[Bf-committers] Alembic triangulation

[Adriano Oliveira]

Kévin,

I treasure your Alembic iniciative and I wish to help. I am just performing
some tests before judging what it is or is not a bug. In the prosses I will
give some constructive feedback here.

Blender-Alembic-Blender seams ok. I am performing some testes in this
plataforms: Unreal 4.13, 3ds Max 2017 (educational), Maya 2017
(educational).

Findings on importing Alembic character animation from Blender:

1. Unreal 4.13 (preview 2): Issues with rotation (y-z) and scale (cm-m).
Bad normals from Blender (ok from Max). Animation and meshes are ok.

2. 3ds Max 2017 (Educational): Rotation/sacale ok. Bad normals. No
materials. Animation and meshes are ok.

3. Maya... soon...


At this moment, I would say that normals are problematic.

I will report bugs as soon as I have solid tests.



*Adriano A. Oliveira*
Professor Adjunto do Curso de Cinema e Audiovisual
Universidade Federal do Recôncavo da Bahia (UFRB)
Centro de Artes Humanidades e Letras (CAHL)
Matrícula: 1673892
(71) 99181-0123 [VIVO] / (71) 99146-8523 [TIM]

2016-08-19 23:56 GMT-03:00 Kévin Dietrich <kevin.dietrich at mailoo.org>:

> Please use the bug tracker [1] to report bugs/issues, with simple
> example files to reproduces them.
>
> If one software can open an Alembic file from Blender without issues,
> and another can't, for basic things like normals, then the bug is mostly
> likely in the other software, not Blender, we don't do anything fancy
> here. Also, can 3ds Max import materials from other software without
> issues?
>
> Le 2016-08-20 04:38, Adriano Oliveira a écrit :
>
> > ....
> >
> > bf48750
> >
> > 3) Bad normals when importing from Blender-Alembic into Unreal 4.13 and
> 3ds
> > Mac 2017.
> >
> > 4) 3ds Max doesn't import materials from Blender-Alembic. Unreal 4.13
> does.
> >
> > *Adriano A. Oliveira*
> > Professor Adjunto do Curso de Cinema e Audiovisual
> > Universidade Federal do Recôncavo da Bahia (UFRB)
> > Centro de Artes Humanidades e Letras (CAHL)
> > Matrícula: 1673892
> > (71) 99181-0123 [VIVO] / (71) 99146-8523 [TIM]
> >
> > 2016-08-19 19:36 GMT-03:00 Adriano Oliveira <adriano.ufrb at gmail.com>:
> >
> > Kévin,
> >
> > I am very interested in the workflow Blender-Unreal through Alembic. The
> > idea is to use Unreal for real time rendering.
> > Alembic in Unreal 4.13 is in preview state, so it will improve a lot.
> >
> > Some findings:
> >
> > 1) Alembic is very usefull to export destruction simulations. I used Cell
> > Fracture to explode a cube and it produces houndreds of n-gons objects.
> On
> > importing into Unreal, it gives errors. I think this would justify an
> > triangulation option, as in OBJ export.
> >
> > 2) I have some crashes on importing Alembic animated characters into
> > Blender or Unreal that was exported without Flatten Hierarchy.
> >
> > ;)
> >
> > *Adriano A. Oliveira*
> > Professor Adjunto do Curso de Cinema e Audiovisual
> > Universidade Federal do Recôncavo da Bahia (UFRB)
> > Centro de Artes Humanidades e Letras (CAHL)
> > Matrícula: 1673892
> > (71) 99181-0123 [VIVO] / (71) 99146-8523 [TIM]
> >
> > 2016-08-19 19:10 GMT-03:00 Kévin Dietrich <kevin.dietrich at mailoo.org>:
> >
> > Le 2016-08-19 23:53, Adriano Oliveira a écrit :
> >
> > Hi,
> >
> > Is it possible to have an option to triangulate mesh on Alembic export.
> I am trying to import a animation from Blender to Unreal 4.13 and the late
> > ask for tri or quad faces.
> >
> > Also it would be nice to have Z to Y convertion options, as long as
> Unreal rotates the Alembic imports form Blender.
> >
> > Congratulations for the grate job!
> >
> > *Adriano A. Oliveira*
> > _______________________________________________
> > Bf-committers mailing list
> > Bf-committers at blender.org
> > https://lists.blender.org/mailman/listinfo/bf-committers
> > Hi,
> >
> > Adding an option to triangulate meshes in the exporter wouldn't that
> > much of a trouble (though it would have to wait for after the 2.78
> > release), but I have to ask what prevents you from triangulating the
> > meshes before exporting? If you've got a lot of objects to triangulate,
> > a simple Python script can be written to automate the process. Shall it
> > be a destructive operation, or shall it preserve the state of the meshes
> > (meaning meshes in Blender are not triangulated, but the exported ones
> > are)?
> >
> > For the axis conversion, Alembic files written from Blender follow the
> > Alembic Y-up convention, so I guess this is already what you want? I do
> > plan on adding support for more (custom) axis conversions though.
> >
> > Regards,
> >
> > Kévin Dietrich.
> > _______________________________________________
> > Bf-committers mailing list
> > Bf-committers at blender.org
> > https://lists.blender.org/mailman/listinfo/bf-committers
>
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