Hello,

I'm working on an Unreal HDA with number of inputs, including a multiparm object merge input for spline paths. I'm running into an issue where each time the HDA cooks or rebuilds, during the cooking process, the network is continuously recooked for each spline input as they are "loaded" into houdini.
In other words, it cooks the network with input 1, then again with input 1 + 2, then again with input 1 + 2 + 3 etc. until all the inputs are in. With more inputs, this makes the HDA take exponentially longer to cook. The only immediate way I found to override this is to go into the houdini session sync, cancel the operations until all the inputs are loaded, then manually render the network - pretty messy.

This seems like a bug, as it should only be cooking once with all of the inputs loaded. From what I can tell it seems specific to the multiparm inputs (each multiparm entry has a world outliner input with a single spline reference). Curious if anyone else has run into this issue or happens to have a solution.

Okay, I found a solution - taking the primitive attribute unique to each entry, promoting it to max as a detail attribute, and adding a switch-if after the multiparm for-each loop to test if that detail attribute is equal to the number of multiparm entries in the HDA.