Hi,

We occasionally run into issues, where Solaris decides to write out parts of the script as it's own USD files. It could be a subnet including multiple sopcreate nodes or a range of Light nodes.

Is there a way to always flatten these layers created in the script and avoid Solaris trying to write out temp USD files for different parts of the script? And what is the logic behind when it's including everything in the main USD we write out and when it's trying to split out the layers.

We have the main USD rop node set to "Flatten Implicit Layers" and we don't have any Layer Save Path's defined anywhere in the script.

This can happen for a variety of reasons... If you put a "from disk" sublayer or an "import from sops" layer between two lop-authored layers, Houdini will separate the "before" and "after" layers into two separate layers to precisely preserve the opinion strengths of the various layers. If you use the secondary inputs of the Reference or Sublayer LOP, the data connected to the secondary inputs will be written out to separate layers (because otherwise the structure of the USD that is saved will not match what you have specified in the LOP network).

Those are some of the common situations that can force the USD ROP to write out multiple USD files, but there may be others I'm not thinking of right now. I'd have to see the LOP Network to know for sure what is triggering these separate layers to be created.

Hi Mark,

Thanks for your reply.

It seems the writing out of the layer USD files is necessary to keep the structure intact.
Is there a way to override the layer save path syntax for everything in a hip? It seems to default to $HIP/primPath/OUT.USD

Not without writing some code. You could write an output processor that recognizes our standard auto-naming, and changes it to whatever you want. Other than that you have to set the save path on each layer.