Help on ps.map ?

Hi !

do you can help us ?

We have following problem with the ps.map output. The background raster map
is a city plan of Frankfurt / Germany (scanned with 300 dpi resolution).
In ps.select we use a effective resolution of 400 (dpi ?) and a papersize
equal to the size of the scanned map. In g.region we select the whole area
of the raster map (8000 columns x 10000 rows).

As first try, we want to have a 1:1 copy on our postscript printer (300 dpi
resolution). To our really surprise we can hardly read the city names. It
seems to be that only every third pixel will be printed and an advise for
this obvious behaviour is the file size of the ps output.
If we zoom in the region, the output quality will be better. Off course,
all other parameters are the same, no scaling and so, but the rows and
columns changes, depending on the choosen region.

The resolution for the ps-output sems to depended on the number of the columns.
For example: columns=800 good quality, columns=2000 medium quality,
col=8000 bad quality. (Quality is : how good we can read the street names)

Maybe the programm looks for the number of columns and scales down
from given levels on ?

Do you have an idea what happen's ??

Many thanks !!

bye Jens and Alex

--
work : currently not available
home : jens@zaphood.tng.oche.de Jens Bitter, Beeckstr. 9
PR : DB4KH@DK0MWX 52062 Aachen, Germany

Please look for my new sub.domain tng.oche.de !!!
## CrossPoint v3.02 ##

I believe that this problem was fixed in Update 4 (GRASS 4.1.4). The
following is a quote from the UPDATES.5 file:
-------
  3. increased the maximum number of pixels allowed on a page in
function
      map_setup.c :
          limit = 300000000L;
     if the total number of pixels is larger than "limit" then ps.map
     reduces it to limit
     This change allows us to print layers at their actual resolution.
     For example: an AVHRR layer at 151 cells per inch.

     NOTE: we are thinking about assigning different upper limits to
different
     Postscript devices, as an additional parameter in the ps.devices
files.

(lines deleted)
STATUS:
    FIXED with update package 4
---------

On 20 May 1995, Jens Bitter
wrote:

Hi !

do you can help us ?

We have following problem with the ps.map output. The background raster map
is a city plan of Frankfurt / Germany (scanned with 300 dpi resolution).
In ps.select we use a effective resolution of 400 (dpi ?) and a papersize
equal to the size of the scanned map. In g.region we select the whole area
of the raster map (8000 columns x 10000 rows).

As first try, we want to have a 1:1 copy on our postscript printer (300 dpi
resolution). To our really surprise we can hardly read the city names. It
seems to be that only every third pixel will be printed and an advise for
this obvious behaviour is the file size of the ps output.
If we zoom in the region, the output quality will be better. Off course,
all other parameters are the same, no scaling and so, but the rows and
columns changes, depending on the choosen region.

The resolution for the ps-output sems to depended on the number of the column

s.

For example: columns=800 good quality, columns=2000 medium quality,
col=8000 bad quality. (Quality is : how good we can read the street names)

Maybe the programm looks for the number of columns and scales down
from given levels on ?

Do you have an idea what happen's ??

Many thanks !!

bye Jens and Alex

--
work : currently not available
home : jens@zaphood.tng.oche.de Jens Bitter, Beeckstr. 9
PR : DB4KH@DK0MWX 52062 Aachen, Germany

Please look for my new sub.domain tng.oche.de !!!
## CrossPoint v3.02 ##