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[Malcolm Williamson]

> 
>  Hello GRASS-users,
> 
> I want to utilize the routine v.to.rast ( with v.support ), but
> I digitized the vector data sets as dxf format of Autocad.
> Now, v.in.dxf works well, into dlg format.
> v.support and v.to.rast are working, but dig_plus and dig_att
> files concerned are not generated. Therefore, just blanks in d.mon and d.rast.
> According to GRASS manual, it is shown that v.digit with digitizer connected 
> with GRASS is needed to do that. Is that only way to v.to.rast ?
> Therefore, my problem is
> v.to.rast without v.digit... How ?
> Anyone help me .
> Thanks in advances.
>                                                   K. Lee
> kilee at ccu.umanitoba.ca
> 

As you probably realize, v.to.rast requires vector polygons to be labeled to
become raster areas (this is where the raster map draws its category values
from!). Meanwhile, you cannot import attribute values with dxf file format -
this is why this is not a good import format to use! However, from Autocad,
I don't believe that you really have any other choices.

The solution, therefor, is to label the vector polygons, either in v.digit
using <none> as the digitizer and using your mouse as a digitizing puck, or
using the command v.alabel, which enables you to bulk label vector polygons
(GRASS4.1 alpha command). If it doesn't matter what the value of the polygon
attributes are, I'd go the v.alabel route. Otherwise, you're stuck digitizing.

Don't forget to run v.support again after labeling your vector files!

Good luck,
-- 
Malcolm D. Williamson - GIS Specialist           E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
Ozark Rm. 12                                        Fax: (501) 575-3846 
University of Arkansas              
Fayetteville, AR 72701