Working with grains, I'm trying to use “Enable Rigid Shape Matching” (enablerigids on mouseover) on a partial mesh but I've been unsuccessful so far.
The docs doesn't even cover if it's a point or primitive attribute but when experimenting, trying both, nothing seems to produce any change in the sim.

Any insight on this? Thanks!

Enable Rigid Shape Matching checkbox is not directly controlable by an attribute, it's just a switch

but you can add primitive attribute called isrigid to your constraint geometry to control rigidity of the constraints if you have that switch enabled

so if that attribute is present and Enable Rigid Shape Matching is enabled, each connected island of constraints marked @isrigid=1 will be treated as rigid and @isrigid=0 will stay as “soft” constraints

That did the trick, thanks Tamte.
Where do you find info about this though?
I can't find anything about the isrigid attribute in the docs of even on google.

Mattias Magito2
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Where do you find info about this though?….

I looked inside of POP Grains node and was lucky enough to find it in there

Thank you Tomas, wished they added that to the help docs