Fix upright handling

A small bug basically disabled the upright option scale factor handling by
comparing an object (opts.upright) with 0. As a result, the default factor of
0.75 was always applied instead.

This patch makes sure that the upright scale value is properly referenced with
opts.upright.v.

Change-Id: I28fabfb4e5384c262d9daf47a165a50744c22151