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BenS-3
 I am a new GRASS user trying to bring a DXF (Autocad) file into GRASS. The
 DXF file has elevation values associated with the points as well as an
 entity type 3DLINE.  According to the reference manual Grass only
 recognizes points, lines, polylines and text in DXF format (v.in.dxf).  My
 objective is to view the image as 3-d.  I can manipulate the file to get
 Grass to display the image, but it is flat.  I have looked at d.3d in
 Grass, but I lack a raster map with elevation category values.
 
 Question:
   1.  Does anyone have a newer v.in.dxf program that will accept and store
       elevation values for later use.?
   2.  Does anyone have any ideas on how to relate the elevation values
       from the DXF file to a grass vector or raster image?
     
Thanks.
Jan Benson at [hidden email]


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Re: DXF import

Melissa Records
From: Jan Benson at [hidden email]

>  Question:
>    1.  Does anyone have a newer v.in.dxf program that will accept and store
>        elevation values for later use.?

The current "v.in.dxf" program can import text elevation values, but
not Z values.  This capability has proved most useful in importing
contour files into GRASS.  So, let's say you've got a contour file
with elevation text on the index contours.  The way that CAD data is
usually formatted, the contour lines are on one level and the text is
on another.  The "v.in.dxf" program creates a dig file for each level
that has data.  The contour lines usually end up in at least one dig
file and the text usually ends up as a dig file (a box is drawn around
the text) and as a dig_att file (the value of the text becomes the
attribute of the box).  Then, you can use another GRASS program called
"v.cadlabel" to attach the dig_att values of the text to the contour
lines.  Sort of automates labeling, although you usually have to do
some hand labeling in "v.digit" as well.  I know that this sounds
complex, but if you try it and see the results on the screen, it makes
sense.  

Unfortunately, this doesn't exactly solve your problem, but maybe it
will clarify the issue.

Melissa