questions about GRASS

[Evaristo QUIROGA]

<
< Dear Sirs, 
< I'm a new GRASS user, I've just started using it in a Linux environment.
< I have some questions for you. The first one is: how can one import raster
< files output from scanners (i.e. in such formats as TIFF, RLC and so on) ?
< The second questions is: how can one import 3-d DXF files (I mean, XYZ data) 
?
< And finally, how can I get the RIM software package ?
< I'd greatly appreciate any suggestions on the above.
< Gratefully,
< Michele Carta
< 
< Address:
< via della Potara 28
< 36015 Schio (VI)
< Italy

        Dear Michele,

First, you can import a raster file output from scanners with the raster
import commands : r.in.tiff, r.in.gif, r.in.ppm or r.in.sunrast. Later you
will want to use this image in real coordinates, for this you have to register
it. For this look the Jim Hinthorne comments posted the 15 Feb 1995:

-  Get the GRASS Image Processing Tutorial from the moon server, and pay close 
-  attention to the section on rectification/georeferencing. If you have a lot 
-  of control points, i.rectify2 does a very nice job, otherwise use i.rectify.
-
-  The general sequence of events is:
-  1. start grass4.1 and create or verify that you have a mapset in the 
-   location with the desired final coordinates. exit grass.
-  2. start grass4.1 and create or use a location with an x-y coordinate system
.
-  3. import the images into the cell directory in this x-y mapset.
-  4. build header files using r.support and be sure the images display ok.
-  5. run i.group and put your "co-registered" bands into a group.
-  6. run i.target and specify the destination location and mapset--must be on 
-   same disk as x-y location.
-  7. run i.points and specify the control points (this can take much time and 
-   reading of manual pages and tutorial.
-  8. run i.rectify or i.rectify2
-  9. exit grass and reenter grass4.1 in the destination location and mapset 
-   and check the quality of the registration.



Second question: If you want import the Z coordinates of POLYLINEs (contour
and isolines types) of 3d-DXF files, you can run the program "v.in.dxf3d" in
conjunction with "v.in.dxf" and "v.support". I have put this program to the
"moon" server the last month.


Finally, the RIM package is in the "src.related" directory of the grass 
source distribution.


                Bye.
                                        Evaristo.

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      / /          Evaristo QUIROGA RAIMUNDEZ                 / /
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/    /          UNIVERSIDAD AUTONOMA DE BARCELONA       /    /
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