Hello,

The topic itself explains the problem pretty clearly I think, but just to make it clear - I am doing a grain sim using pop (not vellum. Particles/grains start disabled/stopped (set the stopped attr to 1 before sourcing them to dopnet)and they are activated by a mask inside dopnet using sop solver.
Later I decided to enable particle sleeping via pop solver for efficiency reasons (so the particles get disabled/stopped when they stop moving). Although I noticed particles keeps jumping between "stopped" attribute values of 0 and 1, but no matter if it 0 or 1 they still keep moving. How come?


Video demonstrating the problem attached below.
I have isolated just a single particle so it's clearly visible:

Thank you

Found out that it all works just fine if I disable SOP solver (that transfers Cd attribute/mask from outside of dopnet which is responsible for making particles "active").
So now the question is - how do I activate my particles with a growing/spreading mask, but also make use of "particle sleeping" feature?

mantas_kava
Found out that it all works just fine if I disable SOP solver (that transfers Cd attribute/mask from outside of dopnet which is responsible for making particles "active").
So now the question is - how do I activate my particles with a growing/spreading mask, but also make use of "particle sleeping" feature?

you can introduce another attribute, like i@activated
and have your spreading mask logic work only on particles with group: @activated=0

and have it set
i@stopped = 0;
i@activated = 1;

it will never be run for the already activated ones ever again regardless of whether they become i@stopped=1 in the future

That sounds like a plan, tamte. I'll try that out, thank you!