Hi, me and my friend developed an add-on that unwraps UVs based on model curvature.
Currently it works best on hard-surface models, organics perform a bit worse, as there are usually mostly gentle curvature changes.
Of course, there is no substitute for hand-made UVs, but it will give a decent starting point, or will help with objects in the background.
It works well regardless of topology, so even if you have something auto-reduced, it would perform almost identically.
It’s pretty fast, unwrapping 330k mesh in 3.7 seconds on a 12-core CPU.
Here’s the link to the add-on itself:
https://superhivemarket.com/products/okunwrap
If you have any feedback - I’d greatly appreciate it, since it’s a 1.0.0 version, so there is room for improvement. Thanks!
And here are unedited examples of UVs it produces on different objects:
High resolution images on Imgur
Bike
Bionic Arm
Chair