Hi there, I need some animated cloth stiffness and tried to assign a simple attribute build in sop level.

I used this very long expression in the vellumconstraintproperty wrangle slot, inside the vellum sop solver.

stiffness = @var;


I already saw the mastclass stuff without success.
Any advice would be nice. thx


enclosed u`ll find the file

Hi there, I'm new too to vellum so take this with a grain of salt.
I see 2 issues with your workflow:

1) You are trying to read an attribute which is created for the geometry itself.
But you need to work on the constraints actually, so better if you created the attribute for them.

2) You can't use the “@attribute” notation in the constraint properties node to read an animated attribute of the constraint. I guess it's same case as trying to keyframe the constraint parameters at SOP level… Vellum Solver won't read it at ever frame. You need to “import” it with the prim() function.

Have a look at the file.

Thanks for your quick help Andr!