Hello there,

I made a fern asset with a looping animation so that I may scatter a few variations in lops. Sadly I can't figure out the usage of the value clip node when using a usd reference.

Using vdbs as in this post https://www.sidefx.com/forum/topic/73648/ [www.sidefx.com] works and also referencing the cache directly as described in another post works for me.

As using the cache works, this is not a blocker for me but using USD assets seems neater so I'm wondering what I'm missing here. If somebody could give me a pointer, I'd be super grateful!

Thanks so much in advance!
seb

There were actually two problems with this setup. First, the solution:
1. Set the valueclip1 "Clip Primitive Path" to "/fern".
2. Set the fern_01 ROP to "flatten all layers" instead of "flatten implicit layers" (you probably also want to change the output file to .usd instead of .usda, or turn of "flush data after each frame" so the ROP doesn't take forever).

The reason for #1 is simply that the primitive paths generated by the fern_01 ROP are rooted at "/fern", not "/fern_01". The second change is the tricky one. Value clip layers are not actually _composed_ by USD. So all of the data that should be applied through the value clip must appear in the single USD file pointed to by the "Clip File or Sequence". With the ROP set to "Flatten Implicit Layers", the fern_01.usda file was empty except for a sublayering of another layer holding the data generated by SOPs. Because clip files aren't composed, this sublayering request is ignored, and USD just saw fern_01.usda with no opinions about the mesh prim. By using "Flatten all layers", the SOP data gets flattened right into the fern_01.usda file, and so the value clip composition sees the mesh attributes and your value clip works as expected.