RFE: Add groups via VOPs

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I find that I'm frequently doing work with attributes in vops, and then using these attributes in an if statement in a group sop to put some points into a group.

Would this be more efficient if we could create and edit groups directly in vops? My understanding is that it's slower for Houdini to evaluate an hscript if expression than it would be to do the same thing in vops… so it's definitely low priority RFE, but it might be nice to be able to create/edit groups in vops.
Stephen Tucker
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symek@hp2:~$ vcc -X sop | grep group
void addgroup( string; int )
int ingroup( string; int )
void newgroup( string )
void removegroup( string; int )


Is that it?
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It appears to be, but I can't seem to get it to work
Stephen Tucker
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ah, yup, got it working correctly now

I can't really tell if it's more/less/just as efficient during cook time…. so due to the amount of time it takes to set-up, and due to the lack of visual cues as to whether the point is added to the group (no viewport highlighting) It's probably not worth doing it in vops afterall.

But interesting to know that it's possible.
Stephen Tucker
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i user them in popsims, grouping based on expressions is too slow, but with vop it is quite fast
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In vops I tend to use the create_point_group and add_point_to_group (inside an if statement) a lot, especially when the logic is more complex than the evaluation of a single attribute.

*) I also then often use this resulting group as a blast group in a blast sop.
*) If it is only a single attribute I need to check against for blasting I tend to go with the @attributename==1 in the blast sop.
Both these approaches are faster than the delete sop.

There used to be an error when the group you created in vops was named “group”, not sure if it is still there.
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I'm using Point To Group VOP a lot too and I consider it very efficient and not that difficult to setup, it's just one node inside of If.
And if you need visualization you can colour those points in the same VOP maybe through some temporary Visualization switch.


but I've never used Create Point Group VOP, how is it useful except maybe creating empty group? Since Add Point To Group VOP will create the group if it does not exist.
Tomas Slancik
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if You want to use a group, that does not exist, you get a error, so You need at least a empty group
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sanostol
if You want to use a group, that does not exist, you get a error, so You need at least a empty group

I've never encountered this. Add Point to Group VOP, and addgroup() create a point group if needed, at least this is what I observe
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Hey guys, what's the alternative for the Point To Group VOP in H14?
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claudio_101
Hey guys, what's the alternative for the Point To Group VOP in H14?

Can someone please answer this? There seems to be no way to do this now. The addgroup node is still in the help file, but there's no way to get to it and no alternative in VOPS.
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I found this to be very helpful!

https://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=38673&sid=2673cf8d49589dfd39c4c752da4e72e0 [sidefx.com]
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Apparently it's now the addattribute VOP
http://forums.odforce.net/topic/21694-sidefx-releases-houdini-14/?p=129427 [forums.odforce.net]

Would be nice to mention in the help card that the node is deprecated and we should use the addattribute VOP instead.
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Thanks for the link claudio
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