Does KtoA pick up velocity attributes for instances?

[t.voll]

We're attempting to get motion blur working with point instancing. Is KtoA setup to use velocity? The instances contain velocity information (in the geometry.arbitrary.v attribute). We've tried using the velocityApply node.

The issue could be on our end but we just wanted to verify that this should work before going further with other attempts.

[Mike_Farnsworth · Accepted solution]

Yes, it should. I have an example of point-instancing with velocity motion blur which uses a opscript to randomly generate one velocity vector for each point. The velocities are stored in geometry.point.v, and then it uses the VelocityApply node to turn geometry.point.v into actual motion samples on geometry.point.P.

KtoA will not apply the velocity itself, but requires the VelocityApply node in Katana to take care of that. This is true for other vertex/point velocities as well, such as sim geometry where the topology changes per frame, and all you get is a per-vertex velocity.

Unfortunately, I can't attach a .katana file to an answer, so I will email you an example.

[t.voll]

Awesome! Thanks for the Eureka moment.