[Therion] Loop closure

Torsten Schnitter torsten.schnitter at netcologne.de
Sun Jan 6 19:26:26 CET 2013


Hi Martin

Thanks for you answer.

Asume following:
There is a cave with a long tunnel already surveyed.
All the drawings are done so far and you get a nice map.
But the cave is not at it's end at all.
Now you find a new sidepassage somewhere in the middle of the already surveyed
cave connecting back to the maintunnel before the known end. Now you make a loop
closure and get slightly different positions for all stations after the first
connection of the sidetunnel.

OK, for changing the "old" drawings of walls etc I keep the original .xvi file.

1st question:
How do you draw the walls from this new sidetunnel and connect it correctly to
the existing drawings?
Do you work with the old .xvi or the new .xvi file?
Do you use a new scrap and work with joins for the wall drawings?

2nd question:
Now you do more survey at the end of the cave.
In your .th2 file the old walls at there old positions.
But with this loop closure from above the last station of the .xvi (first of the
new survey) is in a different position.
Do you use the new .xvi file and draw the new walls in a new scrap and then
connect them with joins to the old survey?

Thanks a lot for all you help.

Cheers,
Torsten

Martin Sluka <martinsluka at mac.com> hat am 4. Januar 2013 um 18:06 geschrieben:
>
> On Jan 4, 2013, at 2:52 PM, Torsten Schnitter
> <torsten.schnitter at netcologne.de> wrote:
>
> > Hopefully it's clear what my problem is!?
> > So what I'm doing wrong?
>
> Doesn't matter, the exported map will have all parts of your .th2 draw on
> right places.
>
> There is a difference between xvi file - it is always exported from current
> centreline data - and th2 file which is manually drew according a sketch or
> xvi file. If you drew the th2 file on the basis of xvi file and you change the
> centreline data after and you generate new xvi with the same name, your th2
> file will load the new xvi image but it was generated with all changes coming
> from changed centreline. The best way is to preserve xvi file with original
> data on which the original drawing was based. You may compare both xvi files
> (second one with different name) by visibility switch in scrap panel.
>
> But if you generate map based on new data set (with joins] it will include all
> changes (after loop closure) like the new xvi file. You may generate the map
> with layout parameter "debug on" to see your map before morfing and after
> morfing.
>
> m.s.
> _______________________________________________
> Therion mailing list
> Therion at speleo.sk
> http://mailman.speleo.sk/mailman/listinfo/therion



More information about the Therion mailing list