[GRASSLIST:1181] Re[2]: ps.map pixel size and line attributes

Roger S. Miller rgrmill at rt66.com
Fri Nov 24 23:59:34 EST 2000

On Fri, 24 Nov 2000, Eric G . Miller wrote:
> I'm not sure, but I think that width maybe should be "points" rather
> than pixels.  If that's the case, 1 point = 1/72 inch (according to
> Adobe).  But I don't know for sure.  I don't know what "pixels" would be
> in reference to.

I rechecked the man page and it definitely says pixels.  I took that as
being a line width (literally correct only for vertical and horizontal
lines) in terms of the postscript device resolution specified in the
ps.devices directory and selected with "ps.select".  If the document
should say "points" then that might explain the behavior.
> Well, did you try running v.support on the file before doing the bulk
> labelling.  I think it needs that to work (though it should produce an
> error when it can't perform the operation).

I did run v.support.
> Anyway, the line labels are identified by two files.  The first:
> dig_att/<map> holds a series of entries identified as 'P' for points,
> 'L' for lines and 'A' for areas.  Each entry is then followed by an
> easting, northing and a category value.  The coordinates of the entry
> should fall on the degenerate line for a point, the line for lines, or
> within the area (but outside of islands) for areas.

Thanks a lot, Eric.  That should be the info I need.  I've been waiting to
download the programmer's manual until I have a little more time on my
hands to study it.  If it contains this sort of information then I should
probably read it before I bother the list much more.

Roger Miller

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