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Alembic Import: Visibility
Confirmed, NormalPublicTO DO

Description

System Information
Operating system: Microsoft Windows 10 Pro, 10.0.18362 Build 18362
Installed Physical Memory: 64.0 GB
Graphics card: NVIDIA GeForce GTX Titan Black, Driver 26.21.14.3064

Blender Version
Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: f6cb5f54494e, type: build date: 2019-07-29, 09:44 AM

Short description of error
When importing Alembic files, visibility is not recognized by Blender as it is in other 3D applications. This is important when using multiple proxy objects in another application that need to be invisible when imported.

Example Alembic with Visibility

Exact steps for others to reproduce the error

  1. Turn off the visibility of an object in the Outliner (I tried this with Cinema 4D and Blender)
  2. Export Alembic
  3. Import the file

Blender does not recognize the Visibility properties

Example Blend file with Example Alembic attachment above

Implementation of other Alembic Properties may also be considered as in Cinema 4D's Alembic Import Dialog

Event Timeline

Latest Blender 2.81 rBce2368cf69f5 same behavior...
IMO, not a bug/error yet a feature/improvement or so on..

Philipp Oeser (lichtwerk) lowered the priority of this task from 90 to 80.

In a way this is similar to the lack of importing e.g. Focal Length (T54050: Camera focal length animation not importing), or Custom Properties (T50725: Alembic export doesn't take 'Custom Properties', as alembic non-standard data.).

Right now, Alembic in blender is based on modifiers and constraints, so that streaming will work and everything is updated when the .abc gets updated (well not entirely, but almost).
So (for me), this looks like a similar problem: If support for visibility is to come, it should work with something like D2324: Alembic: F-Curve cache modifier to lookup arbitrary property animations. (supporting animations and doing the disc read automatically without the need to reload an .abc manually if anything in there changed...).
@Sybren A. Stüvel (sybren): what do you think? Of course reading visibility once could be an option [but I think the F-Curve cache modifier sounds like the way to go, no?]

That all being said, this is not really a bug, but a feature request, question is if we keep this as TODO for T69058: Alembic integration improvements?

Will let @Sybren A. Stüvel (sybren) decide...

We have the same problem:

As you can see, the rigger used "Write visibility" option to swap between face parts. In Blender - all planes are visible.

Here are the Alembic file and the texture for the swapping face parts.



Moreover, in the beginning, the rigger used moving UV's as a way to stay with the same plane and still swap between the faces texture grid, but it also didn't work in Blende...

This is indeed not a bug, it's simply a property that's written to Alembic and that's not read by Blender. Alembic is quite bad in this respect, in that there is no well-documented open standard in which such properties are defined. I'd be very happy if you can prove me wrong on this one.

Features like this one and the others @Philipp Oeser (lichtwerk) mentioned should probably wait until T69046: Cache loading via animation system has been implemented. That will give us a much better way to load arbitrary properties from Alembic.

Sybren A. Stüvel (sybren) lowered the priority of this task from 80 to Normal.Sep 17 2019, 1:58 PM
Sybren A. Stüvel (sybren) edited a custom field.