Is there a way to increase the number of particles for the source without reseed on Flip SOP, I could do that with the DOP workflow adding a custom source particles regardless of particle separation.
Any tips?

FLIP Solver SOP is always reseeding sources since they come in as SDF so it has to generate points no matter what

therefore, it will still use Reseeding settings even with reseeding off

so you can for example set surface oversampling to 3 and then uncheck reseeding, you wil notice that the source is still oversampled

Thanks for the feedback!

Is there a way to keep it oversampled just on the first frame and keep the point count?
It would be spurcing just on the first frame.

I am asking this because I am noticing in this new SOP point count change even when reseed is turned off and I am just emitting on the first frame, is that normal?

mzigaib
Thanks for the feedback!

Is there a way to keep it oversampled just on the first frame and keep the point count?
It would be spurcing just on the first frame.

I am asking this because I am noticing in this new SOP point count change even when reseed is turned off and I am just emitting on the first frame, is that normal?

if Reseeding and of course Narrow Band is off and you are not sourcing anything anymore then Reseeding should not kick in

Do you have an example?

I am having the same issue; only emitting on the first frame, but more points are added. Hip file is attached. My setup:

Flip Container -> Flip Boundary -> Flip Collide -> Flip Solver. A small box as Geometry to Source (plugged into the flipboundary), a bigger extruded box as collision geometry (plugged into flipcollide). Flip Boundary Activation: $FF==1. Flip solver settings: Narrow Particle Band and Reseeding is off.

If I have a Particle separation of 0.03 on the Flip Container (roughly 130K points) the point count is stable. But if I go to 0.02 (400K points), the point count increases with every frame. I have experimented with substeps, "Enforce Particle Separation" (on the Flip solver), size of collision geometry etc.

Any thoughts/explanations would be appreciated!

In your case I think if you turn off reseed and narrow band should work.

But trying to keep the resolution and just increase the number of particles on the first frame in this flip SOP workflow it is still a issue for me, I also did not find a reliable way to add id attribute.

Trying to use the reseed to oversample even with narrow band turned off increases particles overtime, I could do that with DOP workflow increasing just the number of particles but keep the same resolution.

I really like the this SOP workflow I just wish to have more control without too much tinkering.

Any tip would be welcome.

Here is an example comparing DOP and SOP workflow.

mzigaib
Here is an example comparing DOP and SOP workflow.

you forgot to uncheck Reseeding

as mentioned above [www.sidefx.com] if you want to oversample just sources, you can modify oversampling parameters , but then turn off Reseeding again so that only sources are seeded and not the sim

Thanks for the feedback!

Oh I got it, I did not know that I need to turn it off again, I will try that.

Cheers!