François, Shaders are not as important as meterials per face assignments. Unreal imports materias names and assingnments form Blender Alembics, but Maya and 3dMax don't. I think it is related to Blender and Unreal beeing Alembic 1.6.
An update of my findings so far: https://forums.unrealengine.com/showthread.php?120948-Blender-2-78-Alembic-Unreal-4-13 *Adriano* 2016-08-22 11:45 GMT-03:00 François T. <[email protected]>: > Alembic doesn't contain any information about the unit. You have to make it > a convention in your project. If in blender 1 unit = 1 meter for you, then > you need to set the proper unit system in Maya which will be in cm at the > system level. We did a patch on the alembic I/O of Maya (you can find it on > the alembic github) which use the unit of the maya scene rather than > assuming that the alembic is in cm (which what is the default I/O in maya > does). But know that Alembic only stores generic unit. > > For materials, there is no such information in Alembic file format. Only > shading groups (or material assignation per face as you might name it). So > you cannot exchange shaders or material parameters with Alembic. You will > need a script in your dcc which binds a material based on it's name and the > shading group stored in the Alembic. (alembic is just a geometry cache) > > cheers, > > F. > > 2016-08-20 14:51 GMT+02:00 Adriano Oliveira <[email protected]>: > > > 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 <[email protected]>: > > > > > 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 <[email protected] > >: > > > > > > > > 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 <[email protected] > >: > > > > > > > > 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 > > > > [email protected] > > > > 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 > > > > [email protected] > > > > https://lists.blender.org/mailman/listinfo/bf-committers > > > > > > _______________________________________________ > > > Bf-committers mailing list > > > [email protected] > > > https://lists.blender.org/mailman/listinfo/bf-committers > > > > > > > > > > > > Links: > > > ------ > > > [1] https://developer.blender.org/maniphest/task/edit/form/1/ > > > _______________________________________________ > > > Bf-committers mailing list > > > [email protected] > > > https://lists.blender.org/mailman/listinfo/bf-committers > > > > > _______________________________________________ > > Bf-committers mailing list > > [email protected] > > https://lists.blender.org/mailman/listinfo/bf-committers > > > > > > -- > ____________________ > François Tarlier > www.francois-tarlier.com > www.linkedin.com/in/francoistarlier > _______________________________________________ > Bf-committers mailing list > [email protected] > https://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ Bf-committers mailing list [email protected] https://lists.blender.org/mailman/listinfo/bf-committers
