[GRASS-dev] [GRASS GIS] #3646: v.external.out and r.to.vect support

[GRASS GIS]

#3646: v.external.out and r.to.vect support
----------------------------+-------------------------
 Reporter:  neteler         |      Owner:  grass-dev@…
     Type:  defect          |     Status:  new
 Priority:  normal          |  Milestone:  7.6.0
Component:  Vector          |    Version:  svn-trunk
 Keywords:  v.external.out  |        CPU:  Unspecified
 Platform:  Unspecified     |
----------------------------+-------------------------
 Running
 {{{
 ##  Test case for nc_spm_08_grass7:

 # test GeoTIFF preparation:
 r.out.gdal input=landclass96 output=landclass96.tif
 createopt="COMPRESS=LZW"

 # register GeoTIFF
 r.external input=landclass96.tif output=TMP --o

 # define external vector file, here GeoPackage
 v.external.out output=landclass96map.gpkg format=GPKG

 # rasterize LULC map, write out directly as GPKG
 g.region raster=TMP -p
 r.to.vect input=TMP output=landclass96map type=area column=landuse

 # cease connection
 v.external.out -r
 }}}

 leads to:

 {{{
 r.to.vect input=TMP output=landclass96map type=area column=landuse --o
 Extracting areas...
  100%
 Writing areas...
  100%
 Registering primitives...
 Building areas...
  100%
 Attaching islands...
  100%
 Attaching centroids...
  100%
 Copying features...
 WARNING: Boundary is not closed. Feature skipped.
 WARNING: Unable to write feature in vector map <landclass96map>
 WARNING: Writing new feature failed
 Exporting areas...
  100%
 WARNING: Copying features failed
 r.to.vect complete.
 }}}

 From https://lists.osgeo.org/pipermail/grass-
 dev/2018-September/089719.html:
 "topological areas can only be converted to non-topological polygons after
 all boundaries and centroids have been written out and after topology has
 been built."

 This would be quite useful in order to write such scripts as Python jobs
 (think "grass-session").

-- 
Ticket URL: <https://trac.osgeo.org/grass/ticket/3646>
GRASS GIS <https://grass.osgeo.org>