[2.1.9] surface_vertical_offset makes planet images get cropped

[thesixthroc]

I am relaying this request from my collaborator.

Increasing the parameter surface_vertical_offset makes more room for the atmosphere, but it does this by cropping the planet, which causes glitchy-looking graphics that seem like a bug (especially as the planet rotates).

A preferred behavior would be increasing surface_vertical_offset to shrink the overall size of the surface rather than crop it.