How do you create groups in an attribute VOP?

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Hi Guys,

I tried searching this one and had no luck. For the life of me I cannot figure out how to create groups of points etc. in the attribute VOP. Would like to know how, then I'd able to replicate what you'd do out in SOPS with the standard group node (but in VOPS)

Thanks - any help would be awesome!
Kind Regards,

Ben
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I don't know how to use the Attribute VOP SOP on its own very well, but in Attribute Wrangle, you can just do something like:

@group_myAwesomeGroup = 1;

My guess is that you need to set up a binding for a group to a variable and set that variable, but I don't know how to do that with a raw Attribute VOP SOP.
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Thanks dude, gives me something to work with
Kind Regards,

Ben
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You could always make a Bind Export and name the export group_myAweseomeGroup.

Alternatively, on the Attribute Bindings Tab you can add an explicit group binding.

Group name: myAwesomeGroup
VEX Parameter: foo

Then do a Bind Export to foo and it will write to myAwesomeGroup. Attribute bindings are the best way to go if you want to dynamically create the group name, like with a chs() expression.

Finally, you can do a Set Attribute VOP with the Attribute Class set to Point Group. This is bests if you want to set a different type of group than you are iterating over, or if you want to set the group membership of points other than the current point.
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Hi Jeff,

What's the equivalent of @group_myAwesomeGroup = 1; for dynamic groups using chs in VEX?

addgroup and newgroup is non-CVEX and setpointgroup is meant to be used to set points in a group other than the current point, right?

Should we use backticks in VEX code?



Cheers.
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Attribute Wrangle also has bindings.

@foo = 1;

and then set the binding of myAwesomeGroup to foo.
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Thanks Jeff, I didn't think of that. Now it's complete
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It seems I was wrong…. Sadly, groups are integer, so @foo = 1 will fail to bind to the group, forcing you to do i@foo = 1.

Bug: 67283 is now present to reflect the fact we should allow float vex variables to bind to groups.
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The Set Attribute VOP has controls for adding points or primitives to groups.
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jlait
It seems I was wrong…. Sadly, groups are integer, so @foo = 1 will fail to bind to the group, forcing you to do i@foo = 1.

Bug: 67283 is now present to reflect the fact we should allow float vex variables to bind to groups.

Thanks Jeff, looking forward to it
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

youtube.com/@pragmaticvfx | patreon.com/animatrix | pragmaticvfx.gumroad.com
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