[GRASS-user] Very high resolution topographic map of Europe: need help and advices: UPDATE

[achim]

Very nice!

> b - The big problem are coastlines and waterbodies (+main rivers):
> somehow I have to show them on the topographic map, which gdalwarp has
> filled out with -32768 values in nodata-waterzones. So either I cut
> waterbodies out of the topographic raster along the vectors, or I
> somehow have GRASS compute me all waterbodies from the vector layer,
When I understand right, its easy. In case of having all vectors as
polygons, try "v.to.rast". Then you have a raster layer of desired
resolution (set with g.region).
> fill them with a nice blue and create a raster which can be pasted
> over the topographic raster to get the final map.  It seems doable
> with mapcalc, but frankly, I do not know at all how to proceed. Any
> help here would be greatly appreciated.
When you want to overlay the topographic-map with water-information, be
aware what you want to do: when you just want the information, that
there is water, you are done with telling the new raster-layer to be
blue and transparent.
If you want to change the topology for calculation with r.watershed
(e.g. river-burning) or flatten lake-regions or set topography on
coast-lines to zero, it would be a bit more to do.

Cheers,
Achim