I am currently working on a project where we have to figure out the position of one point based on the known position of two (user-input) points.
Now the problem is that the users could provide two points in different UTM zones, so we have to project one of the points to the other system (at least that is how we do it.)
I coded a reference implementation in Python to test it, and now we want to use this feature in production on iOS. It seems as if the only swift proj library here is out of date and can not be used.
We looked around for a bit, but did not find a description of how to project a point from one zone to the other one without additional software.
Do you know whether this is possible, or whether there is an up-to-date proj library for swift?