[GRASSLIST:1421] Re: REPOST: d.vect cutting algorithm?

Johansen Per Henrik per.henrik.johansen at norgit.no
Mon Feb 5 06:55:27 EST 2001

Both layers continue to the west (I am using the spearfish mapset and that
should be correct, or? You should also be able to reproduce this effect).

I also tried a little experiment and rezised the X display; this also seem
to cut the roads to the west! See http://www3.norgit.no/apnee/tcl2.png

I have no idea what is happening, but it seems to that d.area and d.vect
uses different cutting functions or are invoked with different coordinates.
I have tried to look in the source, and I see that d.vect has a plot2()
function that is missing from d.area. Might this have something to do with
my problem? 

FYI: There is no more map data to the east, thats way it is not cut off, I
have tried this with some of my own mapsets and GRASS happily cuts to both
east and west, but never to the north and south.

FYI2: I am using Grass 5.0 beta 10

Per Henrik

Per Henrik Johansen
Norgit AS, http://www.norgit.no 

-----Original Message-----
From: Eric G . Miller [mailto:egm2 at jps.net]
Sent: Saturday, February 03, 2001 3:25 AM
To: 'GRASSLIST at baylor.edu'
Subject: [GRASSLIST:1417] Re: REPOST: d.vect cutting algorithm?

On Fri, Feb 02, 2001 at 10:00:40AM +0100, Johansen Per Henrik wrote:
> Grasslist, 
> I tried to send this request some days ago but it seems that it never
> reached the list. I apologize if this request should reach you twice.
> I am having some difficulties when trying to join several vector layers
> a raster file; GRASS will not draw vectors (polygons work fine) at the n
> leftmost and/or n rightmost pixels of the image. 
> I use the d.area command to draw polygons and d.vect to draw lines. d.vect
> seems to cut off lines that stretches beyond the edge of the image. Is
> a known problem or am I missing out on something?
> An image that illustrate my point (roads and streams near the left edge is
> cut off) might be found at:
> http://www3.norgit.no/apnee/D_cell.png
> It is generated with the following GRASS commands:
>    g.region n=4928226 s=4911624 e=612344 w=593807
>    d.mon start=CELL
>    d.mon select=CELL
>    d.area map=fields fillcolor=green linecolor=black
>    d.vect map=roads color=red
>    d.vect map=streams color=blue
>    d.mon stop=CELL
>    g.region raster=D_cell
>    r.out.png D_cell
> I have also tried to use tcl/tk interface to generate the same image/map.
> Here everything seems to work fine, see
> Anyone know what I am experiencing here?

You sure your vector layers (other than fields) continue to the west?
The D_cell version obviously contains more real estate on the west side
than the X monitor version.  The X monitor version draws the roads about
to where they "cut off" in the D_cell version.  So maybe the CELL driver
is drawing more than you want?

Eric G. Miller <egm2 at jps.net>

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