is nothing else that can be seen as a bug here afaics.