Hi,

I have a vellum hair sim setup using the usual Guide Groom, Guide Deform, Guide Simulate chain of nodes.

I'm taking the Guide Deform output and Guide Sim output and blendshaping between selected curves user defined by a group for cleaning up curves that are getting stuck in a collider etc. Basically, this allows the user to blend back specified curves from sim shape to guide deform (static) shape.

This all looks good in Houdini, but when I export via a ROP Alembic, the blended curves shoot off in the alembic. If I blend all curves, the output looks correct, but this setup where I am blending only selected curves, looks correct in Houdini, but the output alembic is wrong.

I can't post a file or image right now, but here is a description of the nodes:

object merge: guideDeform/OUT_ANIMGUIDES
object merge: Vellum Solver Curves

both go into group nodes set to primitive, where the user can select the curves to blend.(both groups are identical in name and base group contents).

These groups go into a blendshape node with the group specified so only those curves are blended. (I have alternately tried point node and point wrangle to do the blend, with the same correct look in Houdini, incorrect in output alembic)

This blend is then going to a transform node to scale and orient object for other DCC package, then out to the ROP alembic.

I'm not sure if something is causing double transforms, but the blended curves shoot off from where they should. Is there some attribute on the curve that would cause this?

Help.

Thanks,

Adnan