Diving inside the network i can see the rop fbx responsible for exporting the low res fbx geo.

I am trying to do the same thing in an other setup but i cant figure out how does it get triggered.

Usually you have to press the Save button or build a TOP network. i dont see any TOP networks inside the HDA

Is this magic?

it's trigered from the Python code in HDA's python module that's called from the callback script on Render button
but more specifically it's this particular line

tamte
it's trigered from the Python code in HDA's python module that's called from the callback script on Render button
but more specifically it's this particular line

a_node.node("low_export").render()

ohh yes thank you! no way I would find that.

Also i tried to modify that fbx rop to build a hierarchy from path , i added a few extra parameters after the fbx path in the type properties, but when i saved the hda a warning popped up about possibly breaking some internal references. After that the hda wouldn't bake the maps from the cop network inside.

Any idea why would that happen? Its weird because it was just a minor change and had nothing to do with baking the maps as far as i can see