With the new command line I started to draw in TBC.
Is it possible to create my own UCS so I can rotate a drawing, measured in gps coordinates, and rotate it back afterward to world coordinates?
No you can't create a UCS in TBC like to can in Realworks or some other, 3rd party CAD software. You can create a local site however that is more for viewing local grid coordinates which may be different to the false eastings and northings of the underlying coordinate system.
What exactly do you mean by "gps coordinates"? Are you referring to Global Latitude, Longitude and height or are you referring to ECEF coordinates?
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