unwrapping based on actual mapping projections

Hello, I have an interesting question for everyone. Typically, you unwrap a mesh first, then export the UV map, then photoshop an image onto said map. But what if you want to do it in the reverse order? What if you already have a photoshoped UV map image and you would like to create seams on your mesh so that they match up with the map?

I have a mapping program that takes typical flat, Mercator maps and transform them into other projections that may be more ideal for wrapping them around a globe. Is there a keen trick to create seams in the right places, or has someone heard of a plugin or something that unwraps spheres based on actual mapping projection schemes?

All of the tutorials I’ve seen for texturing Earth do not involve unwrapping - but my project requires an Earth model that has been unwrapped/uv mapped.

I hope that makes sense… Thanks in advance!


Well, found an alternative to what I was trying to achieve - so I’m good now.