[Therion] Extended elevations with survex data

[John Pybus]

Stacho Mudrak wrote:
> The problem, that therion exteded elevation was not designed to be used 
> with extended 3d files import. You should be able to control xelevation 
> using extend switch in centerline. Could you please try following:
> 
> survey texa-elev
> 
>     import texa_extend.3d
> 
>     centerline
>       extend start 3 # start extended elevation from station 3
>       extend right 5 # from station 5 - extend to the right
>     endcenterline
> 
>     input elev_top.th2
> 
> endsurvey
> 
> May be, you will have to add @subsurvey.survey to station names in 
> extend command or use -surveys ignore switch in import command. For some 
> details, see:

That seems to have done the trick.

Thanks!

John