[GRASSLIST:5042] Re: Shaded relief + geology ???

[Thomas Dewez]

John,

Perhaps you may want to have a look at the proceedings of the last 
GRASS conference. I recall reading the papers of some Japanese 
people presenting 3D geological models and methods to get them. 
Proceedings (and most importantly pdfs that go with the 
presentation) are available at:
http://www.ing.unitn.it/~grass/

To compute shaded relief maps, there is a shell script called 
shaded.rel.sh which should do what you're after. You may also 
display other raster coverages with a shaded relief transparent 
overlay so you can see the geological map with a shading figuring 
the relief. This is in the grasstcltk interface under the Raster > 
Display > Display shaded raster map. Supposedly the equivalent 
d.shadedmap command also exists for the command line interface 
but on my home-compiled version of GRASS 5pre5, it is not there. 
In any case, I find that the aspect map used to figure the landscape 
looks somewhat harsh. Instead, I prefer using a slope map for 
rendering the relief.  I am not sure how to fine-tune the range of 
intensities of the "relief-rendering" layer. Does anybody on the list 
know about this?

Does this help at all?

Thomas

> Hi all:
> 
> I am new to GRASS.  I have played a bit with version 4.3 and have
> version 5.0 running on my computer.
> 
> What I would like to do is make a map incorporating geologic raster
> area and shaded relief to come out with a 3-d geologic map.  I have
> brought vector files and dem's into GRASS and have done a bit of
> fiddling around.  In addition I have searched the web and looked at
> tutorial files and man pages.
> 
> But I really am not sure how to even get started.  Can anyone point me
> in the direction of a method or set of procedures?
> 
> John
>