[GRASS-user] Help with creating bathymetric maps

[Alyre]

Hello,

I am trying to create a bathymetric map of a small pond. I have imported the
depths and  digitized the outline of the shore (0 depth contour). I believe
in GRASS both would by default be in vector format and I need to transform
them into raster and merge both files. I have successfully converted the
shoreline into raster form but it appears as a solid area as if the whole
polygon that enclosed the pond was transformed and not the outline. What I
need is to convert the outline of the polygon to a series of raster points
and be able to define the spacing. The spacing of the 0 contour points
appears to me to be important as it will influence the interpolation of the
contours when the transect depths are added. In addition I am not sure how
to assign the additional attribute of depth (which would be zero) in the
transformation process or how to add it afterwards. From what I understand
in GRASS, points are actually vectors but to do contours everything has to
be in raster format. So I assume I will have to convert the depths (x,y,z)
into raster format as well then merge the two raster files (shore outline of
zero depth with depth transects). 

I assume GRASS is widely used to do bathymetric maps, a bit like elevation
contours but with negative values. If anyone knows of a tutorial or step by
step guidance at a beginner's level that would be most helpful. The
bathymetric map is only a support element of a large fish distribution study
but is turning out to be much more difficult to achieve than expected.

Thanks

Alyre
-- 
View this message in context: http://n2.nabble.com/Help-with-creating-bathymetric-maps-tp2896653p2896653.html
Sent from the Grass - Users mailing list archive at Nabble.com.