Common Tasks

Mini-tutorials showcasing some common GIS taks

Import/Export and Display

• Import and display SRTM elevation data

r.in.srtm

• GRASS Newsletter, 3, June 2005.
• You can also get the SRTM data with a convenient web interface at http://srtm.csi.cgiar.org/. These come in 5 degree blocks and can be downloaded either as geotiff or ascii files.

• Import and display VMap0 Digital Chart of the World

v.in.ogr

• GRASS Newsletter, 3, June 2005.
• If your region crosses the boundaries of a VMap0 block you can use the v.append command, available in the Grass addons section of this wiki, to combine vectors across the edges. It can take quite a while to complete.

• Import and display ETOPO2 world elevation and bathymetry dataset

r.in.bin

• Global dataset of bathymetry and topography. GRASS Newsletter, 1:8-11, August 2004.

• General raster import and export with r.in.gdal / r.out.gdal

• r.in.gdal misc. tips
• r.out.gdal data types, creation options, new flags

• General vector import and export with v.in.org / v.out.ogr

• v.in.ogr misc. tips, shapefile gotchas
• v.out.ogr data types, dsn, new flags

GIS Tasks

• Georectify a scanned raster image
  • r.in.gdal into XY location
  • GUI georectifier
  • i.points + i.rectify (alternate method)

• Trace vector contours from a scanned map

• Create a DEM from contour lines and trig points
  • r.surf.contour

• Create a DEM from x,y,z point data
  • v.surf.rst
  • v.surf.idw
  • v.surf.bspline
  • r.surf.nnbathy

• Create vector contour lines from a raster DEM
  • r.contour

3D Visualization

• Use NVIZ to render a 3D image

nviz elevation.dem

• Use NVIZ to make a fly through movie
  • see nviz keyframe animation panel help page
  • Encoding Movies

• Use Paraview to render a 3D image
  • r.out.vtk, v.out.vtk

Raster operations

• Create a shaded relief map
  • r.shaded relief

• drape semi-transparent land use map over shaded relief map
  • d.his

Vector operations

• Disolve interior lines
  • v.dissolve

Hardcopy and Presention Graphics Creation

• Create a high quality hardcopy plot
  • Creating PostScript with ps.map
  • export to GMT