On Thu, Apr 19, 2012 at 6:17 PM, Markus Neteler <nete...@osgeo.org> wrote: > Hi all, > > does anyone have a new(er) trick for negative vector buffers (in GRASS 7)?
Internal buffers of areas are now (r51573) supported in trunk with negative distances if GEOS support is enabled, i.e. v.buffer distance=-1000 type=area works. Markus M > > thanks > Markus > > On Thu, Oct 29, 2009 at 4:59 PM, Milton Cezar Ribeiro > <miltinho.astrona...@gmail.com> wrote: >> Hi Maning, >> >> Sometimes I have the same issue, but I don't solve this on vector. >> Just supose you have a map where 1 is your raster-based-polygon >> and NULL is outside of polygon. You can use r.mapcalc to >> invert it, in the maner that 1 come to be your non-polygon, and >> NULL your polygon. So you can run r.buffer with positive value >> and at the end may be you need to do some kind of crossing >> between original and output maps. >> >> Bests. >> >> miltinho >> >> 2009/10/29 maning sambale <emmanuel.samb...@gmail.com> >>> >>> I tried using a negative values as >>> buffer=-3000 in v.buffer but it doesn't give me internal buffer in a >>> polygon layer. >>> >>> Any hints? >>> >>> -- >>> cheers, >>> maning >>> ------------------------------------------------------ >>> "Freedom is still the most radical idea of all" -N.Branden >>> wiki: http://esambale.wikispaces.com/ >>> blog: http://epsg4253.wordpress.com/ >>> ------------------------------------------------------ >>> _______________________________________________ >>> grass-user mailing list >>> grass-user@lists.osgeo.org >>> http://lists.osgeo.org/mailman/listinfo/grass-user >> >> >> >> _______________________________________________ >> grass-user mailing list >> grass-user@lists.osgeo.org >> http://lists.osgeo.org/mailman/listinfo/grass-user >> > _______________________________________________ > grass-user mailing list > grass-user@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-user _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user