I know this isn't really a GPS thing but I know many on this
mailing list like to tramp around off the beaten path. To that end,
I've just posted a program to GitHub that allows you to automatically
cache data for Google Earth so that you can load it and use it offline.
The reason I wrote it is that I couldn't find a caching program for
Linux. The program is called geCache, I've released it under GPLv3, and
it compiles, links, and runs on Linux and Windows 10 (I didn't try it on
7). It's written in C++ using Qt5.
It has a couple of nice features. You can define a rectangle or
polygon in Google Earth by using Ctrl-Shift-C to put positions into the
clipboard. geCache will place the positions into either a rectangular
boundary or a list of polygon vertices. You can edit the rectangular or
polygonal bounds after you have defined them (again, using Ctrl-Shift-C
in Google Earth). You can save and load multiple caches. Also, if the
cache becomes too full it will prompt you to save that as a single cache
and then continue caching data.