VFX artist here.
I see cycles do not have support for motion blur on alembic meshes with varying point count.
I find it strange since cycles got support for motion blur on blender fluids and other meshes with varying point count.
Is it possible to point predefined Velocity from an alembic file to cycles? Stored as a vertex attribute.
In the blender manual under alembic it says:
"Blender can be used in a hybrid pipeline . For example, other software, such as Houdini or Maya, can export files to Alembic, which can then be loaded, shaded, and rendered in Blender."**
To not have the option to render alembic files with motion blur or even output motion vector as AOV makes alembic partial useless for a lot of studios.
I don’t know how blender/cycles handle/calculate motion blur, but if its like most other application there should be an option to use an predefined vector (velocity attribute).
I am very thankful for the work that been put into implementing alembic support into blender so far!
Best regard, Valo