I have a piece of geometry containing several groups of primitives. In a Shader SOP, I try to apply a shader to particular groups, selecting them from the list, but then I get a yellow arrow warning saying the group is invalid.

I went through in another program and meticulously made sure that there were no shared primitives in the groups. One thing I notice is that there are vertices and points in the geometry rather than all vertices or all points. I don't know if that's what's causing the problem.

I've had this problem several times in different versions of Houdini with delete SOPS and group SOPS. But don't see this recorded in any other posts.

Does anyone know what the problem is?

Thanks,
Christine

Running H7.0.381 on XP

i`m not sure what causes it, but if you create the group in the viewport, first by

tab>group > select a primitive > reselect geometry and select what you want > right mouse.

it seems to fix it.. initialising groups in the network editor seems to have a bug.

I have groups already saved in a bgeo file. It's a complex model with many groups. But if I try to delete all but a single group or try to apply shaders to groups, it says “Invalid group”.

Have you tried saving it out as a .geo (ascii) file and then loading it that? I can't remember now but I recall seeing at one point munged .bgeo files that had a trailing space in their group names.

That was it. There were some invisible characters in the group names. Houdini Support said the same thing.

Thanks!
Christine