[GRASS-dev] [bug #2793] (grass) v.segment: side offset is ignored

Hamish hamish_nospam at yahoo.com
Fri May 4 01:54:49 EDT 2007


Markus Neteler wrote:
> > > > > https://intevation.de/rt/webrt?serial_num=2793
..
> > now functional in CVS.
..
> > Backport to 6.2 or comment out references to offset in the help
> > page?
> 
> +1 for backport.

done.

 
> > > > shift offset to the left or right?
Markus:
> At least it should be consistent within GRASS.

I have now changed it to match Vect_line_parallel(). Positive side-
offsets now go to the right side of the line.


> > > can anyone compose a nice example (x2) for the v.segment help
> > > page?

Markus did this, and just now I've added a little more.


Markus:
> BTW: v.lrs.segment suffers from the same problem:
> http://grass.itc.it/grass63/manuals/html63_user/v.lrs.segment.html
> P <pid> <lid> <milepost>+<offset> [<side offset>]
> L <sid> <lid> <milepost>+<offset> <milepost>+<offset> [<side offset>]

Yes, code is mostly cloned so it would be easy to copy & paste in the
same solution.


BUG: (adding to the tracker)
There is a problem with side-offset parallel line generation for inside
corners. It is in Vect_line_parallel(), so v.parallel et al. are also
affected. See it by doing the "-500" side-offset example in the
v.segment help page and changing -500 to +500. Or "v.parallel dist=500"
using the railroads vector map.



Hamish




More information about the grass-dev mailing list