DESCRIPTION
v.out.ogr converts GRASS vector data to
OGR format.
OGR (Simple Features Library) is part of the
GDAL library, so you need to
install gdal to use v.out.ogr.
Supported OGR Vector Formats
ESRI Shapefile
CSV
GML
KML
Mapinfo File
PostgreSQL/PostGIS
TIGER
For further available drivers go
here.
NOTES
To export areas with holes into, e.g., a Shapefile, while keeping the
holes as holes, the flag -c has to be used.
EXAMPLES
Export to Shapefile
Export lines from GRASS vector map to Shapefile format
(generates /tmp/testogr.shp and related files):
v.out.ogr input=multi type=line dsn=/tmp olayer=testogr
Export areas from GRASS vector map to Shapefile format, preserving islands
(generates /tmp/testogr.shp and related files):
v.out.ogr -c input=multi type=area dsn=/tmp olayer=testogr
Export 3D lines from GRASS vector map to Shapefile format
(use SHPT=POLYGONZ for 3D faces):
v.out.ogr input=lines_3d type=line dsn=/tmp olayer=testogr lco="SHPT=ARCZ"
Export to GML
Export lines from GRASS vector map to GML format
(generates /tmp/testogr.gml file with layer 'testogr'):
v.out.ogr input=multi type=line dsn=/tmp/testogr.gml olayer=testogr format=GML
Export to PostgreSQL/PostGIS
Export areas from GRASS vector map directly to PostGIS:
v.out.ogr input=polygons type=area \
dsn="PG:host=localhost dbname=postgis user=postgres" \
olayer=polymap format=PostgreSQL
Export to KML (Google Earth)
Example 1 (Latitude-Longitude location):
Export faces (3D vectors) from GRASS vector map to KML format for Google Earth:
v.out.ogr input=buildings_3d dsn=buildings_3d.kml olayer=buildings_3d \
format=KML type=face
Example 2 (Latitude-Longitude location):
Generate and export GRASS vector "asteroid" map (faces, 3D vectors) to
KML format for Google Earth:
# near Raleigh (NC, USA)
g.region n=35.73952587 s=35.73279182 w=-78.68263928 e=-78.67499517
# two layers of random points
v.random -z output=random3d_a n=10 zmin=0 zmax=200
v.random -z output=random3d_b n=15 zmin=400 zmax=600
# merge into one 3D points map
v.patch input=random3d_a,random3d_b output=random3d
# generate 3D convex hull
v.hull input=random3d output="random3d_hull"
# export to KML 3D
v.out.ogr input=random3d_hull dsn=random3d_hull.kml format=KML \
type=face dsco="AltitudeMode=absolute"
# now open KML file 'random3d_hull.kml' in Google Earth or NASA WorldWind or ...
REFERENCES
OGR vector library
OGR vector library C API
documentation
SEE ALSO
db.out.ogr,
v.external,
v.in.ogr
AUTHORS
Radim Blazek, ITC-Irst, Trento, Italy
Some contributions: Markus Neteler, Martin Landa
Last changed: $Date$