[GRASS-user] digitize adjacent polygons

Hi,

is there a way to digitize polygons with the new vector digitizer tool, using existing borders? I mean, if I have to digitize two adjacent polygons, how can I start one exactly where the other finishes, using the line shared by the two, without having to digitize it twice?

Thanks,
madi

···

Best regards,

Dr. Margherita DI LEO
Scientific / technical project officer

European Commission - DG JRC
Institute for Environment and Sustainability (IES)
Via Fermi, 2749
I-21027 Ispra (VA) - Italy - TP 261

Tel. +39 0332 78 3600
margherita.di-leo@jrc.ec.europa.eu

Disclaimer: The views expressed are purely those of the writer and may not in any circumstance be regarded as stating an official position of the European Commission.

On 10/03/15 16:35, Margherita Di Leo wrote:

Hi,

is there a way to digitize polygons with the new vector digitizer tool,
using existing borders? I mean, if I have to digitize two adjacent
polygons, how can I start one exactly where the other finishes, using
the line shared by the two, without having to digitize it twice?

AFAIK, you have to break the existing border at the points where the new border will finishes. Then use the "new area" tool and just digitize starting from one of these points and arriving at the other.

Moritz

On Mar 10, 2015 6:02 PM, “Moritz Lennert” <mlennert@club.worldonline.be> wrote:

On 10/03/15 16:35, Margherita Di Leo wrote:

Hi,

is there a way to digitize polygons with the new vector digitizer tool,
using existing borders? I mean, if I have to digitize two adjacent
polygons, how can I start one exactly where the other finishes, using
the line shared by the two, without having to digitize it twice?

AFAIK, you have to break the existing border at the points where the new border will finishes. Then use the “new area” tool and just digitize starting from one of these points and arriving at the other.

… If lacking, please add this to the manual.

Thanks
Markus (traveling)

On 10/03/15 19:18, Markus Neteler wrote:

On Mar 10, 2015 6:02 PM, "Moritz Lennert" <mlennert@club.worldonline.be
<mailto:mlennert@club.worldonline.be>> wrote:
>
> On 10/03/15 16:35, Margherita Di Leo wrote:
>>
>> Hi,
>>
>> is there a way to digitize polygons with the new vector digitizer tool,
>> using existing borders? I mean, if I have to digitize two adjacent
>> polygons, how can I start one exactly where the other finishes, using
>> the line shared by the two, without having to digitize it twice?
>
> AFAIK, you have to break the existing border at the points where the
new border will finishes. Then use the "new area" tool and just digitize
starting from one of these points and arriving at the other.

... If lacking, please add this to the manual.

Done in r64839. Not sure if it is very clear though. Maybe someone could check and then I can backport.

Moritz