That does make sense also, switching the crop parameters to be part of the texturing section of 3D objects.

I think it would be better overall if scenes were typed as capture sources instead of as layers.

Exactly. I crop the content in the virtual camera (from OBS) into 36 parts and put each into an individual screen. It would be nice to do it all in Polypop. I'm doing it so I can switch out the content being displayed and only go through creating 36 crops one time.