Hello all,

I'm trying to use an expression like

$F < $NPT

on the Impulse Activation field of a Source node inside a POP network. But I get an error everytime. -> Cant evaluate expression. In the Impulse Activation field, I get a dropdown and am allowed to pick $NPT from the list. So I'm confused. Should work, shouldnt it? Please help thanks.

I want to generate a particle every frame until I run out of points from the input geometry. My Impulse Birth rate is 1.

Thanks.

activation field should take just 0 or 1, ON or OFF.

weird but not surprising, since that node can accept $NPT, but probably not in activation parameter

just use that expression in Impulse Birth Rate, result will be the same

Thanks Tamte, yes it works on the Impulse Birth Rate.

I thought NPT shouldnt work at all as it is a local variable for a Point SOP?

I'm also having trouble in bringing in a Point attribute created with AttributeCreate SOP into a POP network.
How do I do this?

Thanks again.

$NPT is local variable for many sops and pops, just look at the lelp for Source POP and you will find it there as well

all point attributes are inherited by particles from source geometry by default in Source POP
it's in Attributes tab Inherit Attributes parameter
so you can use it directly in vop pops for example

what you probably want is to access them through the variable like $PARMNAME
in that case check Attributes/Create Local Variables checkbox on Source POP

$F < `npoints(“../pathToIncomingGeometry”)`

or something like that