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storage[edit | edit source]

elevation data stored within Mapbox#Terrain-RGB ... Left: raw RGB, Center: decoded to hypsometric tint, Right: decoded to hillshades

GRASS colors[edit | edit source]

color table ... rules file ($GISBASE/etc/colors/

  • haxby.png haxby
  • bcyr.png bcyr
  • roygbiv.png roygbiv
  • water.png water
  • elevation.png elevation
  • gyr.png gyr

software[edit | edit source]

wikipedia:Terrain cartography[edit | edit source]

GRASS GIS[edit | edit source]

relief shadows resulting from a digital elevation model (DEM) created using the programs 3DEM or GRASS GIS[edit | edit source]

2. illumination coming from the West (270° - from the left), but in cartography the norm has illumination coming from the North-West (upper left corner). This illumination, impossible in reality for the northern hemisphere, has become a convention and in particular avoids the optical illusion of a relief inversion in which one has the impression of seeing valleys as mountains and vice versa
4. change the azimuth to 275°. Change the output filename to Shadows_275, then click on the Run button. Repeat the operation for an illumination from 355°

https://grasswiki.osgeo.org/wiki/Global_datasets#Global_Multi-resolution_Terrain_Elevation_Data_2010_.28GMTED2010.29[edit | edit source]

r.in.gdal 30N000E_20101117_gmted_mea075.tif out=gmted2010_30N000E_20101117
r.colors gmted2010_30N000E_20101117 color=elevation
g.region rast=gmted2010_30N000E_20101117
r.relief input=gmted2010_30N000E_20101117 output=gmted2010_30N000E_20101117.shade
r.shade shade=gmted2010_30N000E_20101117.shade color=gmted2010_30N000E_20101117 \
 output=gmted2010_30N000E_20101117_shaded
d.mon wx0
d.rast gmted2010_30N000E_20101117_shaded
d.grid 1 color=red textcolor=red

3DEM[edit | edit source]

relief shadows resulting from a digital elevation model (DEM) created using the programs 3DEM or GRASS GIS[edit | edit source]

7. modify the colorimetric terrain scale by specifying the colour white for each altitude range, in order to remove topographic information
9. the illumination of the map: by default, 3DEM uses an illumination coming from South West (240° - the bottom left corner), which is natural but in cartography the norm is to have illumination coming from the North West (upper left corner)