Mmmm feeling a bit silly but can't get an expected behaviour and not sure why. Without going down the component builder hda route, I want to in the simplest way possible create a payloadable usd asset, with bounding box preview.
Using Houdini 19.5 (at work)
I have a model.usd and material.usd file, that I am sublayering together and write out as an asset.usd
When I use a reference LOP to bring in my asset.usd, and set node to payload, the asset unloads. As expected there is no bbox preview. All info about this points to using a node called loftpayloadinfo to generate bound info.
When I append this node below model and material sublayering, write out my asset, reference it back in... Same result. Also I do not see any bbox metadata in the usd file. The node did nothing.
However using that new reference node, if I set it to payload, and append a loftpayload below this, I now see a bbox (strangely being created from an asset not loaded?!)
If I write this out as payload.usd, and I once more reference in this new file, with it set to either "reference" or "payload" in the reference type field, I get payload behaviour with bbox! Is that correct? (perhaps that's how it means to be? i.e i'm referencing a payload now so it's behaving like one?). Seems a bit confusing I can no longer choose load behaviour as reference, or payload, on the node that behaving exactly like that in just the previous step.
If that all sounds correct, How can I set up the bound info directly when i'm sublayering my model and lookdev together to prepare my asset.usd? I suspect it want's a root prim to write the metadata to that wont be there with I reference, so that's why it doesn't work?
Interestingly to help demonstrate, at home (H20.5) ive tried to add an example file to showcase my confusion. However there i hit another issue. If I set any reference to payload, its doesn't change to one. That sounds broken. (file attached)