How to achieve this geometry using Grid SOP?

[magneto]

I am trying to create a vertex at the center of each primitive/polygon, that's connected to each vertex of the primitive/polygon.

Here is a pic to explain it better:

Can I do this using Houdini's built in polygon SOPs? I am using a Grid SOP as a starting point but if there is a better way, please let me know.

[TheUsualAlex]

I was actually hoping that tridivide would do the job, but the "number split" doesn't seemed to be doing it all at once for all primitives. I wondered if this is by design or if this is a bug...

So as a work around, I did this [attachment]. Not ideal for intensive scenario. There are other approaches, but I haven't explore them at the moment.

alexlim_trisplit_v1.hipnc

[magneto]

Thanks Alex, it did the trick. I was expecting to divide a whole grid but this is a good idea too.

Also I am having a problem where I can't see the group I created upstream inside the Copy SOP. Do you know why this might be?

I am basically trying to copy Box objects centered at every point in my group.

[3dbeing]

If you just want boxes at the center of the prim, why not use a forEach?

Here's doing the same thing alex is doing, but inside a forEach so you can use a base grid...

It's hard to understand the question about the groups without knowing the context it's refering, but if you are only trying to copy to the group, it seems the copy sop only accepts primitive groups, not point groups.

forEach.hipnc

Edited December 27, 2011 by 3dbeing

[zarti]

here it is another way ,

Polyextrude with Scale parameter set to 0 .

you can benefit from this SOP options to :

save original grid , add divisions , etc . .

centerConnectedz.hipnc

[magneto]

@3dbeing: I didn't know Copy SOP didn't accept point groups.

As for why I was doing it is because, I am trying to make a very basic Paint SOP experiment where I want to paint on the center of a polygon, and put a Box SOP at each painted primitive. It seemed like Paint SOP only paints on points and painting on points isn't good for me, as the potential user of this tool will want to paint at the center of the primitives/polygons to populate them with Box SOPs. That's why I thought of splitting them like this so that the user can still think of them as whole polygons that they are painting.

Thanks for the example scenes, will be checking them now.