Solver killing alembic animation

[FurFX]

Hi Guys!

when I input an alembic file into a solver input, I lose the animation after the fact. Is this a known issue between alembic and the solver node? or am I missing something? (more likely)

[bandini]

The solver records the first frame. You have to update the animation yourself in the solver. Otherwise, it is only going to show the first frame and nothing else will happen.

[FurFX]

Thanks so much for your reply dude!

so to update the anim INSIDE of the solver, is that a matter of bringing the alembic importer inside the solver? or is there a way to update the animation from the outside alembic node INSIDE of the solver node?

[FurFX]

11 hours ago, bandini said:

The solver records the first frame. You have to update the animation yourself in the solver. Otherwise, it is only going to show the first frame and nothing else will happen.

any ideas how to update the alembic INSIDE of the solver?????????

[bandini]

The solver gives you feedback from the last time step. You also have inputs that show the current time step. You can decide what attributes you need to copy back to your geometry. If you are working with packed alembics, there are a bunch of things you can copy. Position and some of the primitive instrinsics should be copied and updated each frame. There's a bunch of transform data stored in primitive intrinsics. Do a search here for primitive intrinsics and you'll find a lot of info.

[FurFX]

2 hours ago, bandini said:

The solver gives you feedback from the last time step. You also have inputs that show the current time step. You can decide what attributes you need to copy back to your geometry. If you are working with packed alembics, there are a bunch of things you can copy. Position and some of the primitive instrinsics should be copied and updated each frame. There's a bunch of transform data stored in primitive intrinsics. Do a search here for primitive intrinsics and you'll find a lot of info.

I think I may have worded this confusingly. What I mean to say is, how do you retain deforming geo within the SOP solver while still respecting the last frame time offset it offers?

[bandini]

Same answer. Copy the position information from Input 1 to the solved object. Attribute copy, attribute wrangle, attribute vop... A bunch of different ways to do it.

[bandini]

If geo is packed, unpack it first so you have access to the deformed points.

[FurFX]

55 minutes ago, bandini said:

If geo is packed, unpack it first so you have access to the deformed points.

Thanks man, I really appreciate it. I had an alembic cache of a human, and I needed the points to freeze once a gradient on the surface reached a value above 0. Transferring the P attribute from the First output to the PrevFrame did it. Thanks man!