[GRASSLIST:6344] Re: convert vector to raster

Maciek Sieczka werchowyna at epf.pl
Wed Apr 6 04:13:28 EDT 2005


I've got a question regarding the opposite situation. When I convert a 
colorfull integer raster (eg. landuse) to vector polygons, how can I 
preserve colors in the resulting polygon vector layer, ie. copy raster's RGB 
values to output's datatable GRASSRGB column?

Also, is it possible to assign colors to vector layer automaticaly in a 
similar way that  r.colors does it for rasters? It's important for ps.map. 
So far I've been converting my polygon vectors to raster, r.colors, and 
ps.map then. How could I specify a colortable directly on a vector layer?


----- Original Message ----- 
From: "Michael Barton" <michael.barton at asu.edu>
To: "Carlos Henrique Grohmann" <guano at usp.br>; "GRASS mailing list" 
<GRASSLIST at baylor.edu>
Sent: Wednesday, April 06, 2005 7:24 AM
Subject: [GRASSLIST:6343] Re: convert vector to raster

> Carlos,
> You are almost there. Use the 'rules' option in r.colors to specify the
> color you want for each value in your new raster map. Then you can do the
> drape with the colors you want. For an ortho-view, create a shaded relief
> map (under raster/terrain analysis in the menus). Then drape the colored
> geology raster over it using d.his (display/display raster map in the
> menus).
> Michael
> On 4/5/05 2:29 PM, "Carlos Henrique Grohmann" <guano at usp.br> wrote:
>> Dears,
>> I was trying to make a 3D dysplay of a DEM with geology over it, but NVIZ
>> doesn't handle vector areas (color filed), so I figured out about convert 
>> my
>> vector geology to raster, but then I couldn't get the colors! I can set 
>> up a
>> single value, or a column in the table, but this col can't be GRASSRGB, 
>> which
>> I
>> use to give me the right colors on screen.
>> How can I get this 3D-geology?
>> thanks all
>> Carlos
> -- 
> Michael Barton, Professor
> School of Human Origins, Cultures, & Society
> Arizona State University
> Tempe, AZ  85287
> Web - http://www.public.asu.edu/~cmbarton

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